Guest Author, Katie Arnolds, is a student in the PhD program at the University of Colorado Anschutz Medical Campus
We grow up thinking of taste as one of the five senses, but taste is so much more! Taste is the result of all the senses working together. While we eat, our brains process information from our taste buds, visual cues, sounds, smell, and touch. Taste buds tell us if something is salty, sweet, sour, bitter, or umami (savory), all of which essentially let us know if something is palatable. Extremely bitter or sour foods could be a warning that food may be poisonous or rotten. We respond positively to sweet and salty foods because they contain necessary electrolytes and carbohydrates and savory foods provide essential amino acids. If we eat something that provides what our body needs, the brain releases dopamine thus eliciting pleasure and encouraging you to repeat that action. This is a reward pathway in the brain.
We all know there is more to flavor than just salty or sweet; the complexity starts with the nose. As we eat, air from our mouth goes to olfactory receptors in the nose. The brain then combines these signals with information coming from the taste buds such as flavor and texture. Our eyes and ears shape the experience as well. Adding red dye to white wine can trick even experienced wine tasters into thinking they are drinking red wine. Also, consumers will report that a cheese that has sharp edges tastes “sharper” than the same cheese that is cut round. Being able to hear the crunch of your potato chips influences how crispy you think they are. The brain puts all this sensory information together and then incorporates personal biases and perception, which recent research indicates may play a large role in how we experience our food.
It’s always a treat to go out for a nice meal, but is it possible that our perception of the quality is proportionately influenced by the size of the bill? It seems that simply the suggestion that we are getting better food can change our perception. Researchers at Cornell University observed that participants rated food they believed was more expensive as tasting better. Interestingly, people who were told the same food was cheaper not only rated it as less flavorful, but were also more likely to report feeling full or guilty they’d overeaten. Another study investigated how the perceived cost of wine would influence consumers’ experience. People were given the same wine, but were told that it either cost $10 or $90. Those who received the”$90” bottle rated the wine much higher than those who received the “$10” bottle. This study also used a functional MRI (fMRI), a machine that measures brain activity while a person is engaged in an action. fMRI images of the people who thought they were drinking the expensive wine showed increased activity in the region of the brain associated with pleasure.
Understanding this complex phenomenon may be exploited to sell us junk food and get us “hooked” on certain products, but it could also enable us to enjoy our food more and avoid overeating. For instance, another study found that diners who ate their meals under dim lighting enjoyed their meals more and consumed less, than people eating the same meal under bright lights.
We all know food activates the reward center of the brain, but it’s becoming clear that the pleasure we derive from eating is the result of many factors. So for your next meal, embrace the experience and enjoy!
(This is an edited version of an article that originally appeared in the Spanish Language magazine, Contrapoder, co-edited by the Denver Museum of Nature & Science and the University of Colorado Anschutz Medical Campus for the monthly blog series, “Know Health”. Reposted with author’s permission.)
The celebration of Halloween has long been paired with spooky costumes and devilish amounts of candy. But just how much sugar does the average American child eat on Halloween? According to Insider it’s nearly 384 grams, which translates to about 3 cups of sugar. The average American consumes roughly 22.7 teaspoons of sugar each day. That is a third of the Halloween average, but on a daily basis. Why is it that we consume so much? One would think we eat this much candy because it’s Halloween and that’s what you do, but science says that is only part of the reason.
First, and most significantly, our love for sugar is because of survival. When we eat sugar, the interaction between sugar and the brain happens almost instantly.
This makes sense. Because before the advent of convenience stores, supermarkets, and candy shops, carbohydrates (including sugar) were hard to come by. Sugar is a carb that provides our body with pure energy, so naturally, our bodies evolved to make it pleasurable to consume. There are several commons types of sugar found in our everyday foods such as: sucrose, or table sugar; fructose, which makes up half of a table sugar molecule; lactose, found in milk; and glucose, the other half of the table sugar molecule.
Fructose is found in fruit, which brings us to the reason our brains are wired to crave it. Rich Cohen of National Geographic, through his interview with Richard Johnson, a nephrologist at the University of Colorado Denver, discovered details about our ancestors’ fructose deprived past. To paraphrase, Cohen reminds us of the present theory of humankind’s emergence from Africa, some 22 million years ago, and their great exposure to fruit. Roughly 5 million years later and stretching for some time after that, there was an Ice Age which drastically reduced the abundance of fruit throughout our ancestors' habitats. The result of this reduction of fruit led to a mutation which was favorable in such an environment. “A craving for fructose would be just the thing our ancestors needed to survive,” said Cohen. Our ancestors began to process fructose quickly and efficiently, storing fructose as fat to brace for winter.
If our brain is programmed to like sugar, and it helps with survival, that means we will eat it again and continue searching for it.
This evolution of a pleasure mechanism for sweet foods took thousands upon thousands of years to develop, but our relatively recent advancements in civilization only took a few hundred years. Nature has never needed a pleasure “off-switch” related to sugar. We’ve always needed to seek sugar in order to create fat stores to survive winter.
In the 21st century, however, this drive does not serve us when we crave sugar while constantly being bombarded by opportunities to consume it. Especially since many foods contain high fructose corn syrup, which if eaten in high quantities, is broken down in your liver to produce fat.”
Though this hardwired mechanism for seeking sugar can be detrimental to our health, this is not to say that we should keep kids (and adults) from binging on candy for Halloween. The nostalgia, emotions, and culture that comes with Halloween will only strengthen sugar cravings anyway.
Instead, strive to cut out the excessive sugar amounts from your daily diet. Especially during the day on Halloween if you plan on slamming down 11 mini Snickers after dark. And if you eat a healthy breakfast and lunch, the candy at the end of the day won’t be the end of the world.
I received lots of passionate feedback about my article on pairing spicy food with IPAs (originally published by CraftBeer.com). In light of this “heated” debate between people who both love and hate spicy food, I thought a follow up on the science behind the sensation would help.
Spoiler alert: spicy is not a taste, it’s a mouthfeel. Just like the sense of touch on your skin, mouthfeel is the sense of touch in your mouth, and helps you detect pain, temperature, and textures. The key to detecting these sensations is your trigeminal nerve. To get a sense (see what I did there) of how this nerve works, let’s do a quick demonstration. Hold up three fingers on each hand with fingers pointing skyward, Girl Scout style so to speak. Now rotate them in to face one another and place them onto your cheeks with your pointer fingers laying on your temples, your middle fingers pointing to your nose, and your index fingers just below your lips (see picture above). You have effectively identified the location of your trigeminal (three branches, hence the prefix tri) nerve.
This baby packs a punch. This is the nerve that dentists numb up before drilling, that tells you you’ve bit your tongue, and that makes you cry when you are cutting onions. And yes, this is the nerve that signals to your brain that something is wrong when you eat something too spicy.
There are lots of teeny offshoots of the trigeminal nerve on your tongue and in your mouth, like live wires. When spicy food particles come along, like capsaicin from hot peppers, the capsaicin and the ends of the live wires (called receptors) connect and an electrical signal is sent to the brain.
That’s when things get interesting. You’ve probably experienced these symptoms when eating spicy food: sweating, runny nose, eyes watering, face gets hot and red. This is a classic response to pain, and just like on your skin, it happens in response to spicy food in your mouth.
In order to handle the pain, first we typically reach for something cold. That's because the same receptor for spicy also helps us detect heat. So our brains think, “Fight! Fight with cold!” And grabbing that chilled beer or ice cold water helps… but only temporarily. That’s because cold doesn’t break the connections between the capsaicin and the receptor. All it does is turn on a counter receptor for cold and the brain for a moment is tricked into thinking all is well. But as soon as the cold dissipates, the mouth is right back to feeling on fire.
Because spicy is a mouthfeel, not a taste, you need to combat it using mouthfeel techniques. In order to feel relief, you need to pull the capsaicin off the receptor. To do this, we need to understand a little bit about chemistry. Capsaicin is hydrophobic. For lack of a better analogy this means capsaicin is scared (phobic) of water (hydro). In terms of chemistry, this means that water will not attract the capsaicin away from the receptor. Which means that cold water and cold beer (which is mostly water), doesn’t do the job. You need something that has fat or oil in it, something that will woo the capsaicin away from that trigeminal receptor.
With that in mind, think about some of the culinary pairings across the world, thai coffee prepared with condensed milk to pair with thai hot curry, cucumber raita with Indian vindaloo, blue cheese dressing with buffalo wings. These notoriously hot dishes all traditionally served with something dairy based to offset the heat. In addition, the more spicy food you eat, the more you desensitize the nerve. Even from the womb, babies start learning tolerance to hot food if their mother constantly eats spicy food while pregnant. So in addition to techniques for dealing with a spicy emergency, you can also just eat something spicy every day to build your tolerance.
Then again, you might just love the burn. In which case you have mouthfeel and your trigeminal nerve to thank.
My career cultivating a scientific understanding about flavor has prepared me for contributing to beer knowledge, but not “growing up” in the industry means that I often am not aware of the many shared stories, anecdotes and oral histories that have been passed down from one brewing generation to the next. So it’s not surprising that I find myself stumbling into these moments of tension where my grasp on the science behind a phenomenon, like beer calming spice, doesn’t quite match up with the brewing industry’s perspective.
Along those lines, I recently got myself in a bit of boiling water. I was presenting a workshop of food and beer pairing alongside my colleagues on the Beer & Food Working Group, when I made a comment about the dated image of beer and hot wings and made the mistake of following that up by saying beer is a pretty terrible choice for spicy food. There was an audible gasp in the audience, and I looked over to find my friend, and incidentally, publisher of CraftBeer.com, Julia Herz shaking her head with eyes wide. I learned later that for many craft connoisseurs like Julia, beer is a go-to for spicy Thai and Indian food. She swore that it was the residual sugar in the beer that made the pairing work.
The initial wave of relief you get from the beer is the same as you would get with any cold beverage. It temporarily cools your mouth, but as your mouth warms back up, so too does the burning sensation.
To solve this puzzle, we need to consider all the players.
How Your Taste Receptors React to Spicy Foods
First, the reason why spicy foods cause a burning feeling is because they contain an irritant. For this reason, spicy is a mouthfeel, not a taste. It could be capsaicin in chili peppers, gingerol in ginger, or cinnamaldehyde in cinnamon to name a few. These irritants bind to receptors on the tongue, which kicks off a chain reaction and signals to the brain that there is something potentially dangerous in the mouth. This causes the brain to unleash a typical pain reaction: dilation of blood vessels cause your skin to get red, sweating occurs, and you actually feel like your mouth is burning. The goal of a pain reaction? Your body is telling you to counteract. If you’re reading this post, my guess is that you counteract by picking up your beer.
The initial wave of relief you get from the beer is the same as you would get with any cold beverage. It temporarily cools your mouth, but as your mouth warms back up, so too does the burning sensation. Temperature is only a temporary fix because the capsaicin is still tightly bound to those receptors and they are still sending signals to your brain that all is not well. You need something that will pull that irritating molecule off your receptor and wash it away.
And that leads us to learn a bit more about capsaicin. Capsaicin is hydrophobic. This literally means it hates or is fearful of water, and chemically it means it won’t dissolve in water-based solutions. It is, however, drawn to high levels of fat like whole milk, or something high in ethanol even, releasing the pain receptors on your tongue from its grasp. Beer has alcohol, and some beer styles have higher ABVs, so beer might work you say!
Why Alcohol and Spice Don’t Always Play Nice
But alcohol is a double-edged sword when it comes to spicy foods. First, it too is an irritant and activates those same pain receptors that capsaicin does. So in a way, it might actually make the problem worse. It will send more signals to the brain that you are in trouble, causing a stronger pain reaction. However, at a high enough ABV, capsaicin could dissolve into the ethanol, pulling it away from your receptors. The problem with beer, even the biggest baddest beer you can find, is that it has more water content than alcohol. Therefore, it will do you little good to sop up the spice and stop the burn.
There are a few other factors that make beer a tricky mate for spicy. One is effervescence, which is the amount of gas dissolved in beer. Carbonation is shown to activate pain receptors at certain concentrations. The second is bitterness. Going against almost all the conventional wisdom I gleaned from beer bloggers and discussion logs, I contend bitter is not a friend when it comes to spicy. In a particularly entertaining, though out-dated discussion on Beeradvocate, almost all the folks that chimed in gave the craft beer party line that a hoppy IPA was the go-to for spicy food. Only one brave soul (hey GCurlow!), went against the tide and noted the combo caused an increased perception of heat, bitter and alcohol. The science supports the lone divergent voice. High alpha acid content matched to high capsaicin do actually amplify each other, making the bitter more bitter and the spicy more spicy, and the burn of alcohol more potent, potentially making the whole package intolerable. GCurlow ended with a comment about pairing with a beer of high sugar content equivalent to riesling.
So like Julia preached, the last piece of the puzzle to calming spice may be sugar. In the case of beer we are honing in with a laser-like focus on residual sugar. If you scour the internet, you will find a number of blog posts telling you just how to kill the burn of chili peppers, and as far as I read, they all included sugar as a possible solution — either straight sugar, or sugar in the form of a doughy gluten-laden bakery bomb. I didn’t find much connected to beer until a blog post from Sam Adams jumped out at me. In honor of IPA Day, they ran a small panel of tasters alongside chefs from the Culinary Institute of America in which they described the intensity of medium-hot chicken wings when paired with three variations of a west coast IPA.
Can an IPA Calm Spicy Chicken Wings?
Everyone has great experiences that we can test scientifically. The gang at Sam Adams ran a small but definitely fun experiment on spicy chicken wings and IPA. Although the results they share wouldn’t hold up to scientific peer-review and should not be considered scientific fact, they do give us a glimpse into what might be going on and how we might test this in a controlled setting with data from a large group of participants.
Right out of the gate, I loved that the first observation of the panelists at Sam Adams matches beautifully with what sensory scientists have shown: the highest ABV beer (8.4%) led to increased sensation of heat. However, it’s confounding that the mid-level ABV (6.5%) decreased the heat where the lowest ABV option (4.5%) made the heat linger. The IBUs could also be at play then. In terms of bitter being known to amplify the perception of spicy, the 8.4% beer came with a whopping 85 IBUs which might have contributed to the increased heat. The other two beers both rounded out at 45, so the IBUs in this case don’t help us understand why the heat sensation was so markedly different between the 6.5% and the 4.5% ABV beers.
Again, we are left to contemplate sugar. The panelists at Sam Adams didn’t come out and say residual sugar, but they did mention that the higher the malt characteristic of the 6.5% ABV choice seems to balance the heat perception and that it was this malt characteristic that also brought a sweet perception to the pairing. As far as the scientific research goes, I was unable to locate any reference to sugar being an antagonist to receptors for spicy, nor could I locate anything that says it isn’t. In short, there is no scientific evidence that I could find that says sweet calms spicy, but perhaps the study just hasn’t been conducted yet.
Bottom line, IPAs with their big ABVs and even bigger IBUs probably aren’t what you want to help with the burn of your favorite spicy food. But that doesn’t mean you won’t still reach for it. That’s because your personal preference — how much you like something — is different from perception (how much you detect something). My guess is that you may have conditioned yourself to love the pairing due to years of use, making it familiar and safe. And even though that IPA really isn’t helping the burn, as a human being you are a creature of habit. This is supported by science: we love what is familiar. It is for that reason alone that you may find IPAs and spicy food a pairing that you can’t live without, and not because it calms the burn.
The stories coming from brewers and chefs, who are some of the most mindful consumers in the world, make for some of the best scientific hypotheses in sensory. This is one of the reasons I love consulting in beer. These are questions that should undergo a rigorous scientific look so that we can move both the science and the industry forward. The gang at Sam Adams ran a small non-scientific, but impactful test using spicy chicken wings and IPA, and by doing so inadvertently shed a bit of light on the possible role of residual sugar in spicy pairings. Light that scientists should consider in selecting and designing the next generation of sensory studies.
Here’s your invitation to contribute your experience. Share your beer flavor question or anecdote that you think could use some science backing in the comments section. It could be the topic of my next article or even end up as the basis for our next scientific study.
We had three goals for prototyping the Crowdtasting: The Science of Beer & Food Pairingsresearch event we hosted on March 25, 2016. 1) We wished to understand what the logistics of ethically engaging 400 people into a flavor study at the Museum would look like when done efficiently and effectively. 2) We needed to establish if crowdtasting research events attract people that will take the research seriously and provide high quality data. 3) We wanted to learn how to better design the recipes, select the beers and ask the questions of a crowdtasting audience to ensure that the results would withstand peer-reviewed scientific publication.
(Information on the Beer & Food Working Group can be found here)
Disclaimer: This report is not peer-reviewed and represents a rudimentary analysis of the data for public sharing. The data will be more rigorously analyzed and then used to formulate hypotheses for future research studies (both crowdtasting and in the Genetics of Taste Lab). The results of future studies will be submitted for peer-reviewed scientific publication. In addition, for those of you that joined us on March 25, 2016, we shared with you the quick and dirty data. That was not a statistical analysis, but rather a visualization of where each food was rated individually (scored by the scale choice with the most responses) compared to the same food with each beer. Therefore, the statistical analysis you see here may disagree with that presentation, and in such cases the results presented here is a more accurate representation of the data. Finally, logistics prevented randomization of the beer and food order for this event. This is something we will strive to accomplish in future studies.
Results for Goals 1 & 2
1. Logistics: We still have much to assess (and we have plenty of meetings scheduled just to work through this very item!), but in short the logistics were a challenge meant to be overcome. Even between the first and second sensory sessions we learned so much about what to have ready (e.g. pitchers on the tables, paper surveys on hand when Wi-Fi and phones fail), what information to give verbally and what points on the digital data entry to reinforce, that the second session went far more smooth than the first. We currently have a survey request out to our 400 participants to learn more about how they felt the flow went, what was difficult, what they felt that we overlooked. We will take every bit of feedback into account as we determine how best to conduct crowdtasting research events in the future.
2. Crowdtasting Participants: Far and away the most impressive takeaway of the night was how poised, focused and dedicated our public panelists were. As I analyze the data, I continue to be impressed with the aptitude of the audience we hosted. We know now that we can ask much more in-depth questions, including intensity scaling of this group, which will allow us to ask higher impact questions in crowdtasting research events moving forward. A huge kudos to all of you out there that attended and contributed such high quality data!
Results for Goal 3: To come! But here is some info on the demographics of the particpants
Gender. Using a two-sample t-test, we found that men and women show statistically different (p-value < 0.05) preference ratings for one food item (men preferred the pepper sauce) and two of the beers (men preferred the stout and the IPA) (Table 1). It is also note-worthy to mention here how much women in Colorado rock. My colleagues in the beer industry were impressed with the fact that a craft beer event attracted more women than men (Figure 2). This is opposite of the typical trend, and as a scientist and craft beer fan that happens to be a woman, I was in good company last Friday night!
Table 1. Comparison of preference scores of both the beers and the food items of men and women. (*indicates the gender difference in preference for that item statistically significant)
Savory Tart 1.000
Pecan Shortbread 0.869
Pepper Sauce 0.000*
Beer A (Brown) 1.000
Beer B (Hefeweizen) 1.000
Beer C (Stout) 0.000*
Beer D (IPA) 0.001*
The origins of the Beer & Food Working Group
Spurred by both the growing interest in and the inconsistent language of beer and food pairings, Julia Herz of the Brewer’s Association started gathering input from industry leaders and sensory scientists alike. In 2015, her informal scan led to the formalization of the Beer & Food Working Group.
The Beer and Food Working Group aims to be the trusted beer and food pairing resource by collecting, creating and communicating a sound and scientific understanding behind the common joys of eating and drinking. We want to make beer the model for other beverages in terms of the way we understand, discuss and do beer and food pairings, pushing the thinking into new territory.
We are making progress everyday! You can follow the results of our work by attending our presentations and workshops at the annual Craft Brewers Conference, the World Brewing Congress, or by visitng us online through this blog and via #BeerFWG on social media.
Our Values & Intentions
Use scientific research-backed references and resources
Respect personal preference
Recognize the value of anecdotes as possible hypotheses and value the community's knowledge base as a tool for education and further research
Encourage creativity in expression and retain as rich and evocative a language as possible
Advocate the philosophy that successful pairings come at the intersection of art and science
Acknowledge the validity of different approaches and be inclusive in bringing together theory, practice and experience of all those engaged in food and beer work
Collecting: We will continuously clarify and classify the evolving pairing vocabulary and vet it against existing scientific literature to standardize the terminology of pairing. We will monitor and assimilate data from future sensory studies of flavor interactions as they relate to beer and food pairing.
Creating: We will take the lead in determining useful consumer preferences and tendencies, encourage wide ranging research related to this topic, and engage the brewing community to further research on pairing.
Communicating: This group aims to generate and advocate for a research-backed framework to serve as the consensus standard within the beer and food industry worldwide.
Members of the Beer & Food Working Group
Julia Herz, Founder
Craft Beer Program Director for the Brewers Association, and co-author of Beer Pairing (Voyageur Press) and the CraftBeer.com Beer & Food Course
Ray Daniels, Founding Member
Founder and director of the Cicerone Certification Program, author of Designing Great Beers, and contributor to The Oxford Companion to Beer
Nicole Garneau PhD, Founding Member
Curator and Chair of the Health Sciences Department and director of the Genetics of Taste Lab for the Denver Museum of Nature & Science, co-author of the Beer Flavor Map
Randy Mosher, Founding Member
Author, Educator, Speaker, Creative Consultant for Beer
Pat Fahey, Member
Content Manager for the Cicerone Certification Program
Adam Dulye, Member
Executive Chef for the Brewers Association and CraftBeer.com, co-author of the CraftBeer.com Beer & Food Course, and culinary lead for SAVOR®: An American Craft Beer and Food Experience, the Farm to Table Pavilion at the Great American Beer Festival®, and the World Beer Cup®
It can be argued that crowdsourcing dates back to the early 1900s with the start of the Audubon Society’s Christmas Bird Count, now the longest running citizen science program. However, crowdsourcing was coined in 2006 by Jeff Howe of Wired magazine. He described it as the growing trend of everyday people using their spare time to “create content, solve problems, even do corporate R & D.” He said crowdsourcing represented “the act of a company or institution taking a function once performed by employees and outsourcing it to an undefined (and generally large) network of people in the form of an open call.” A decade later, none of us could have predicted how much crowdsourcing had changed the very way we do science.
Figure 1: The Bioscience Branch of Crowdsourcing’s Family Tree
To dial into the use of crowdsourcing for sensory science, let’s first consider the evolution of bioscience-based studies using this model. We turn back to 2005 when the Rosetta@homeproject was launched. A major obstacle in creating new drugs, cures and vaccines is figuring out the natural structure of biological proteins. Structure determines many things, including how that protein might bind and function in the body. To overcome this obstacle, scientists created a computer algorithm that would quickly test all possible structure to see which one would be most likely in nature (based on many variables, including thermodynamics). This is where crowdsourcing in bioscience first comes into play. The program could be downloaded by everyday people on their home computers. These users were essentially tapping their personal computers to contribute to a massive network dedicated to predicting these all important protein structures. This type of crowdsourcing is what I refer to as passive contribution to science (Figure 1) because as a user you're allowing access to something personally owned (in this case a computer, in more recent programs iPhones etc.) to generate data, but you yourself are not contributing data, nor are you contributing intellectually.
This original passive contribution through crowdsourcing led to the next stage in crowdsourcing bioscience, active contribution. Rosetta@home was designed to show the progress of the computer algorithm live to the home user through the screen saver on their computer. Literally, you could watch a rapid succession of possible structures cycle on your computer screen for a given protein. And in fact, people apparently did just sit there and watch and be mesmerized by bioscience research flashing before their eyes. That’s where it gets interesting. The human mind has incredible pattern matching and spatial reasoning, so the Rosetta designers started getting calls from people saying they had solved the problem far faster than the computer algorithm. What an extraordinary moment, to realize the potential value to science by the volunteered contributions of the masses.
From there, Rosetta evolved to FoldIt, a gaming interface that allows users to play and compete to solve protein structures. When truly successful, proteins designed through FoldIt have then been empirically tested in the lab. These players are taking crowdsourcing it to the level of intellectual contribution. This brings me to the scientific process and how I breakdown crowdsourcing into the two forms of active contribution: citizen science and self-data (Figure 2).
Figure 2: Crowdsourcing and the Scientific Process
While FoldIt is one of my favorite studies that allow users to contribute directly in the scientific process by data preparation, the American Gut project is my favorite example of self-data contribution. The American Gut team goes to great lengths to immerse users in the experience, from the way the data collection takes place to the quality of the shared information and comparative data. It is this audience focus that drives home the philosophical difference between crowdsourcing self-data contributions and regular old human subject research. Although close cousins and regulated as such (i.e., whether it's traditional human subject research or self-data contribution, if you want to publish, you need an institutional review process in place to ensure ethical protection of your contributors), self-data contribution is distinguished from its human subject counterpart by the resources placed in people as well as data. This is my rule of thumb for crowdsourcing: You should be as concerned about making the experience educational and enjoyable as you are about collecting data, and you will evaluate your study and elicit feedback from your contributors. This means you are really invested beyond just getting a data set. This takes time and planning alongside your research questions and instruments, and when done right includes proper evaluation to ensure you are meeting your educational and experiential goals.
To bring this home, at the Denver Museum of Nature & Science we use both forms of active contribution in crowdsourcing sensory data: self-data contribution and citizen science. In addition to the rule of thumb above, we follow a set of 5 rules to increase our chance of success (Figure 3). Using these rules, we currently have two models of crowdsourcing sensory science open to the public.
First, we have just embarked on conducting crowdtastings during events. Crowdtasting is a form of self-data contribution, and in this case, the self-data is sensory and involves some aspect of trying and rating a taste, mouthfeel, or aroma aspect for which flavor is known. This way we can generate data from a large group of people in just one session. This vastly improves the turnaround time from study design to execution to analysis and publication. By nature people self-select into this type of crowdtasting because of the entertainment value, and we also can better execute learning aspects for participants.
The second model of crowdtasting has been part of our portfolio since 2009. In our Genetics of Taste Lab, we found that a very special thing happens when you combine self-data and citizen science: You create personally relevant studies that are for the people, by the people. In this way, we crowdsource self-data from everyday Museum guests and the data is collected, processed, and in some cases even analyzed and communicated, by our citizen scientists. We conduct regular evaluation of our educational and experiential goals for both our Museum guests and our citizen scientists to ensure our working model supports both in addition to publishing papers on the results (Rule #5).
Figure 3: Six Steps to Successfully Design a Research Study Using a Crowdsourcing Model
Finally, speaking of Rule #5, I think this step is imperative. I’ve learned of projects where publication is not a goal. In these, the focus on providing a truly wonderful educational experience is the top goal. I would argue that if a project is not hypothesis-driven and publication (the gold standard for all forms of research) is not the goal, then it is misleading to tell users that they are contributing to real research. For this reason, I do not advocate collecting for collecting sake and building chock-full databases and data sets that are not used. Be true to your users, they are contributing self-data and their intellectual time and resources; they want to see their contributions make a difference. Do them a favor and design scientifically sound, hypothesis driven studies and publication is a no-brainer end goal. At the Museum, we don’t just talk the talk on this one; we walk the walk. Our scientific research has become the basis of a number of peer-reviewed scientific publications, including one co-authored by a citizen scientist. Moreover, as work conducted by the people for the people, we have provided free public access to all our lab-based studies (event-based studies are yet to be published). It is just one more step to thank people for the contributions they have made by participating in crowdsourcing in our lab.
I woke up at 3:35 am, cold sweats, difficulty breathing, stiff neck, and even had had a small amount of vomit, you know the kind that comes up and you swallow before you realize what just happened. My brain was racking itself for a logical reason for each. Was it because I had a deep tissue massage? That might explain the neck pain. Night sweats? They were more common immediately after I had my daughter. This was five months later, that couldn’t be it, could it?
The chest pain and difficulty breathing … maybe a panic attack? Was I stressed? Sure, but no more than normal, actually maybe even less; things were cruising along at home and at work. But wait, what about the day before? I couldn’t take in a full breath yesterday when I pulled out of the garage. I had chalked it up to the cold air and drove on my merry way.
In the end, I put forth every conceivable reason for what was occurring. Then and only then did I admit, yes at now 4:00 am, these are the symptoms of a heart attack in a woman. “I’m only 35,” I whispered in the dark of my living room. “This is crazy.”
Ultimately, if I didn’t have a family to think about and hadn’t scared myself silly with what-ifs, I wouldn’t have called Kaiser to talk to one of their docs. But, I was also afraid that I wouldn’t be taken seriously, so I actually didn’t call until after I nursed my daughter, got her ready, and got myself ready for work. Once I did dial the nurse number, they put me through to a doc and it was a big relief. First, small world, I knew the doctor already and he was incredibly compassionate as I detailed my story. I really was having the crazy symptoms that women experience during a heart attack. Although the chance was super slim that that it was due to a blood clot or a cardiac issue, the recommendation was to get checked out. So off to the ER I went, and against advice I have read online since, I drove myself. Come on, there was no way I was calling an ambulance!
But had things turned out differently, perhaps I should have. I had normal EKG, normal blood tests, and nothing crying out for attention on my chest x-ray. I was lucky. All the big bad stuff, like a blood clot or a blocked artery in the blood vessels feeding my heart that could cause a heart attack, were not there.
Had they been though, every minute could have counted. Unlike men, women can have symptoms over the course of days and even weeks-- slowly intensifying and persisting. And few of us out there acknowledge those symptoms and think heart attack. It just doesn’t look the same in women as it does for men. The GoRedforWomen.org website doesn’t mince words, “The longer a person goes without treatment, the greater the damage.” I later read that if you are reaching for an aspirin “just in case” then you should reach for the phone.
And that leaves us with some scary stats to consider. Heart disease is “the number 1 killer of women,” Go Red tells us, “it kills more women than all forms of cancer combined, and it kills more women than men. It’s often called the Silent Killer because heart disease victims often don’t even know they have it, so they don’t get treated or make healthy lifestyle changes.”
So join me in wearing red on Tuesday, February 5and check out the Go Red for Women Website (https://www.goredforwomen.org/home/about-heart-disease-in-women/)- seriously check it out! I know a lot of about human health (it’s my job) and yet I still found myself sitting back dumbfounded, thinking, “I didn’t know that,” and multiple times uttered, “Huh,” as I stumbled upon something I hadn’t considered before. And if you can, donate to the cause.
As for me, I still don’t know why I can’t get a deep breathe in (chest congestion due to a cold is my current theory), but I’m now up to snuff when it comes to heart disease prevention in women, and I’ll proudly wear red on Friday, February 5 to help others too.
The Genetics of Taste Lab was host to the fatty acid taste study from November 2014 to August 2015. In that time we enrolled 1020 Museum guests, ages 8-90, as part of the crowdsourced data collection. The study was a true success in both citizen science and crowdsourcing, AND now that the data have been analyzed, we can share that it is a scientific success as well!
Scientists have long accepted that sweet, sour, salty and bitter are basic tastes. More recently, umami (savory) was added to the list. And now through the findings of our study as well as those of our collaborators, we can finally prove that there is a sixth taste: fat, or as it is starting to be known in the land of taste, oleogustus.
There is a thirty year history towards proving that fat is the 6th taste, however the final nail in the coffin came this year when our collaborator, Dr. Richard Mattes of Purdue, and his team published their research "Oleogustus: The Unique Taste of Fat." This finally put fat taste on the map. Now that we know people can detect the taste of fatty acids, we need to figure out how it happens and what it means for human health. That’s where the Genetics of Taste Lab’s work comes in. Using an omega-6 essential fatty acid (linoleic acid), the Lab examined both genetic and environmental factors that contribute to the ability to taste this important nutrient, and the role it has in obesity.
The first published results of the study, No Difference in Perceived Intensity of Linoleic Acid in the Oral Cavity between Obese and Nonobese Individuals, appears in the October 2015 issue of the leading journal Chemical Senses, published by Oxford University Press (free open access!).
The study had dual purposes. The first was to determine whether people can, in fact, discern the presence of linoleic acid. In a survey of 735 subjects, ranging in age from 8 to 90, of white, black, Asian and Latino ethnicity, the answer was definitively yes, people can detect the taste — but to different degrees.
The second was if taste acuity plays a role in obesity. In answer to this question, the researchers found no link between %BF and ability to perceive the taste of the linoleic acid. “We didn’t find that %BF would predict someone’s sensitivity to fat,” our partner and lead author, Robin Tucker-Falconer, RD PhD said. “Now we know we need to explore other areas, like genetics or dietary exposure, for those results.” We are now in the final stages of the genetic analysis, with the goal of finding the gene responsible for fat taste- stay tuned!
The results also revealed an interesting pattern in sensitivity. Women were much better than men at discerning the taste, and young people 17 and under, especially girls, were better than older people. “This was one of the first studies to look at how kids experience fat taste,” Tucker-Falconer said.
What was unusual about the study — and what enabled it to include such a large and diverse set of subjects — was that it was conducted with the help of citizen scientist volunteers that crowdsourced over 1000 Museum guests as human subjects in the Genetics of Taste Laboratory housed within the Museum. Our research partner, Tucker-Falconer adapted the research methods she had used as a graduate student at Purdue, where she tested about 100 participants over four years, to the museum setting, working with our team to design the study and to train the volunteers.
The proof is now I the pudding. “This was far and away the largest sampling that has been done,” said Mattes, a longtime researcher into the biology of taste. “Working with the citizen- scientists is a wonderful scenario,” Mattes continued. “With their interest and willingness to be trained and their commitment, it’s just a perfect situation. It enables us to study large populations in an efficient way.”
This two-year study was led by Nicole Garneau PhD (email@example.com) and Richard Mattes PhD (firstname.lastname@example.org), and made possible by a partnership between the Health Science and Visitor Programs Departments at the Denver Museum of Nature & Science and the Nutrition Science Department at Purdue University.
So many of you crafty beer and savvy food folks who follow the Genetics of Taste Lab know how beery nerd beery I can get when it comes to the creativity of our local culinary geniuses and brew masters. So it should come as no surprise how uber-jazzed I am to have been invited to co-host the class, Science, Craft Beer & Chocolate Desserts with Chef Sarah Amorese(owner and chocolatier of Boulder’s Piece, Love & Chocolate), Jeff “Mendy” Mendel of Longmont’s Left Hand Brewing Company, and the Museum’s own, Chef Patrick Harnett.
Intrigued? Here’s the scoop. The class will be held on Wednesday, December 10 from 7-9pm, and includes a flight of 8 beers – all from local Colorado craft breweries – and a pairing of more than 10 different chocolates & chocolate micro-desserts.
Now here’s the behind the scene scoop. Mendy, Chef Harnett, and I will have the tedious task on November 18 of visiting some of our favorite Denver bier haunts to select our 8 picks for the pairing; you’ll have to keep a keen eye on Twitter as we release the names of the top flavor picks! I'll be using #beerchoco to announce our picks.
We’ll send our top beers and flavor profiles to Chef Sarah, who will work on designing micro-desserts that we will then pair with the selected beers. We’ll then do a final tasting to ensure the pairings hit all the class notes (science and sensory) that we want participants to experience. In this way we will pull together the worlds of science and art to create a series of tastings that (we hope!) will blow your mind.
The experience itself comes wrapped up in the bow of expertise that my co-hosts and I bring to the table. You will walk away with everything from history, to neuroscience, to culinary insider’s knowledge, to well-meaning foodie banter to use for fodder at your next happy hour.
We were there to fulfill my end of the Brewer for a Day end of a bet from last year, but truly it was about brewing a collaborative Maya-inspired beer for the Museum’s annual Science on Tap event. Patrick Crawford, cofounder of the Denver Beer Co., had already fulfilled his end of the deal, joining the ranks of Michele and me as a Curator for a Day, so it was the scientists’ turn to take on the role of brew master.
It was already sweltering by the time we arrived at 10 a.m. at the brewery on Platte Street. I had ridden my bike, and the commute left me yearning for cool air conditioning and a frosty brew. But I got neither. Breweries are not the coolest of places (temperature, of course), and Patrick reminded us that there was work to be done if we were going to get this beer brewed.
First item on the docket was prepping our first ingredients for the mash: barley, corn, and sweet potatoes. Patrick used a keg to boil the sweet potatoes earlier that morning and gave us the task of turning it to mush. At first, we began cutting the keg-roasted potatoes into chunks, but being the scientists that we are (brains before brawn my friends!), we improvised and created a new, more-efficient mushing method. We dumped the 60 pounds of sweet potatoes into a 50-gallon barrel. Michele spied the metal paddle used to stir the mash and repurposed it to crush the sweet potatoes. Concurrently, I put my guns to the test and lugged 55-pound bags of barley to the mill. Between the two of us it was quite the workout—and the triple digit temperatures didn’t help matters—but we were quickly rewarded with the luscious aroma of warm sweet potatoes and the sweet smell of freshly milled malted barley.
Next on the brew agenda: spice shopping. Charlie Berger, Patrick’s partner in crime and cofounder of the brewery, took Michele and me for a stroll down the block to see his spice guru, Matt Wallington, at the Savory Spice Shop. We were there to select chile peppers, a key ingredient used by the Maya. After very little debate, we all agreed on a quarter-pound of dried whole de arbol chiles, a hot pepper with an earthy aroma and just the right kick to complement the subtle flavors of our brew, including honey and roasted cacao nibs.
When we got back to the brewery, Patrick was working to transfer the liquor from the mash to the brew kettle for the boil. We selected a combo of fairly mild hops, again something to balance sweet but not overwhelm the flavor profile we are shooting for in this brew. We stopped for a lunch break during the boil, and afterward Michele earned her brewing stripes by cleaning out the mash tun. Everybody’s got to do it at least once! Later that afternoon we were joined by supporters of the Museum’s Young Professionals group to pitch the yeast and add in the final ingredients: chile peppers, cacao nibs, and honey.
It may seem like an unusual beer combination, but these ingredients, corn, honey, sweet potatoes, chilies, and cacao were selected after months of careful research. Earlier this year, we partnered with Metro State University to test ancient vessels that we believe held some kind of fermented beverage. We used a combination of techniques, including archaeochemistry—the chemical analysis of archaeological specimens—to examine the molecules that remain in ancient pottery from the Museum’s anthropology collections. Typically, archaeochemical techniques involve grinding the pottery specimen and then testing the powder for residue molecules. While effective, this is destructive and prevents future study of the object. Using sonication and gas chromatography, we set out to develop and test new noninvasive techniques that are just as successful at finding and identifying molecule residue. As part of this methodology testing, we found ourselves with a molecular “hit” from one of our samples, beeswax.
Comparative analysis with purchased beeswax showed an identical molecular signature. Sure enough, we had ourselves a discovery on our hands! While we are continuing to pursue method testing and following up on the beeswax lead, based on this scientific evidence, we selected honey to be the primary flavor for the beer experiment. From there, we researched other geographically and culturally accurate ingredients, including corn, chile peppers, chocolate, balché tree bark, agave, and flowers such as morning glories, to name a few. From these, we built a flavor profile to balance the sweetness of the honey, which is what lead to the corn, sweet potato, chocolate, and chile combination described above.
Not only is this brew project a unique way to bring science to life and join the past to the present, but the successful results of our noninvasive technique could help change some of the approaches used in the field of archaeochemistry, one ancient vessel at a time.
In the meantime, we invite you to be the first to try our beer! It is Batch 500 for Denver Beer Co., and thanks to our Young Professionals group and a long list of candidate names, the team ceremoniously named it the Tipsy Tzolk’in in honor of the Maya ritual calendar. It will be served at Science on Tap on July 21 at Denver Beer Co and during Summer Nights @ the Museum on Friday, August 8 (www.dmns.org/summernights).
About a year ago this very week, I met with Charlie Berger and Patrick Crawford of Denver Beer Co. to brainstorm experiments for our annual partnership beer for the Museum’s Young Professional event, Science on Tap. In the previous year, we brewed a historic kolsch with a native thistle to commemorate Denver’s brewing history. But for 2013, we wanted to get nerdier and more beery. So we honed in on flavor and the underappreciated role of yeast, and I was challenged to prove my microbial worth. It went something like this, “Nicole, you have a degree in microbiology, how about you isolate a wild yeast strain?” Me: “There are over 1000 species of yeast, the chances of getting one that ferments are slim to none.” My arguments went unheeded and soon thereafter I found myself agreeing to take the team into the wilds of City Park, armed with swabs, test tubes and a bet from Patrick that we could make beer from the isolated yeast. If we made beer, Patrick would “win,” and would get to be a curator for a day. If we didn’t make beer, I would “win,” and get to be a brewer for a day. (See full story covered in 2013 by Jonathan Shikes of Westword.)
Fast forward to July 2013, and we found ourselves in a draw. We had used our “call-a-friend” lifeline to Neva Parker from White Labs, and she helped us to actually isolate a yeast strain. Although we didn’t have enough time to sequence the DNA, and therefore didn’t know the species, we pitched it anyway and crossed our fingers. In the end we made a beverage—I’m not sure I would call it a beer, as the yeast was not exactly a happy fermenter. In fact, I think we drank mostly wort (read: slurry of unconverted sugars, and thus no alcohol). However, making good on this bet brings us to the present.
Patrick came to the lab yesterday to be a curator for a day, and we started by extracting his DNA to be sequenced. This was pretty sweet in and of itself, but we took it one step further and decided to get to work on this year’s installment of Science on Tap. Our beer collaboration—bringing together the minds of the Museum, Denver Beer Co. and Metro State University—will attempt to use archaeochemistry (the chemical analysis of archeological specimens) to find out what food and/or beverages were housed in ancient Maya and Moche vessels from the Museum’s collection. Then, once we have an ingredient list, we will brew a beer based off of what was in those vessels.
First, Patrick and I worked with Dr. Michele Koons, an archeologist who recently joined our curator ranks, to select two vessels that had a higher probability of having held a fermented beverage. Then, we placed those vessels in a sonicator, which uses sound waves to shake food and beverage nanoparticles left over from the pottery into a solvent. The samples Patrick helped us collect will be analyzed using gas chromatography. We hope that these experiments will give us clues to the recipes that were used to make fermented drinks consumed by the ancient peoples of the Americas. And if we can figure out these recipes, we’ll make a beer inspired by what we find and we’ll debut the beverage at Science on Tap 2014.
The team working on this project is a unique intersection of disciplines. Dr. Michele Koons provides the archaeological expertise on the collections and the ancient cultures; I bring molecular composition of food and taste expertise to the table; Dr. April Hill of Metro State University is our lead chemist; Dr. Hill’s graduate student, De Regan, brings all the elements of chemistry and archaeology together for her dissertation. Finally, the team is rounded out by our partners in beer experimentation, Patrick and Charlie at DBC who will ultimately use the art of brewing to bring this data to life.
A special thanks to many readers who sent comments and questions about the article I wrote on the Paleo Diet. It is really rewarding to get feedback from our members as this type of dialogue helps the Museum to fulfill its mission and vision which includes both creating a “community of critical thinkers” and “inspiring curiosity.”
In writing the article I had to do a significant amount of research, and was lucky to have the advice of Dr. Melissa Wdowik, a registered dietician, as well as from Lance Holly who is an anthropologist. Here is a rundown of the sources I consulted and my thought process as I tried to get a handle on all the information out there. If you have recommendations to me about other sources I did not consider, please feel free to send me an email and let me know. I think the Paleo Diet is a fascinating lens through which we can look at human health and evolution and I hope to continue to learn more. Your thoughts are greatly appreciated!
(This is a site that shows the data that is considered when compiling the Dietary Guidelines for Americans every five years. Click on the index to search topics. Within a certain topic, you can click on the review question that interests you most… bone health vs. weight loss will have different levels of support for example, then click on the evidence link to see all the references related to that topic. Each person will have a unique investment in the various health outcomes for each of the food groups listed below.)
Access to Articles: note that the abstracts of these articles can be found online through http://www.ncbi.nlm.nih.gov/pubmed/, the full article may require a subscription, but one can request a copy of an article by visiting a public library, or can (usually) have immediate access to the article by visiting a university library which likely already has a subscription to the journal.
Impact of milk consumption and resistance training on body composition of female athletes. Josse & Phillips. 2012.
Putting the Whole Grain Puzzle Together: Health Benefits Associated with Whole Grains. Jonnalagadda et al. 2011.
Essentials of Healthy Eating: A Guide. Skerrett & Willett. 2010.
Increased Consumption of Dairy Foods and Protein during Diet- and Exercise-Induced Weight Loss Promotes Fat Mass Loss and Lean Mass Gain in Overweight and Obese Premenopausal Women. Josse et al. 2011.
Role of dairy beverages in the diet. Weaver. 2010.
Invited review: Dairy intake and bone health: a viewpoint from the state of the art. Caroli et al. 2011.
Major scientific advances with dairy foods in nutrition and health. Huth et al. 2006.
Cereal grains and legumes in the prevention of coronary heart disease and stroke: a review of the literature. Flight & Clifton. 2006.
Bone Mineral Density and Food-frequency in Korean Adults: The 2008 and 2009 Korea National Health and Nutrition Examination Survey. Yoon et al. 2012.
Dietary and training predictors of stress fractures in female runners. Wentz et al. 2012.
The gourmet ape: evolution and human food preferences. Krebs. 2009.
Phytochemicals for health, the role of pulses. Rochfort & Panozzo. 2007.
Nutritional quality of legumes, and their role in cardiometabolic risk prevention: a review. Bouchenak & Lamri-Senhadji. 2013.
Potential benefits of adherence to the Mediterranean diet on cognitive health. Féart et al. 2013.
Identification of the flavonoids in mungbean (Phaseolus radiatus L.) soup and their antioxidant activities. Li et al. 2012.
The role of geography in human adaptation. Coop et al. 2009.
Diabetes Mellitus: A “thrifty” genotype rendered detrimental by “progress”? Neel. 1962.
Worldwide spatial genetic structure of angiotensin-converting enzyme gene: a new evolutionary ecological evidence for the thrifty genotype hypothesis. Li et al. 2011.
Evolutionary Aspects of Diet: Old Genes, New Fuels. Eaton & Cordain. 1997.
Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study. Jonsson et al. 2009.
The feasibility of a Paleolithic diet for low-income consumers. Metzgar et al. 2011.
A Palaeolithic-type diet causes strong tissue-specific effects on ectopic fat deposition in obese postmenopausal women. Ryberg et al. 2013.
A Palaeolithic diet improves glucose tolerance more than a Mediterranean-like diet in individuals with ischaemic heart disease. Lindeberg et al. 2007.
OUTSTANDING ISSUES NOT ADDRESSED
I also went back and read the FAQs on the Choose My Plate website, as there are many issues that aren’t really addressed in the guidelines, like celiac disease and lactose intolerance that can directly change the way that the guidelines are applicable to an individual. Here are some answers I found to these questions on this document: http://www.choosemyplate.gov/faqs.html
What is the difference between a food allergy and food intolerance?
For someone with a food allergy, proteins in certain foods trigger an abnormal immune response. Common food allergies include those to milk, eggs, fish, crustacean shellfish, tree nuts, wheat, peanuts, and soybeans. In comparison, food intolerances are due to the inability of the body to digest or metabolize a food component. For example, lactose intolerance is caused by a deficiency of the enzyme lactase that breaks down the sugar lactose in milk and milk products. Because food allergies and food intolerances can cause some of the same symptoms (stomach cramps, vomiting, and diarrhea) they are often mistaken for one another. Those who think they may have a food allergy or a food intolerance should be medically evaluated to avoid unnecessarily eliminating foods from their diet. Most people who have a food allergy need to completely eliminate the offending food and ingredients that contain the food's protein from their diet. However, for some food intolerances, like lactose intolerance, smaller portions (e.g., 4 ounces of milk) or a modified version of the offending food (e.g., lactose-reduced or lactose-free milk, yogurt, or cheese) may be well tolerated. More information about food allergies and intolerances can be found here.
What advice do you have for people who can't or don't drink milk?
For those who are lactose intolerant or sensitive to lactose, lower-lactose products are available. Hard cheeses and yogurt generally contain less lactose than milk and may be more easily tolerated. Some people may also try smaller portions of lactose-containing products (e.g., 4 ounces of milk) and/or combining the product with another food (e.g., having milk with cereal). Lactose-free milk is also widely available. Fortified soymilk (soy beverage), which has a similar nutrient profile to cow's milk, is another option within the Dairy Group. There are a number of calcium-rich, non-dairy foods for those who do not consume milk products for whatever reason (allergies, veganism, etc.). These foods include some green vegetables (collard greens, turnip greens, beet greens), white beans, canned fish (sardines and salmon with bones), and some soy products. However, consuming enough of these foods on a regular basis to meet calcium needs may be difficult for many. Calcium-fortified products such as juices, cereals, breads, almond drink, and rice drink can also be good sources of calcium. For more information on calcium sources, please see Appendix 14 of the 2010 Dietary Guidelines for Americans.
If I have diabetes, celiac sprue (gluten intolerance), food allergies, gastric bypass surgery, etc., how can I modify the USDA Food Patterns to fit my specific needs?
The USDA Food Patterns, based on The 2010 Dietary Guidelines for Americans, are applicable to healthy people over the age of two years. They do not take into account diseases or disorders that require therapeutic diets. For more information on a specific condition or therapeutic diet, please visit our Related Links page for government websites such as the National Heart, Lung, and Blood Institute (NHLBI) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).
OTHER RESOURCES I USED
A recommended resource from ChooseMyPlate.gov was www.healthfinder.com. While it was more of the same in terms of reiterating the guidelines, I did think it had one really great tip- tracking your changing eating habits. This application is worthwhile in order to see what really works for you in an objective way- tracking and comparing what you are doing and what is helping you reach your health goals (weight loss, increased muscle mass, lower blood pressure etc.) http://www.healthfinder.gov/HealthTopics/Category/nutrition-and-physical-activity/nutrition/eat-healthy
Making small changes to your eating habits can make a big difference for your health. Keep a food diary to track this. Knowing what you eat now will help you make changes. Starting today, write down:
When you eat
What you eat
How much you eat
Where and with whom you eat
How you are feeling when you eat
If you have specific questions, it is a good idea to work with a dietician to make sure you can have concerns addressed and to make sure you are not excluding any nutrients inadvertently when you make changes to your diet. To find a registered dietician visit http://www.eatright.org/
“Making the right food and nutrition choices is a necessary part of daily life—but finding the best and most accurate information can be confusing. However, it is possible to develop a plan for healthy eating, and plans that emphasize a balance of foods, like those based on the Dietary Guidelines for Americans, can promote positive lifestyle changes. An understanding of what is in the food we eat is essential for allowing all foods to fit into an eating plan—as long as they are consumed in moderation and combined with regular physical activity. Research studies and breaking news about food and nutrition appear in headlines almost every day. With so many changes, it can be difficult to tell which recommendations are based on strong scientific evidence, and which are simply marketing materials. Registered dietitians are food and nutrition experts, translating the science of nutrition into practical solutions for healthy living. Various tools are available to help meet the goal of a healthy weight. Among these is the Body Mass Index (BMI), which can be used as a screening tool to identify potential health problems.”
What are the major themes of the 2010 DGAC Report?
The DGAC considers the obesity epidemic to be the greatest threat to public health in this century. Each section of the Report was developed in a way that addressed the challenges of obesity. Another major theme was a focus on children throughout the Report. The Report included four major action steps for the American public:
Reduce the incidence and prevalence of overweight and obesity of the US population by reducing overall calorie intake and increasing physical activity.
Shift food intake patterns to a diet that emphasizes vegetables, cooked dry beans and peas, fruits, whole grains, nuts, and seeds. In addition, increase the intake of seafood and fat-free and low-fat milk and milk products and consume only moderate amounts of lean meats, poultry, and eggs.
Significantly reduce intake of foods containing added sugars and solid fats because these dietary components contribute excess calories and few, if any, nutrients. In addition, reduce sodium intake and lower intake of refined grains that are coupled with added sugar, solid fat, and sodium.
Meet the 2008 Physical Activity Guidelines for Americans.
Public comments address other issues and potential gaps in the Dietary Guidelines
This document may be a useful resource for others that have similar questions and places they may contact for more information.
For example, these comments address celiac disease and gluten:
Comment Number: 001364 “I was amazed that there is only a brief reference to Celiac Disease in the Guideline. The safety of foods for those required medically to follow a gluten free diet is not mentioned
as far as I could see. This is particularly important to those of us who need to follow this diet, especially as it relates to food manufacturing and food labeling. With the large
number of citizens who need to be assured of the safety of foods labeled "gluten free", shouldn't this be addressed in this report, rather than emphasizing only allergies? The
danger to those of us with Celiac Disease is the impact foods with proscribed grain sources has on the overall body for longer periods of time.”
Comment Number: 001371 “Gluten Sensitivity-- Have labels that ensure that things that have 'gluten free' are in fact 'gluten free' and also free from cross-contamination (e.g. cereals that say 'gluten free' that aren't produced in a dedicated assembly line. These products frequently make me sick, because of cross contamination. Perhaps a new ingredient 'contains gluten' being required for all foods that contain gluten of any kind (esp. modified food starch).”
Did the public have an opportunity to give input on the DGA process?
A public comments database was accessible for providing written comments and submitting support material. A total of 765 written comments on the DGA process were posted between Oct 15, 2008, and April 29, 2010. A total of 1,159 comments on the DGAC Report were posted from June 15 to July 15, 2010. Oral testimony was heard at the 2nd DGAC meeting and at a public meeting on the DGAC Report in July 2010. A total of 51 organizations or individuals provided oral comments on the DGA process on January 29-30, 2009 (2nd DGAC meeting), and 50 organizations or individuals provided oral comments on the DGAC Report on July 8, 2010.
How was the DGAC deliberation process made transparent for the public?
The public was encouraged to submit comments and observe the first two DGAC meetings in person. They were encouraged to submit comments and view the remaining four meetings by webinar from 4 around the globe. A www.dietaryguidelines.gov website was developed to provide one-stop DGA information. Transcripts and meeting minutes for each DGAC meeting and archives of each webinar are available on the website. Outside speaker presentations and data charts were also posted to the website. In addition, all meeting announcements and details were posted online. All Committee decisions were discussed in the public forum.
On the bristling cold morning of January 23rd, exactly one month prior to the opening reception for BMoCA's 2012 spring exhibition, I parked my truck in front of the studio and home of Viviane Le Courtois. About a week or so earlier I had received an email from the Museum highlighting the new exhibition Edible? and as a scientist who studies taste and health, I was more than stoked to find out more from the artist herself.
"What does it mean for something to be edible?" Le Courtois asks, gesturing towards the diverse objects that surround us in her studio space. She carries with her a French accent from growing up along the Brittany seaside, and in her hand grasps a iron mold of an artichoke. Beside her are boxes of handmade clay pots to be used during the exhibition for drinking herbal tea. Her petite form backs to a life-sized sculpture of an obese child, made from colorful mini marshmallows. Beneath her desk and on each windowsill are seedlings of herbs and sprouts.
I know the question is rhetorical, and yet I grasp for an answer, recalling what I have chosen to eat and what I have decided along the way was inedible. And I realize that the true answer is more personal than I'd imagined because it depends on your own unique perspective. This particular perspective is shaped by two things in your life: genetics and environment/experience.
Genetics. If you'll humor me in my favorite analogy (which I hope you'll find exceptionally appropriate to this post), your DNA is like a cookbook for your body. And like any good cookbook, your DNA contains recipes, about 25,000 recipes in fact. These recipes are called genes. Genes, like recipes, are specific instructions to tell your body how to make one important thing it needs to survive. These "things" are called proteins, and they are the mini machines in your cells that are responsible for how your body functions.
So back to Edible? … there are approximately 60 genes* that are linked directly to your ability to perceive various taste qualities (sweet, sour, bitter, umami (think meat) and salt). These genes give the instructions for how to make proteins that act like gate keepers in the taste buds on your tongue. Depending on which of the 5 tastes we are talking about, these proteins either bind small food molecules or will let molecules into the taste cell (see oversimplified taste cell below). Once a taste cell is activated in either of these ways, it sends a signal to the brain about what the taste is and how strong it it-this is how genetics can affect your perception of what is edible and what is not. The brain then takes that message and acts on it. "Should I spit this out or should I eat more?"
Environment/Experience. Thousands and thousands of years of evolution on both the genetics of taste and the way the brain responds to taste/consumption has put modern day populations in a sticky situation. We have been trained to crave umami, salt and especially sweet, with the goal of survival. The protein we eat is broken down in our digestive system into building blocks that will be used, based on the instructions from our genes, to make our own proteins. Salt is required for homeostasis (a balance in your body with the environment) and also provides the ions needed for the chemical reactions in your cells. And finally glucose- the simple carbohydrate that when combined with oxygen in the reaction of respiration makes the energy our body needs (and has the side products of water and carbon dioxide). During nomadic times of hunting and gathering, it was essential to find and consume foods that contained these necessary molecules. Because of this, we evolved to feel good not only when we eat these foods, literally, chemicals are released in the body akin to the experience of pleasure, but also in anticipation of eating these foods. Both can excite the reward center of the brain. This evolution of how our brains and bodies respond ensures survival, because it ensures we will repeat the activity that made us feel so good.
But what about now? As we have been wired based on survival in inhospitable environments, meats/ salt/sugar still excite the reward center of the brain. Yet our world is very different from that which we evolved. Industrialized nations have taken away much of the inconvenience and difficult work of finding food sources. There are convenience stores with prepackaged and highly processed food snacks and nearly a fast food chain on every other given intersection. And interestingly, a very cool research study published in 2008 shows that it is even worse than we thought. The reward center for obese teens is excited MORE in anticipation of food compared to lean teens. In contrast, the reward center for obese teens is excited LESS during actual consumption of the food compared to lean teens. So basically, obese children crave food more, but don't get the same pleasure hit when they eat compared to lean children. This means they have to eat more to get the same level of reward, making it very difficult to change unhealthy behaviors.
On the flip side of the equation, foods that are bitter often elicit a response akin to repulsion. Yet there are entire families of vegetables that taste bitter. Depending on what was made available to you as child plays a large role in conditioning us to like healthier food choices, including bitter vegetables. It begs the question, "What are we making available to our kids?" Most neighborhoods don't have local grocery stores. Farm products don't have nearly the shelf live as processed products and require preparation, so aren't as enticing to buy. There is significant concern over urban and rural food deserts. And while urban gardening is on the rise in Denver, the idea of a backyard garden is not one that is considered broadly. Modern day environments, therefore, plays such a large role in perception, because where you grow up and how food was presented to you has long term effects on how you perceive foods and the habits you pass on to your children.
This dichotomy of taste perception and behavior is thoughtfully constructed in Le Courtois' studio. Figurines of obese children, made from candy and each with a unique colorful glaze, line up like militia on a side table. Drawn to the rainbow of colors, I ask what was used to give the sculptures such hues. She explains the process of melting down candy pieces and pouring the liquid into a hand-crafted mold. That's it. The simplicity strikes me, as does the implications. Many of the sculptures were made years ago, and yet look as if they were crafted only yesterday. The medium she chose, it turns out, is just as important as the content. I contemplate this as she shows me sketches of the exhibition install and describes the emphasis on experiencing both ends of the polarized food world. As the light moves in the studio, I know I must say my goodbyes and head back to the Museum. The seedlings pale green leaves glow with the sun's changing position and I notice the shadow is now moving across the army of candy children. I find myself thinking that the sum of the whole is greater than the sum of the parts when art and science intersect in the realm of the human experience.
For more information about what you read about here, check out any of these links:
Science at Altitude:
Sports Authority Field at Mile High is exactly that -- at a Mile High, 5280 feet above sea level. High altitude means two things in terms of oxygen and decreased air pressure:
1. Less oxygen molecules
2. Less air pressure to help push air into our lungs when we breathe
These two factors cause hypoxia (no or low oxygen getting to the cells in your body). Why is oxygen so important? Oxygen is a key factor in how our cells make energy. When cells have oxygen and glucose (sugar) a reaction occurs that makes energy (in the form of ATP, the body's energy currency) and has the byproducts of water and carbon dioxide.
So without oxygen, our bodies can't make energy efficiently and our cells, tissue and eventually organs can stop working. This is what happened to Ryan Clark last time he played at Mile High, except his situation is even more complicated, because of having sickle cell. But let's look at what the body normally does, and then we'll take a closer look at sickle cell at high altitude.
For folks coming in from sea level, like the Pittsburg Steelers for the 2011 playoff game against the Broncos, there are two stages of adaptation the body must go through to ensure oxygen levels stay topped off within the body:
1. Short term adaptation: The body immediately starts to concentrate red blood cells (which contain hemoglobin, the molecule that carries oxygen) by filtering out liquid from the blood. This is why when you first come to high altitude you will have to go to the bathroom more and part of the reason why dehydration can be such an issue.
2. Long term adaptation: The kidneys immediately start sending chemical signals (erythropoietin) to the bone marrow to get them to make more red blood cells (and therefore more hemoglobin molecule in the red blood cells to carry oxygen). Over a period of time (anywhere from a few days to a couple weeks) a person will have topped off their red blood cells.
In the case of Ryan Clark and folks with sickle cell, this process is complicated. Your DNA is like a cookbook for your body. Each recipe in the DNA cookbook is a gene, and tells your body how to make one important thing your body needs. People with sickle cell disease have a change to the recipe/gene that tells the body how to make hemoglobin. Since hemoglobin is located in red blood cells, the molecule affects the shape of these cells. Normal hemoglobin allows red blood cells to be circular; with sickle cell the shape of the red blood cells is more crescent-shaped. The sickle cell crescent-shaped red blood cells can clog up blood flow, restricting the ability for the blood to deliver oxygen to cells around the body.
This is a genetic disease. Since you get one copy of each gene from mom and one from dad, a person can have two mutated copies, or sometimes might only get one mutated copy. With two mutated copies of the gene/recipe, the disease is more grave then having only one copy of the mutated gene because all the hemoglobin the body makes is from the mutated recipe, so all red blood cells are crescent-shaped, increasing the chances that blood flow will be restricted. My understanding is that Ryan Clark has only one mutated gene/recipe for making hemoglobin (he got one normal gene from one parent and one mutated one from his other parent), and so for the most part he is asymptomatic under normal conditions.
At high altitude however, your body is concentrating red blood cells. For folks with sickle cell, this means the body is increasing the number of sickle cell red blood cells in the same amount of liquid. This dramatically increases the chance that the sickle cell crescent-shaped red blood cells will clog up the arteries and therefore restrict blood flow, causing cell death, and organ failure.
Your body is a complicated and fascinating thing, and the more we understand about how genes/recipes work, and how the body reads and makes things from recipes (gene expression) the more we will understand both health and disease.
If you want to how your body adapts to high altitude and will be in the Denver area, come visit Expedition Health at the Denver Museum of Nature & Science, which takes you on a virtual hike up Mount Evans, a Colorado fourteen thousand feet peak, and shows you how your body changes in ways you can see, measure and optimize.
Taste is fascinating, complex, and it turns out, very misunderstood. I love that the sense of taste was highlighted recently on both Science Live and picked up by Fox News online, but found myself editing the generalizations and inaccuracies in my head as I read on, who knew I was such a stereotypical scientist?
Here's the deal, and why I'm so jazzed up, taste is not flavor; this is a big misconception and one that is perpetuated in the recent taste articles. Many things contribute to FLAVOR (i.e. the sensory perception as you eat), smell, mouth-feel among others, and of course taste. But don't fall victim to confusing taste with flavor. We may say something "tastes" good, but what we really mean is that we like all the sensations that come together to make flavor. So no, texture and smell do not affect how we taste food, they affect how we perceive food as a whole.
We all know about the 5 tastes: salt, sour, umami, sweet and bitter. But what about the chance that there are more? I agree with Micheal Tordoff, a behavioral geneticist at the Monell Chemical Senses Center in Philadelphia, when he is quoted in the article, relaying his opinion that "There is no accepted definition of a basic taste. The rules are changing as we speak." In fact there was a great session that Dr. Tordoff led at the 2011 annual taste and smell meeting (Association for Chemoreception Sciences) called "Basic Tastes- Why Five?" This innovative session gave the podium to scientists pushing the limits on defining new tastes, and reiterated the rules we currently have in order to determine what is really a "taste" and what is not. While it's true that there is no 100% accepted definition, there are some basic guidelines that are pretty widely held concerning if a "taste" is really a "taste":
1. The is a evolutionary benefit to recognizing the taste (makes sense that we have it)
2. There is a defined stimuli that causes a person to identify the taste (there is a tired and true food/chemical that causes the taste)
3. There is a specialized transduction mechanism for the taste (how the tongue gets the info to the brain is unique to the taste)
4. The signal must originate and be conveyed by the taste system (i.e. the tongue and associated cranial nerves)
5. The taste must be perceptible and unique (you must actually taste it and it must be unique)
6. The taste must evoke a response (tasting causes a reaction… i.e. Yum! or Blech!)
That said, I agree with the fact that fat, calcium and maybe metal all may one day be considered true tastes. However, where I think there is a lot of debate surrounds the potential "tastes" that are really sensitivities by the trigeminal nerve, i.e. this cranial nerve has free nerve endings that are like live wires on your tongue and are the ones that help you detect texture (anything with mouth-feel), temperature (hot cold, mint etc.) and pain (capsaicin in hot pepper).
These are not the sense of taste, they are the sense of touch and are sent to the brain by the trigeminal nerve. There is so interesting new opinions on these sensations, but not a whole lot of scientific evidence that points at a new "taste". Taste is a part of the flavor experience, but taste is only one part and it is very distinct in how it works and what it helps our brains to understand about the world around us.
Final word, even if receptors exist on the tongue for a new "taste", if we are not conscious of the reaction, is it a true taste?
But I've been back logged on my science reading the last few months and just got to the September issue that was buried under stacks budgets and grant ideas. I'm so glad I didn't just file it away with its buddies, because the very last page of each issue is "Small Things Considered" in which the newly coined holobiont was used.
The whole kit and caboodle- including the whole host (think YOU) and every symbiotic organism living with it (bacteria, viruses, fungi etc.)
The cool thing is we often think about evolution based on how well our gene products allow us to survive in a certain environment, standard evaluation dogma. But more recently scientists are realizing its so much bigger than just genetics. Epigenetics has come along and shaken up how we think about gene expression, and now the concept of holobionts to shake up how we think about evolution. Basically, natural selection occurs not just to the host but the host with all its little buddy symbionts, such that adaptation and survival are a team effort.
As the saying goes, there's no I in Team, and maybe not in Natural Select(i)on.
It is 2011 Nobel Prize week. It's a reminder about how incredible the human mind is, and how there is an entire world of discoveries just waiting to be made. Here's a quick look at the history of the prize and some of my favorites.
In 1895, a man named Alfred Nobel in Sweden penned his last will and testament leaving the majority of his wealth to begin the Nobel Prize. The first prize was awarded in 1901 and since has honored men and women from all across the world for outstanding achievements in physics, chemistry, medicine, literature, and for work in peace. http://www.nobelprize.org/alfred_nobel/biographical/
For me, the prizes awarded in physiology and medicine have truly impacted not only all human lives, but my career as a scientist. They answered questions about how we know a disease is casued by a bacteria, the sturture of DNA, and just how viruses can actually cause cancer.
Here are some of my favorites:
1905: Robert Koch was awarded for his work on tuberculosis, tied famously to the Koch postulates that establishes the relationship between a disease and its microbial cause.
1962: Watson, Crick and Wilkins were awarded "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material".
1975: Truly near and dear to my past self as a graduate student working on way cells can defend against viruses, was the prize awarded to David Baltimore, Renato Dulbecco and Howard Martin Temin. They were awarded for "for their discoveries concerning the interaction between tumour viruses and the genetic material of the cell".
I've had a collision of thoughts (mine and others) over the weekend and into this Monday morning, all dealing with scientists and communication. I love when that happens; all fronts meet in the middle and you realize that crazy idea percolating in your head is at the edge of others minds as well. My dad calls this occurrence "antennae", as in when multiple minds seem to engage it's like having your "antennae up."
Today, my antennae are up and tuned into making scientists better communicators. I was answering some interview questions from a writer named Thorin Klosowski at the Westword this weekend in preparation for the Sci-Fi Film series I'm a part of this Wednesday. He asked, and poignantly so, "Do you think ethical concerns would outweigh the benefits if Gattaca was ever a reality?"
There are huge benefits to understanding our own genetics, including understanding the genes and mutations involved in disease, customized and personal medicine based on genetics (pharmacogenetics) and genealogical research. But it's not just genetics; it's really what our bodies do with the recipes that make this information so important. We haven't really reached a point yet where that type of analysis is done in a way that is efficient and cost effective.
I think in order to answer this question as a society it's important that there is always an open discourse between those to the right and left of the issue, so that neither extreme mandates what we do with technology. What is most dangerous is not having honest dialogue, because that's when genuine concerns are not considered or equally worrisome, necessary scientific developments are halted by those that don't fully understand the technology There was a quote from Dr. Chad Nusbaum of the Broad Institute in 2007 that I think hits the question on the mark."Science is moving way ahead of the ethics. We can't stop the technological advancements but the gap keeps widening. It is our responsibility to understand the implications of our work and educate the public and elected officials so that a proper dialog can take place." (Reference http://www.genengnews.com/gen-articles/1-000-genome-remains-the-holiest/2000/)
What I realized, is that it's all fine and well for scientists to get out there and communicate, but in actuality, scientists have little to no formal training for communication with a general audience. We kind of stay in our labs/holes etc. and crank out the data, present at conferences to peers, hopefully publish a paper, then lather rinse and repeat. It's not very often that a scientist gets the chance to really share and collaborate with their community outside the walls of their niche discipline.
Here's why I'm stoked, this is something that the Museum is concerned about. Our chief curator, Kirk Johnson, PhD, has been keeping this at the forefront of our minds and our job descriptions. Sometimes it feels like a losing battle, how do we compete in a cut throat world of publish or perish if we spend 1/3 of our time communicating our research and not actually doing research? He sent us this link ( http://www.good.is/post/poptech-2011-science-and-public-leadership-fellows-announced/ ) this morning, about a new wave of support for scientists who can talk in plain and understandable language and who ultimately can make their science relevant. My antennae are up and I'll be right there in line supporting this effort to get our neighbors, friends, and communities engaged in a two-way dialogue with the scientific research in their backyards.
Background: When cells want to divide and make daughter cells, they need to first make copies of their DNA (shown as smiley faces in the cells above) so that both the original cell and the daughter call both have the same DNA (instructions) for making the cell work properly. Many organisms, like humans, have double stranded DNA in the form of the double helix (like a twisted ladder). The sides of the ladder are the complimentary strands of DNA twisted together.
To copy the DNA, the DNA ladder is unzipped to access sequence of nucleotides (A, T, G, and C) the letters that make up the DNA alphabet. The order of these nucleotides, just like in a book, spells out exactly how to make different things the cell needs to live. When the order gets messed up, or parts of the sequence are deleted, the cell has problems making the things it needs and can die depending on how big or important the change is. So when the cell copies its DNA, it has to do it very carefully.
This is no problem for one strand of the DNA, called the leading strand. It get read in a specific way by using a dock (small piece of RNA, kind of like DNA) that matches the beginning in order to start making a copy, almost like putting your finger at the beginning of the sentence and reading left to right in the English language (5' to 3' in the DNA language). The other strand though, called the lagging strand is the compliment of the leading strand, and so it is also read left to right, but the order of the letters is backwards. So the cell has to read by jumping forward in short stints to read the order correctly. It would be like having a book be written in reverse (down would be written "nwod"), and you put your finger a few words into the first chapter (covering a word or two) and then read in reverse move forward a few words, make a copy and then have to move your finger to the next few backwards words, continuing on until the end of the chapter and then connecting all the fragments by filling in the words that your finger had covered initially.
But there's a problem, the very last section of the chapter you read you have to put your finger down knowing that whatever your finger covers on this last bit, you won't be able to fill in because there is nothing after it (this is the last Okazaki fragment). Scientists know this to be the "End Replication Problem" because towards the end of the lagging strand there's not enough room to place your finger and still read the last words to copy them.
The blood test just released in the UK doesn't look at the part of the DNA that contains the instructions for your cells; it looks at the end part of the DNA, called telomeres. Telomeres are how the cell solves the "End Replication Problem" by giving a little bit of extra sequence at the end to fill in gap in instructions. So the ends of the DNA, which do not give instructions to the cell, do undergo shortening over time in order to prevent the instructions in the center part of the DNA from being subject to that shortening. But all good things must come to an end, and eventually the telomeres are exhausted, cycles of copying leaving them diminished, and leaving the DNA open to progressive shortening in the instructions section.
As mentioned above, any time you have significant changes or deletions in the DNA, it can affect survival. The "Hayflick Limit" is the theory that when the telomeres run out, the cell dies. Although a hypothesis, there is mounting evidence that this might be true. The scientists behind the UK blood test are cashing in on this hypothesis by correlating the length of a person's telomeres to how much longer their cells and therefore they will live. These questions remain: what is the science behind this correlation, how accurate is the prediction, and what are the repercussions of this knowledge to the person seeking it and to others if it were to get in the wrong hands?
First it was the tongue, then the guts, then the lungs, now researchers have found evidence that there are bitter taste receptors in the brain! Why? The scientists think that the activation of bitter taste receptors in the brain increases calcium in brain cells and this increase in calcium leads to the production of chemicals in the brain that regulate food intake.
Questions to think about:
1. What is the actual ligand (the bitter chemical/molecule) in the brain that activates the taste receptors? This study uses quinine as a ligand to prove that the cells are there and can be activated, but the scientists add the quinine specifically to see if the cells react.
2. What concentration of the ligand really needs to occur naturally in the brain for the receptors to be activated? There is proof that quinine can cross the blood brain barrier, so if the ligand is quinine, how much needs to be around for the brain cells to be activated by it?
3. What is the true physiological affect of having brain cells express taste receptors that can be activated by bitter compounds? Scientists would need to do experiements that study behavoir to know if the activated cells either stimulate or block food consumption.
3. This study was done in rats, would scientists find the same receptors in human brain cells? Does this affect how much we eat?
Monday mornings I sort through the weekend's long trail of emails. As part of this routine, I receive my weekly search results on "chemoreception" from pubmed.gov-- an online database of biomedical publications. Usually I scan the titles and chalk it up to a "read later" file in my head- not today.
Today, there was one title that really caught my eye, "Functional Bitter Taste Receptors are Expressed in Brain Cells." I clicked on the link to read the abstract, crossing my fingers that I had access to the full paper (sometimes publishers don't allow open access for up to a year after publication).
It turns out, it's not the newest of news, as the study was published in March, but it's new to me because my search filter only pulled it up today, a good 2 months late for some reason. I read on with interest and found that the study was done in rats, and the scientists show evidence that yes in fact, at least in rats, the animals have bitter receptors that in their brains that when they bind bitter chemicals, it activates the cell.
What's interesting will be to see if there are taste cells in the brain that are similar to taste cells in the tongue (within taste buds, shown on the left) and to the taste cells that have been found in the digestive system (shown on the right). Both of these cell types are shown below with the signalling pathways that occur once the cell is activated by a taste molecule. (This image is from a paper published by David E. Cummings and Joost Overduin in 2007.)
I don't have access to the full paper "Functional Bitter Taste Receptors are Expressed in Brain Cells", but the authors indicate that they discuss the physiological relevance of this in their results section. I don't know much about the anatomy of rats, so I can't guess what the authors discuss, but it is important to note that although mice and rats are studied to understand mammalian biology, and although there are many genes that are similar between these groups, results in one species does not necessarily mean you will find the same results in another species. This point that was made clear in the recent AChemS (Association for Chemoreception Sciences) meeting I attended in April, where even distinct differences between mice and rats in terms of taste and smell were discussed. So it is unclear at this point if mice or even humans also have bitter receptors in their brains.
I want to also note that these authors were not at AChemS, and so I don't have any insight from the meeting on the general feel for this new discovery among other taste and smell scientists. I did a quick to search on Bing to see if the story had been picke dup elsewhere, but I couldn't find any other information. If I learn more from my colleagues at the Rocky Mountain Taste and Smell Center, I will put it up on the blog as a follow up post.
Until then, for those of you who are interested, you can read the abstract HERE
New Frontiers in Chemesthesis: pronounced keem-E-thesis, think perception of pain, temperature, and touch (can be used in all sensory organs)- in the mouth it includes pain from capsaicin in hot peppers, menthol cooling sensation, and the signals are sent to the brain through cranial nerve V- the trigeminal nerve.
Synonyms- irritation, common chemical sense. A stimulant that is perceived and the body reponse.
Today's excellent talks which included these cool data:
1. "Toothache tree" Zanthoxylum (peppercorns) contains hydroxy-alpha-sanshool. This compound causes "tingling" when used topically. Dr. Diana Bautista (I'll get a video embeded above) showed that the mechanism of this natural pain reliever was not due to the same ways that capsaicin or mustard seed works, and that it can reverse mechanical (touch) sensitivity when skin is inflamed.
2. Oleocanthal, a chemical in extra virgin olive oil (EVOO as Rachel Ray would say), is pungent to the human oral cavity, Dr. Catherine Peyrot de Gachons found this mild irritation is due to the same mechanism of action as ibruprophen, it elicits the TRPA1 channel.
I woke up to the sounds of "Bell Tower" through my phone's alarm clock, and could not for the life of me understand why my husband hasn't hadn't hit snooze already, "but wait!" I realized groggily, "I'm in Florida, not in Denver, that must be the alarm I set last night." In a sleep induced haze I grabbed for my phone, dropped it inadvertantly behind the hotel bed (while it was still tolling away), finally got a handle of it and hit snooze.
Despite all this, I made it to breakfast by 7:45 am, filled up my neon green Denver Museum of Nature & Science travel mug with copious amounts of coffee and found a table to join. I had a great conversation with the folks at breakfast about how professional societies are taking a stab at social media, about Body Worlds, about anatomy, and about how to keep memberships in professional societies consistent year to year. There was also talk of scuba diving and sun catching, proof that there is life outside the lab.
OK, so what did I learn today?
1. Meghan did an incredible job presenting this morning
2. A group from Monell has made a transgenetics mouse (they put one gene, called T1R3 from humans into mice that do not have the mouse T1R3) that has the ability to "taste" sweet like a human would taste sweet- making a great model for studying behavoir and other aspects of taste.
3. The difference between habituation and adaptation. "Habituation is when the brain still gets a signal, but doesn't care. Adaption is when the sensory cells no longer send a signal to the brain." Dr. Yanina Pepino explained. She presented research showing that obese and lean women do not have a difference in the initial pleasantness or intensity of sweet foods, but lean women habituate to the pleasantness more quickly than obese women, and so stop eating earlier.
Optogenetics is not the newest craze (dates back to 2002), but it has huge potential and momentum (one peer reviewed article in 2006, exponential growth predicts 280 scientitsts will publish using this method in 2012).
Optogenetics allows scientitsts to selectively express a gene in neurons that allows that neuron to respond to light- at the SINGLE neuron cell level. Pretty cool.Dr. Diego Restrepo from UCD describes optogenetics in broad terms in the video above.
Dr. Jessica Cardin from Yale gave a more in depth overview this morning.
She made an incredible point that I hadn't thought of: when you allow a neuron to express a gene that responds to light, that response is all over the neuron, not just in the area of the neuron that normal creates an action potential during regular activation. In the picture below you can see the little blue lines (look closely on the neuron to the left) that represent where on the cell to are the specific parts that respond to light- and they are everywhere. Compare that to the neuron on the right (a regular neuron) that is acivated in the axon (big red center part) and sends that action potential out from the center.
What does this mean? I think its a great lesson that scientific techniques are constantly evolving to be more nuanced, but they are never perfect, as science is never perfect. It reminds us to think critically about data and the methods we use to get data, but more so to be critical about the conclusions we state, as that has implications well beyond the front and back cover of journals.
Want to know more about optogenetics? You should, it was made the Nature METHOD OF THE YEAR in 2010. Pretty impressive. Nature put together a 4 minute video that does a great job putting the words of this method in images. Check it out here: http://www.youtube.com/watch?v=I64X7vHSHOE
I will be completely honest with you, I had no intention of blogging about this trip to Portland for the National Institutes of Health (NIH) Regional Seminar. I suspected I would man the Genetics of Taste lab Wednesday morning, fly out of DIA, land in PDX, attend the conference and thus figure out how to get our next round of funding for our research, fly home, write grant and call it a day. Grants aren't exactly a lively blog topic, especially science grants.
Well, I was so wrong (at least I think I was, you'll have to decide for yourself if my NIH experience merited blogging). The 2-day conference has been actually entertaining (in addition to the known quantity of educational) and absolutely worth giving my Blue Tongue Blog audience at least a taste of. How could I not, when Dr. Sally Rockey, acting director of extramural (read: grant) research kicked the first session off with a segment of the Colbert Report. I was immediately won over (video link here for all that are intrigued, if the link doesn't work, goggle or bing "Francis Collins on the Colbert Report").
So, what is the NIH anyway? The NIH (highlighted below in blue) is a division under the large government umbrella of Health and Human Services (HHS).
The acronym NIH stands for the National Institutes of Health, emphasis on Institutes- plural that is (see below). It is a collection of 27 Institutes and centers, each with a unique mission, priorities, budget and funding strategy.
Second row from the bottom, fourth from the left you'll find the National Center for Research Resources or NCRR. It is under this center that our Genetics of Taste: A Flavor for Health grant hails, as a Science Education Partnership Award (SEPA). As the name implies, our grant is not just for traditional bench or clinical science, but rather a true pairing of educational and science resources.
Finally, I learned today that all funded NIH grant titles and abstracts are available online. So you yourself can see just how novel our SEPA project is for example, or you could take a peak at the funding behind something else you might be interested in, perhaps Alzheimer's or obesity. It's all there. In fact, beyond transparency, the NIH requires authors of scientific articles to make the published papers available a year following publication through the US National Library of Medicine http://www.ncbi.nlm.nih.gov/pubmed/ and is actively pushing grant authors to truly write and submit enthusiastic and compelling applications in an effort to make the best and most current scientific studies digestible by more than just the small niche of researchers. So I'll leave you with this final slide from Dr. Rockey, one that as a science communicator I hope researchers take to heart, and one that perhaps you all might also be encouraged by: science research in the United States is a intellectual and economic power that is for the people by the people and therefore open to the people.
I felt it coming on yesterday, the headache the itchy throat, the inability to focus.... I knew what was coming, I was at the cusp of coming down with something. Sure enough, I woke up this morning in a daze of achiness, swollen glands and complete congestion- YUCK! Plus the smell of freshly ground and brewed coffee that normally helps guide me out from under the sheets of slumber was no where to be found.
I forced myself out of bed and headed for the kitchen. There was coffee (phew! I knew I'd need it), and I was in fact hungry- so I popped a cinnamon raisin English muffin into the toaster. Now normally this makes the kitchen smell like a bakery, the enticing smell of warm cinnamon which makes my stomach growl and my mouth salivate. Not today. What was going on?
It turns out that I couldn't really experience the joy of eating my breakfast because of my congestion- plain and simple, I couldn't smell. I still could taste though! As I ate my English muffin with honey, I could still perceive sweetness, and when I drank my coffee I could still perceive it was slightly bitter (and I could feel the creamy texture of the half and half I added via the trigeminal nerve), but it was not as pleasant as it usually is because I did not have the entire experience of flavor perception, I was missing smell.
In the end, there was so little pleasure in eating that I didn't finish the English muffin or my coffee. I opted for some echinacea tea, cleaned up and made my way to work. For all you with cold, congestion or allergies, I feel for you!
As a lab that studies one form of chemoreception (aka taste), I could not resist sharing this dance video about the other form of chemoreception -- olfaction (aka smell). This is evidence that the nitty-gritty details of our scientific world can be communicated in a variety of interesting ways that compliment our regular conferences and peer-reviewed articles. Plus, it's great entertainment.
It is with this same enthusiasm, that I bring you epigenetics. It is fascinating, it has to do with humans, and scientists have no idea about the wonders they will discover as they dive deeper into this new field of study.
With that said, I'll be the first to admit that I find epigenetics daunting, and I often struggle in explain it our volunteers in Expedition Health here at the Museum. This can be frustrating, I'm a geneticist who can't properly explain epigenetics. The reason I'm sharing this ego-shattering point-- because I'm not alone. A sigh of relief escaped my lips yesterday morning as I watched the worlds leading scientists in the field of genetics describe in epigenetics in a range of ways, openly discussing scientists do not agree on what exactly epigenetics is.
In addition though- I also found myself nodding and murmuring "ahh", "that makes sense" and other expressions of affirmation, because while epigenetics is still elusive, the culmination of their thoughtful responses at least gave me the courage to write this:
Epigenetics is beyond the sequence of the DNA, it allows for your cells to begin expressing a trait, or stop expressing a trait, without any change to the order of nucleotides in your DNA.
What this will mean mechanistically within the cell, scientists have only begun to touch on, but it's got my attention and I'm looking forward to learning more. If you'd like to learn more, this week's issue of Science dives head first into epigenetics, and kicks it off with the video I elude to above, which can be found here: http://videolab.sciencemag.org/Featured/650920373001/1
What a great year it has been for us in the Genetics of Taste lab, and it seems others are taking notice. I returned to the office to find a wonderful present from Rebecca Jacobson, a science and technology reporter for PBS- an article about our study, the citizen scientists involved, and cool quotes from some great taste scientists! A very happy holiday indeed and a great jumping point for the new year.
From PBS NEWSHOUR online...
Science & Technology Updated: Dec. 23, 2010, 11:57 a.m. ET
The Bitter Taste of Genetics
Cheek swabs, taste buds tests and tongues dyed blue -- it's all part of an experiment on taste genetics at the Denver Museum of Science and Nature. Reporter Rebecca Jacobson took a test drive through the tasting process.
"I think we have a taster! Maybe even a supertaster!"
That's what the Denver Museum of Science and Nature's curator of human health said, laughing, as I made a face. It was Thursday afternoon, and Nicole Garneau, the curator, and Patty Drever, a volunteer, had just swabbed my cheek and instructed me to lick a piece of bitter paper. Imagine black coffee grounds mixed with raw broccoli. To me, it tasted that bad.
In our Genetics of Taste lab, we study Tas2r38 (allows us to taste certain bitter substances), only ONE of the MANY genes that allow us to perceive taste, but just because here at the Denver Museum of Nature & Science we only study bitter doesn't mean we don't love each of the other tastes as well: savory (Umami), salty, sweet and sour.
So today, we decided to tell you more about these tastes and pay homage to the researchers who finally debunked the tongue map. You remember the tongue map right?
Well, there have been a series of studies that found that individual tasting cells are not actually found clumped together in distinct areas of the tongue as we once thought. Let's talk a little bit about each of these tastes.
Sweet: the ability to taste sweet tells our brain that our body is getting energy-rich nutrients (like carbohydrates).
Umami (savory): the "newest" known taste, it allows us to taste amino acids (like in meat broth) which are the building blocks of proteins that make our body.
Salty: helps our brain keep track of ions and electrolyte balance. Interestingly, the identity of "salt" receptor cells are still not 100% known. Although there have been many researchers that have published their results- there still is no consensus.
Sour: tells our brain that we are ingesting something acidic (and potentially harmful, like spoiled food).
And of course, there is Bitter: allows us to taste potential toxins (like from poisonous plants).
So what does this mean for us and our tongues if this map is so rightfully wrong? It means that each of those areas highlighted above contain bumps, called papillae, that contain taste buds- and these taste buds are made of a collection of cells, so you can have taster cells for different tastes in the same taste bud.
So the moral of the story: forget about using just the front of your tongue when trying not to taste the sourness of something sour- your taste buds are in every taste papillae and they contain cells that can taste sour, salty, umami, sweet and bitter!
What a day! There were so many fantastic posters today that I can't possibly report all of them. Luckily, so many researchers I spoke with were receptive to the idea of chatting more, so I've got some great information for future posts.
For now though, let's talk about Dali. There was a stint of time this afternoon that was wide open for exploring St. Pete's. I used the time to take in the works of Salvador Dali at the Dali Museum. I know this is a taste blog, but humor me while I address the sense of sight. Not a huge fan of Dali's surrealism, I today developed a newfound respect for the artist during my time at the museum. His work was surprisingly far-reaching and very diverse. There were paintings from his early teenage years that were truly extraordinary as he tried his hand at emulating some of the greats (Picasso and the like).
And yes, he does have a painting called the Birth of Venus, but that's not what this post will address. What I found there, in a section of the museum displaying gold jewelry and eccentric plates and utensils, was an unfinished oil painting on a gold cup, also entitled the Birth of Venus. The inscription, which you'll find below, was kindly given to me by a helpful docent there. I think, you will find it incredibly interesting.
You can see why I was so excited, I had no idea that the huge piece of topaz we have in our exhibit "Gems and Minerals" was originally part of a proposed piece of art.
This gem (pun surely intended) of a find today in the realm of surrealism, nicely leads me to another interesting tidbit I stumbled upon. The story goes like this, I invited a stray pair of scientists to join me for lunch a few days ago, as the seating was full and I didn't need to have an entire table to myself. In a lovely turn of events, the stray scientists were in fact some of the pioneering researchers of the gene Tas2r38, Linda Bartoshuk and Stephen Wooding.
The tidbit? Taste-altering consumables.
The first, called miracle fruit, I originally heard about from fellow curator David Grinspoon over coffee one Friday morning. I had completely forgotten about it until Steve and Linda began telling me about this thing called "Miracle Food" (or so I thought they said). They explained to me that it heightened the perception of sweet, making lemons taste like lemonade for example, and lemonade taste like, well like a sickeningly sweet liquid.
Tonight at the poster session however, I spoke with some other folks and they were talking about "frooties". I had no idea what a frootie was. "It's miracle fruit" I was told. Ah! Not miracle food, but fruit. So speaking of senses, maybe I need to have my ears checked.
So miracle fruit parties, where people experience tastes on a whole new level are all the rage it seems. What I imagine isn't, is the second tidbit, gynemic acid. You used to be able to get this in a gum form, but you can't anymore, only in tablets. Why wouldn't you want to have a gynemic acid party one might ask... well besides the fact that it just doesn't sound cool, it doesn't taste cool either. It takes away taste, so that sugar will feel like you are eating sand!
And well, as much I wanted to share more science with you I've reached my writing limit yet again, and sand reminds me that I'll be leaving the silky white sands of the gulf coast tomorrow to head back to what I hear has been a rainy spell in Denver.
So until next year, signing off from AChemS 2010 one last time,
The questions pertaining to researching flavor, I'm learning, go far beyond taste. Flavor is a combination of taste, smell and texture. Each of the factors then send signals to the brain (at the primary taste cortex) which allows it to form an internal representation of the physical and chemical features of what is being consumed.
Tonight I watched an exceptional presentation, from both a scientific and entertaining viewpoint. It was an overview of mammalian taste given by this year's IFF (International Flavors and Fragrances Inc.) platform lecturer, Dr. Charles Zuker.
Why exactly did I enjoy this lecture so? Very simple reasons:
1. It was directional and personable. It began wide-reaching, depicting perception of the world through each of the senses: hearing, sight, touch, smell and of course, taste. A bit of Mozart played in the background as the point was made that our senses allow us to capture the surrounding world in our minds, and not necessarily an exact picture, but a representation that allows us to make decisions and proceed. From there the details emerged concerning taste specifically. It was personable because the presenter was engaging- it felt conversational, even though I was one in a crowd of 500.
2. The story included the forest, not just the trees. I can tell you that when my life revolved around my lab bench, it was so easy to converse only with those that spoke the same language as I- at that time in my life it was the sweet lexicon of viruses. And let me tell you, when your life revolves around one very small portion of the world at large, and you know everything, and I mean everything about that one thing, It is easy to get lost in it. So I truly appreciate it when a scientist is conscious of this trait and makes an effort to present his or her research in a way that addresses the eternal question of significance.So then, why is taste so important? Well, you can't talk about taste without talking about health. And our decisions about how we treat our bodies, including what we eat, has to do with perception- the information the brain gets and what it does with it. Dr. Zuker aptly posed the following question:
"How does the tongue know what it is tasting and how does the brain know what the tongue knows?"
3. It generated a healthy discourse among experts. Science is funny, I mean it, truly funny. It is not a flowery positive world. In science, you can almost never, in the most absolute form, prove anything. What you can do is supply the most convincing evidence to bring forth a story, while simultaneously disproving other stories. This means that scientists are often uncompromising in their criticisms. If you can't poke holes in a theory, then the theory likely will hold up to the high standards of peer-reviewed research. Discourse in this way is good, it keeps scientists honest.
So, that's why I really enjoyed this talk, but not why I was fascinated. My fascination has to do not with the style of the presentation, but the substance.
The answers to the questions Zuker asked above about the tongue and the brain include knowing how the receptors of taste work, knowing how this information gets to the brain and knowing how the brain processes this information. This last part, well, Zuker is doing some really cool work to answer this with mice. What he has found is that its more than just a receptor (like a lock) that binds to a taste molecule (like a key), but it is also the hardwiring of how these receptors activate the taste cells that report to the brain. It turns out that if you take a bitter taste cell and replace the bitter receptors with sweet receptors, you get an extraordinary result: sweet compounds taste bitter!
Why is this? Well, the bitter cells are hardwired to report bitterness to the brain (like sweet cells report only sweet to the brain), so when the cell gets activated by one of its receptor binding a taste molecule (like turning on a light) it reports the light is on, regardless of how the light got turned on.
With that, It's about midnight or so here, so I think it's time for me to turn off a few lights myself.
Is it any coincidence that the last time I was at a science conference it was in Melbourne (Australian Society for Microbiology) , and today, after landing in Tampa Bay and hitching a ride to the hotel via Super Shuttle, the lyrics "I come from a land down under…" started beating from the speakers of the van?Men At Work: Down Under (worth a click, but only if the song is already stuck in your head!)I think it was fate telling me I was right to get back in the research saddle- and that the Denver Museum of Nature & Science was making its way to the premier meeting of taste and smell scientists worldwide.
So here I am, 11 pm EST, reporting live from the Association for Chemoreception Sciences.
In the six hours I've been in St. Petes (FLA) I've learned first and foremost that AChemS is pronounced A-chems (and not A-Chem-S) whoops!
Second, and this is likely because I'm by my lonesome- don't be shy. So even after only a day, I've made some great connections with both educational and scientific potential collaborators representing states from Michigan to California, from Mass to Tennessee, and even my old stomping grounds of New Jersey. So far, folks have been really receptive to the idea of public access to authentic research, and have nothing but praise for what we do in Lab Central every day.
So far so good, but maybe you're asking yourself why I'm here by myself in the first place? Well, I'll give you one guess…
Dr. Bridget Coughlin, fellow curator of human health, was to be my partner in crime here at AChemS. However a quick turnaround trip to Germany to secure a specimen for Expedition Health has turned into almost a two week sojourn in Berlin. She, like many other unfortunate folks who were to be attendees, is grounded. Who knew a little ash could be so obtrusive to the progress of science?
But speaking of attendees, I have some late breaking news for all you Coloradoans. Our very own Marco Tizzano from the Rocky Mountain Taste and Smell Center (UCHSC Aurora) has been awarded the Polak Young Investigators Award. I introduced myself to Marco after the ceremony to congratulate him. In a soft Italian accent he said, "I always thought my work was important, but it's good to hear it from others."
Scientists communicate in many ways, some which are far more entertaining then others.
Take for example publishing- a way to disseminate information in a peer-reviewed journal. A clearinghouse for these publications is run by the government and is called pubmed. While priceless, publications are not always the most effective or dare I say fun way to get information out to the world. Enter science meetings-- a few days once a year where scientists within a discipline descend on a locale and share their recent findings via presentations (talks) or by posters.
Here I am about a 2 hours ago, sharing the Museum's education and scientific objectives with my taste and smell colleagues. And below you'll find some of my favorite comments of the night as they pertain to DMNS and our new human genetics study on taste.
"Looks like you've got your plate full." (no pun intended?)
"Is this the next step in evolution for museums, perhaps and hopefully one that all museums will make?"
"In our research we only use male mice, females are complicated. We see stronger and more robust signals in data from males." This was in the context of our VERY preliminary data (which you can see below) which shows a slight shift to a lower percentage of body fat in men who are tasters vs men who are non-tasters,but no difference thus far in taster and non-taster females.But please dear and loyal audience, do not read too deeply into this, as the study has many more miles to go.
So in additon to ways in which to improve our research... what else did I learn today?
First, my brain uses loads of glucose to comprehend in-depth science from 8am to 11pm. Second, the talks and the posters are chock full of pertinent information. One of my favorite posters, in fact, was about the standardization of the "Food Liking" survey that links chemosensation (i.e. taste and flavor perception) with diet and health (Katryna Minski from Val Duffy's group). Also Hetvi Desai, from Greg Smutzer's lab, presented work demonstrating a new way to make edible taster strips- so cool- they dissolve in your mouth!
But I digress, what I really want to emphasize is the way in which science communication just happens when you least expect it, over lunch, a walk to the next session, or even in the elevator. I may not have solved the world's problems here today, but I sure did find some new and interesting ways to conduct our research.
Aw heck, how is it midnight again? 7 am will likely come too fast.