Addicted to “Food Addiction”

I recently wrote a short article on “food addiction” for the Risk Innovation Lab’s CrisBits blog (collaboratively published by Arizona State and Michigan University!). This piece mainly focuses on the scientific side of the issue- I really wanted to broadly cover research on the topic, since so many popular articles on food addiction focus on singular studies (and end up being extremely misleading). Yet I also really wanted to address the topic from an anthropological perspective.

… the notion of addictive foods attracts us on a much deeper level as well

So why are we.. almost addicted to the belief that “food addiction” is a thing? If you read my CrisBits article, you’ll see that there is (as of now) no actual evidence for any food ingredients causing addictive-like responses in humans. The field is highly debated, though: there’s plenty of scholars arguing pro and against. On top of that, the media often does a horrible job sensationalizing food addiction research (well, I suppose it does a great job sensationalizing, but a horrible job communicating the results correctly). All of that can surely create the illusion that science actually supports the food addiction theory. However, the notion of addictive foods attracts us on a much deeper level as well…

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The allure of addictive foods

There is a strong cultural appeal in the idea that certain “bad” foods or their components can cause dependence and are thus dangerous (e.g. MSG, casein, gluten). This view of overeating as addiction includes the need to “detox” and instead eat a “clean” diet (e.g. this: The Diary of a Sugar Addict in Detox).

These are not just modern health trends, but a manifestation of a need to understand our world by imposing structure and thus meaning on the untidy experience that is reality. Structure is created by categorizing things into clean/unclean, healthy/unhealthy, pure/dirty- and things that don’t clearly fit into such categories are considered unclean and dangerous. Anthropologist Mary Douglas makes this point in her seminal book, Purity and Danger, as she examines food taboos (cultural rules about what not to eat). Douglas points that prohibited foods are considered “polluting” because they defy easy classification into culturally important categories. The current unease with genetically engineered foods is a fantastic modern example: as a technology that blurs the lines between natural and unnatural domains, it is indeed often termed by opponents as “genetic pollution” or “contamination”.

…prohibited foods are considered “polluting” because they defy easy classification into culturally important categories.

The categories we create to make sense of the world have strong moral overtones, as they allow us to essentially define right and wrong. Indeed, the word “addiction” itself is connected to the moral disapproval of socially undesirable behaviors (e.g. drug abuse). Psychologist Paul Rozin points out how the fear of sugars in American diets, for example, reflects the Puritan belief that things that are very pleasurable must also be bad.

Religious Scholar Alan Levinovitz also emphasizes that people frame eating in terms of morality and religion. He discusses how concepts of healthiness reflect the “myth of paradise past”- the idealistic belief that things were better, healthier, and even morally superior before. From such perspective, novel changes to foods represent our fall from grace- whether via agriculture (e.g. as in paleo diet ideology) or industrialization and technology (as with processed and genetically modified foods).

So, that’s my little anthropological view of food addiction beliefs as a cultural phenomenon. Hope you enjoyed it!


P.S. You might see news reports on studies about food addiction.. but keep in mind that no clinical diagnosis for “food addiction” exists, and most such research uses a self-report questionnaire: the Yale Food Addiction Scale (YFAS). This tool uses DSM-IV’s generic criteria for substance abuse to measure addictive-like eating.

Most importantly, it does not validate the existence of “food addiction” as a true disorder (DSM diagnostic criteria is intended for trained clinicians, not a checklist for self-diagnosis via a simple questionnaire). This is a critical issue to consider, as most food addiction research with humans is based on diagnosing food addiction this way.

Time of Eating & Health: Video

I made my first science communication video! It took me only ~ 15 hours, no big deal 🙂

It won’t be as time consuming from now on..but there is a lot of work involved nevertheless: writing a good concise script, sketching all the images that could go along with it, setting up the recording (can be so tricky!), recording yourself draw (and redraw.. and redraw) every frame.. Then editing all those videos, recording the audio (and re-recording..and re-recording again), and finally matching video to audio (as well as finding some free background tunes to go along!). Check it out: 

 

I chose this topic because i’ve been craving to cover it for some time now. Since my dissertation work focused on lay models of healthy eating across cultures (so: people’s beliefs about what it means to eat well), I did not address the scientific accuracy of any perceptions. But oh I wanted to! And that is because one of the most fascinating findings from my interviews was that eastern European (EE) participants considered “how you eat” (i call these “eating styles”) to be more important for health than American respondents.

Eastern Europeans (EE) judged statements about EATING STYLES (such as time of eating) as more important for health…

Specifically, EE participants rated the statement “it is important to avoid eating late in the day” significantly higher than Americans (and this was true from my past survey-based studies!).

This is what the image below shows, but let me explain the method behind it: I conducted >70 interviews in the U.S., Romania, and Ukraine where I asked people to look at 42 different statements about “healthy eating”. Among other activities, they had to indicate how much they personally agreed with each statement (from “4” agree completely to “-4” disagree completely; I used Q Methodology for this, by the way ).

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So, between Americans and eastern Europeans, 1 statement about eating styles (or “context” as I referred to it in this chart) that was more important for the latter: not eating late.

So, out of ALL 42 cards, only “avoid eating late in the day” got a statistically significantly higher agreement score from eastern Europeans. AND when prompted to explain their views, my respondents gave an explanation that was amazingly close to the actual science of circadian rhythms!!

Why did EE folks seem to know about circadian rhythms way more than Americans?

I didn’t analyze why EE folks seem to know about circadian rhythms way more than Americans, but this knowledge is something they knew from childhood.. It was part of general recommendations and “common sense” while growing up in the USSR. It fact, importance of eating styles is prominent in traditional beliefs about health (like in Japan and China).. perhaps all the focus on nutrients that’s possible with modern science is taking our attention away from this old wisdom?

perhaps all the focus on nutrients that’s possible with modern science is taking our attention away from this old wisdom

Now that nutrition science is paying increasingly more attention to eating styles as well (CHRONO-NUTRITION!), I assume American folks will begin incorporating beliefs about importance of food timing also!

The “other countries banned it” argument

Posts like these.. drive me just slightly crazy these days.

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I don’t blame anyone for getting affected by them.. but let me tell you a little story about banning “bad” stuff by other more enlightened countries who are apparently less evil and profit-driven than US (insert eyeroll).

This summer I interviewed participants in Ukraine as part of my project on food and health perceptions. Several of my respondents happened to be lawyers.. One of the topics under discussion was GMOs (genetically modified organisms). The non-GMO stickers have been put on foods in the country since at least 2013 Screen Shot 2016-08-12 at 1.34.56 PMwhen I visited last. Anything from foods to chewing gum to water bottles boasted the round green NO GMO sticker. Most people I discussed it with actually acknowledged it was simple marketing and didn’t place much trust in the stickers anyway..

So when this July my interviewees mentioned that “well, you HAVE to have the non-GMO label in Ukraine”, I thought they meant that brands just needs to keep up with the competition in hopes of selling more of their product under the illusion of naturalness and purity (big deal for Ukrainians, who still live with the Chernobyl accident of 86, and still worry about environmental pollution in foods).

Well, No- i was told. Ukraine in fact passed an actual law somewhat recently forbidding the import, export, production, or sale of foods with any GMOs. So if you want to place a product on the shelves of Ukrainian stores, they simply have to be certified non-GMO.Screen Shot 2016-08-12 at 12.38.56 PM

Oh! OK… what about reality? In actuality, if you’re placing that product on Ukrainian shelves.. you just pay to get the label put on. Ta-da, it’s non-GMO!

It is all so political, that discussions of population health are mostly for decoration..

Posts like that mentioned above are designed to get you thinking with indignation “I can’t believe my country is so interested in profits!.. they sacrifice our health while other countries actually care about their people’s well being..”. But why do you think Ukraine banned GMOs? It’s to make $ off the new certification and labeling procedures, it’s to look cool in front of Europe (we really want to be accepted to EU, mkay), it’s to keep our image as a serious exporter of quality agricultural products (hey, Ukraine wants to stay the famous breadbasket of Europe! And demand for “clean” or eco agriculture is big. You can’t afford to lose your place in that market)…

It is all so political, that discussions of population health are mostly for decoration (not like absolutely nobody cares, but that’s not the main reason for any of these policies). And of course this is not just Ukraine- I’m just telling you a short specific story. Either way, poor regulatory practices in the country mean that anyone can buy that non-GMO label: nobody’s testing anything and nobody is checking compliance, guys.

Red meat, human vulnerability, and.. mammal pets?

12993520_545709718944195_6669954929821747069_nExciting day! Another diet-related talk at ASU’s Center for Evolution & Medicine. This was a nice break from the horror that is the last 2 weeks of the semester..

It’s taking me awhile to “digest” all the information (hehe), but I found the seminar fascinating and wanted to summarize some main points. Lots of open questions remain, but John Pepper of National Cancer Institute really shows how examination of any health problem needs to focus not only on proximate causes, but the ultimate or evolutionary causes.

So.. Pepper asks- why is mammal meat bad for humans, specifically?

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Meet Dr. Pepper!
In humans, red meat (he refers to it just as mammal meat) is linked to inflammatory diseases (cardiovascular, alzheimer’s, arthritis). What’s the mechanism behind this?
The inflammation from mammal meat has to do with our antibodies attacking something coming from other species.. When we eat mammal meat, we in fact incorporate something non-human from the diet- sialic acid.
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Both human and other mammals have sialic acid in their tissues, actually, but humans have a unique mutation that replaces the form found in other mammals (ancestral form- Neu5Gc) with a different one- uniquely human (Neu5Ac).
So.. if we eat meat we get the new aquired ancestral sialic acid, it becomes part of our cells, and the small structural differences in the two get recognized by the immune system.. which responds with a defense- inflammation!
Chimpanzees are humans’ closest evolutionary relatives, sharing a common ancestor 6–7 million years ago..
WHY does human sialic acid differ uniquely? The “Malaria hypothesis” (see Martin&Rayner, 2005) proposes that in Africa, early humans escaped from the ancestral pathogen they shared with chimpanzees. They managed to do so by replacing the pathogen’s binding target (ancestral sialic acid Neu5Gc) with novel Neu5Ac. With time, a population of that old evaded pathogen evolved to infect humans again by recognizing the new Neu5Ac..leading to the origin of malaria.
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The longer an animal has been domesticated, the more humans share parasites and diseases with them

If the Malaria Hypothesis explains why the initial change in humans happened.. why has it remained the same to this day? I mean, it’s been some several million years now- has this mutation been advantageous this whole time? It’s an important question because this sialic acid mutation poses a COST on our health: this trait causes chronic inflammation in people who eat mammal-derived foods + it also now causes vulnerability to malaria.

The hypothesis for why the human sialic acid modification is still around is that it
provides benefits- specifically, protection from parasites and pathogens via increased inflammation. This is relevant because of what humans have been doing for the last ~15,000 years. Animal domestication!
Humans are more vulnerable to shared pathogens from other mammals (than from non-mammals). So being around cattle, for example, carries a risk of catching pathogens from which that cattle suffers. Such animal pathogens impose a strong selective pressures on humans.. Pepper suggests that the uniquely human sialic acid (Neu5Ac) allows our diet to adapt us to the issue of animal pathogens by adjusting our inflammatory tone (how much inflammation we are experiencing): “those human populations that are exposed to domesticated food-mammals and their pathogens are also eating mammal-derived foods that are pro-inflammatory (both meat and dairy).”
Inflammation is a great example of a trade-off. It both has benefits (protection from parasites & infections) and costs (chronic disease, metabolic expense of mounting an immune response). The optimal balance for this trade-off would depend on how strong of a pathogen pressure you’re experiencing.
This increases inflammatory PROTECTION only where it’s most needed (like around animals). So this auto-immune inflammation from mammal foods in the diet not only increases likelihood of chronic disease, but protects against shared mammalian pathogens.
…..    ……    ……
It got me thinking about human culture and our ability to modify our environment in all sorts of ways- an example of “maladaptation” to modern times! Living in cities, not exposed to higher pathogen load from being around domesticated animals..yet having access to all the mammal meat we can buy = all put you in a situation where the good old sialic acid mutation might do more harm than good. Should people go vegan? Should they simply cut down on red meat? There was no discussion on the effect size of mammal meat eating and chronic disease, so I wouldn’t necessarily jump onto any lifestyle changes based on this talk. Yet the process of understanding this health concern through the lens of evolutionary medicine is quite fascinating!
 P.S. I’m not an expert on this topic. If you have something to correct or add, please comment 🙂
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Very cool use of evolutionary medicine principles in this case & a glimpse into why it’s important to use them if we want to understand disease.

 

Eat Less- Live Long? Not so FAST..

Got it- to FAST? 😀
The past week has been a treat in terms of great talks on campus. At ASU we are super-lucky to have the Center for Evolution & Medicine, which holds weekly talks by amazing speakers.

First
February 18- Arizona State University

When I saw that the upcoming seminar was related to diet and eating..or more specifically NOT eating or “dietary restriction”, I of course RSVPd in a heartbeat.

“Eat breakfast yourself, share dinner with a friend, give the supper to your enemy”- Russian Proverb

I’ve been in fact fascinated with caloric restriction for years now Screen Shot 2016-02-20 at 1.30.46 PM.png(I wrote a whole research paper on it in the first year of my master’s degree). You might have heard of intermittent fasting (e.g. popular in the CrossFit world), or the CR Society ( http://www.crsociety.org/ )- all are related to the concept that restricting food intake results in health benefits (from extending life to preventing and reversing disease).

I’m sure you can Google caloric restriction and find a bunch of information on its reported benefits..you would see this chart at the CR society website- the lifespan of calorie-restricted (CR) mice vs non-CR mice. You can see that those whose food intake was restricted by more & more % lived longer. Screen Shot 2016-02-20 at 1.24.28 PM.pngWhy do many animals (and perhaps humans) appear to be so well-adapted to eating less? The traditional interpretation of this CR phenomenon is that the dietary restriction effect “has evolved as a way to enhance survival & preserve reproduction during periods of naturally occurring food shortage”. In other words- being adapted to do well on restricted food intake during rough times would have helped our ancestors survive them & stay healthy to have kids later when the food situation improves.

The traditional interpretation of this CR phenomenon is that the dietary restriction effect “has evolved as a way to enhance survival & preserve reproduction during periods of naturally occurring food shortage”.

Experimental evidence with animals, however…supports a different hypothesis- the one Dr. Austad (Professor & Chair of the Department of Biology at the University of Alabama) presented to us last week. Again, I wouldn’t be able to cover everything he discussed during the seminar, but I do want to highlight a couple of main points!

I. First, even though the first book on dietary restriction (DR) HowWorks.jpgdates back to the late 16th century, we still do not know the mechanism behind why DR seems to extend life and vigor in animals + delay disease such as cancers. METABOLISM was the original suspect, as metabolic rate goes down with fasting.. however, metabolic rate drops initially yet gradually goes back UP (takes 6-8 weeks to happen).. Since DR changes an unbelievable amount of physiological parameters (see screenshot ->) it is very hard to determine its mechanism.

II. Second, while many sources cite mice experiments showing life extension with caloric restriction.. those experiments are done with lab mice. When DR studies are done with wild mice, DR has no effect on longevity. WHAAAT!! I’ve never heard this before- in fact i was under the impression that CR/DR extends life in animals, period. Well, NO STUDY has ever found that DR extends life or improves health in nature (or even “nature-like” conditions). Mice in the wild actually do not have enough fat stores to reduce feeding except very briefly (wild mice has about 4% fat while a regular lab mice has 15%; also lab mice do not reproduce). In fact, mice in nature simply do not live long enough for the survival benefits of DR to be important. Another challenge to the original hypothesis that adaptation to dietary restriction enhances survival, is that DR increases mortality from some infections. Lastly, DR increases cold sensitivity (and cold is a major source of death in wild mice) and slows down wound healing.

Sounds like animals in the wild would not benefit from adaptation to dietary restriction… yet why is the positive DR effect observed in so many studies so common?

III. Well, even though wild mice do not live longer with restricted diets, DR still results in cancer protection for them. But even more importantly, DR has been found to protect against acute effects of many many toxins! Dr. Austad talks about this discovery in the following way:

 .. if animals can not afford to wait to reproduce..and they have to do it even when food conditions are poor, what they will do is broaden their diet. This means they might be ingesting a lot of toxins they are not normally exposed to (foods infected with fungi, new seed types that are well defended by the chemicals they wouldn’t normally encounter). So the hypothesis is that DR acutely induces broad defense mechanisms from a broad range of toxins

Toxicology studies have shown that mice that are calorically restricted survive a wide range of toxins. DR also acts as an acute (vs. chronic) protectant against other problems (see slide below). Renal ischaemia reperfusion injury (IRI) is a common cause of acute kidney injury and we can see that while ad libitum mice are dying steeply by day 7, those on DR of various proportions survive (30% DR is only 70% of normal food intake; ad libitum stands for eating as much as one wants). This is quite impressive!!!

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These acute benefits of DR have very important implications. We can think about these effects actually protecting the body against the toxins it itself produces (like free radicals).. it also has clinically relevant advantages- e.g. patients on very strong drug cocktails fasting to avoid harsh side-effects. This suggests that the protective effects of DR could have clinical relevance unrelated to chronic benefits like life extension.

The new hypothesis explaining the evolutionary advantage of this paradoxical effect is that dietary restriction arose as a defense against novel exposure to toxins during food shortage.

So in conclusion.. we saw evidence suggesting that dietary restriction would NOT enhance survival in nature. Yet research has shown that DR increases health and life in a diversity of species. The new hypothesis explaining the evolutionary advantage of this paradoxical effect is that dietary restriction arose as a defense against novel exposure to toxins during food shortage.

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My conclusion? I’m still excited about this topic- more than ever before!!! There is a lot of work done now on the timing of food intake as well (not just restricting the amount, but restricting the timing of eating and human health) and I can’t wait to post more about this (after I collect some necessary data though :).  Watch out for early May as I’ll be sharing some more info!

The SciFiles #3: 20 Years Later, Genetically Modified Salmon Approved

I had to write a short, informative, and “unbiased” piece for my work the other month. Posting it here, since it took me a good chunk of the day! 🙂

On November 19th, 2015 the U.S. Food and Drug Administration (FDA) approved the first genetically modified (GM) animal intended for human consumption- AquAdvantage Salmon. The agency reached its decision after 20 years of evaluating research and opinions from a range of sources, including research submitted by the developers themselves (AquaBounty Technologies, a small company in Massachusetts), available peer-reviewed scientific literature, and comments from public hearings and the Veterinary Medicine Advisory Committee. Ultimately, the FDA concluded that the product is safe for humans and animals to eat.

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Both GM and regular Atlantis salmon will end up being the same size, but the GM one will grow FASTER (thus, on the pic, it is larger at the SAME age).

What makes AquAdvantage Salmon unique is that it grows 40% quicker than non-modified farm-raised Atlantic salmon. This effect is achieved by inserting fertilized Atlantic salmon eggs with 1) a growth hormone gene from the Pacific Chinook (or “king”) salmon, and 2) a genetic promoter from an ocean pout fish. This promoter keeps the added gene active all year round, while salmon’s own growth hormone gene is only active in the warmer months. These modifications will not lead to any measurable differences in the GM salmon’s look, taste, or it’s ultimate size and nutrition value, but they will make it grow to adult size quicker.

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Image borrowed from http://www.businessinsider.com/ article by Leslie Baehr

Product Benefits

Clearly, growing almost twice as fast is a considerable economic advantage to fish farmers. In addition, the current practice of catching Wild Atlantic salmon for human consumption is not sustainable as the world’s oceans are already seeing declining fishing yields. Another environmental advantage is a reduced carbon footprint of the fishing industry, as the modified salmon can be grown in captivity close to human populations and reduce transportation costs (in the U.S., 95% of salmon is imported). To the consumer, these factors would potentially result in lower prices and an opportunity to make salmon (a healthy protein choice, according to the U.S. Department of Agriculture) a more affordable part of their diet.

Public Concerns

While the FDA has concluded the GM salmon safe to eat, consumers and public interest groups raise important concerns. One potential issue is the fish escaping into the wild and affecting the environment (e.g. competing with wild salmon for food or mating with it and introducing new hybrid species). The escape scenario, however, is highly unlikely when considering the “multiple and redundant” safety measures in place. First, GM salmon can be raised only in land-based contained tanks in Canada and Panama. Second, there are multiple physical barriers placed in both the tanks and plumbing to prevent the escape of fish and eggs. Lastly, the AquAdvantage salmon is female and sterile, making interbreeding highly unlikely.

In terms of human health implications, Genetically Modified Foods (GMOs) already raise concerns among consumers as people consider possible long-term effects from such a novel technology: 57% of Americans surveyed in 2015 said GMOs were unsafe and 67% stated that scientists do not clearly understand their health effects (Pew Research Center). In contrast, the international non-profit organization AAAS (American Association for the Advancement of Sciences) is more confident about our current state of knowledge, stating that:

the science is quite clear: […] consuming foods containing ingredients derived from GM crops is no riskier than consuming the same foods containing ingredients from crop plants modified by conventional plant improvement techniques”.

(Full statement: AAAS.org) While GM salmon is now approved for sale (though it will take about two years to reach the market), some retailers have already pledged to avoid the product (e.g. Whole Foods, Trader Joe’s) reflecting such consumer worries.

The Labeling Question
One aspect of the FDA ruling saw particular opposition from public groups: GM salmon will not require labeling. While the FDA issued two recommendations for manufacturers to voluntarily label the product, the agency can only require additional labeling if a material difference is present between a GM and non-GM salmon (e.g. differences in nutritional profile). As no such material distinction has been found, a mandatory labeling might incorrectly imply an essential difference between the two.Screen Shot 2015-12-10 at 8.03.09 PM.png

Another issue with requiring labeling is that a “genetically modified” food is not necessary a meaningful category, and the choice of foods to include in it would be quite arbitrary. After all, humans have been modifying the food supply in various ways for quite some time. This includes “wide cross” hybridization resulting in plants not found in nature (including “heirloom” plant varieties often perceived as more “natural”). Another example is radiation and chemical mutagens that are used on seeds to generate new strains (e.g. a Ruby Red grapefruit, which can carry the “organic” label, was created via mutation due to radiation exposure). In comparison to these methods, genetic engineering is arguably the most precise and predictable technique at the moment.

As a consumer, you have a chance to read and comment on the FDA’s proposed guidelines for the industry’s voluntary labeling of GM salmon until January 25, 2016: FDA Regulations

The SciFiles #2: To Fish or Not to Fish?

Is it end of October already??

My ambitious plan to post simple summaries of cool research studies every Friday did no go as planned this Fall. Not only have I traveled internationally to collect data (dissertation, here I come!), but I also have 5 fantastic undergraduate apprenticeship students “working” in my lab this semester. So- a lot of time has been spent on training, learning how to train, and organizing/cleaning/analyzing the data they help collect for my work. 

Nevertheless, it’s time for another post.


Have you heard that fish is healthy for you? That Omega 3s, the “good” fat, is crucial for health? Or have you heard the opposite and are totally confused?

It wouldn’t be a surprise if you were.. Perhaps you’ve seen Screen Shot 2015-10-21 at 4.04.07 PMnews posts like this ->

In my interviews with folks in US and eastern Europe, the conversation includes”healthy fats” quite often. Everybody “knows” fish is healthy and we should all be trying to eat more omega 3 fats that are abundant in fish products for a healthy heart.

Yet in the last several years, many online sources reported on studies that refute these claims.

In this post I’ll briefly summarize a 2014 paper by Grey & Bolland. I believe you can even access it for free by clicking here.

Full reference: Grey, A., & Bolland, M. (2014). Clinical trial evidence and use of fish oil supplements. JAMA internal medicine, 174(3), 460-462.

What Grey & Bolland did was look for the best scientific work on the topic of omega 3 fats and how it affected sales of these supplements. Grey&Bollard summarized18 randomized clinical trials (between 2005 and 2012) that were published in high impact journals (=highest quality journals respected by the scientific community). Randomized clinical trials (RCTs) are considered the gold standard of research and present the highest level of evidence, so if you’re going to look at scientific support for any idea- clinical trials are the way to go!

What did those 18 studies show: well, only 2 studies reported benefits: a 2007 RCT on ~18000 people and using EPA for major coronary events, and a 2005 meta-analysis of RCTs on ~20000 people looking at effect of omega-3 oils and mortality. The other 16- no benefit… Fish oil sales? In the US between 2007 and 2012 fish oil and omega 3 supplements increased from $425 to $1043 million (!). Similar sales pattern were seen in England and Australia+asia. Technically, that’s not logical- if randomized clinical trials are the best and most robust type of scientific evidence, shouldn’t it influence current practices? The authors write:

“Since 10% of adults in the US take an Omega-3 or fish oil supplement, most commonly for heart health or to lower cholesterol, the null results of 9 of the 10 RCTs and 5 of the 6 meta-analyses studying cardiovascular disease  might have been expected to influence use”

I have pulled up the 2005 meta analysis- one of 2 studies from the review that showed benefit to supplementation- to get a bit more detail on the results. Studer et al (2005)* analyzed 97 studies to examine the safety & efficacy of various lipid-lowering interventions using mortality data (= they looked at lipid-lowering supplement/drug use and how often people who took them and didn’t take them die. The separated deaths into 1)either from all causes, 2)cardiac events, and 3) noncardiovascular causes). Such large-scale analysis of these randomized controlled trials is a very important tool- it allows to look at the overall benefit of interventions. This meta-analysis found that two supplements/drugs had reduce risk of overall and cardiac mortality (deaths from all causes and deaths from cardiac events specifically): statins and Omega-3 fatty acids.

Sounds wonderful, but again: it was only 1 of the 2 studies that showed statistically significant benefit of Omega-3s, while the other 16 did not. (statistically significant= meaning something happened Not by chance alone)

* Full reference:Studer, M., Briel, M., Leimenstoll, B., Glass, T. R., & Bucher, H. C. (2005). Effect of different antilipidemic agents and diets on mortality: a systematic review. Archives of Internal Medicine, 165(7), 725-730.


So why do more people continue taking the supplements? Well, first of all, we can assume the public doesn’t read original studies and can be victim to “industry spin”. The “spin” used by industry is a strategy to hype findings and distort the results of clinical studies. Wang et al. (2014) in fact looked this: they analyzed 47 supplements industry press releases & 91 non-industry press releases in response to 46 clinical studies of supplements (published between 2005 & 2013). Result? 100% industry press releases contained “spin” while only 55% of non-industry media pieces did. Industry press releases also reported less on study details – outcome, sample size, effect size- specifically for studies that found no benefit of supplements.

Full citation: Wang, M. T., Gamble, G., Bolland, M. J., & Grey, A. (2014). Press Releases Issued by Supplements Industry Organisations and Non-Industry Organisations in Response to Publication of Clinical Research Findings: A Case-Control Study.

So why else? Well, omega 3 supplements aren’t terribly expensive and people don’t associate them with any RISK, so it makes sense that folks would rather be “on the safe side” and take them. Also, the belief that these fats are “good” can be rather long-term and hard to change- I remember my childhood friends in Ukraine suffering through spoonfuls of fish oil given by their parents. So having a strong long-term belief that fish oils/omega 3s are beneficial can create confirmation bias: looking for evidence that you already agree with and dismissing new research that doesn’t fit your view.

Lastly.. how can fish fat not be beneficial? While I, of course, can not answer that question, here is an interesting piece of theScreen Shot 2015-10-22 at 12.20.39 PM puzzle- genetic adaptation. While I was preparing for a lecture on evolution and human diet, I saw a fascinating research piece at the National Institutes for Health website. Originally, the focus on fish oils came from studies with the Inuit and they seemed very healthy on their traditional fat-rich diets (fat coming from marine sources). So it was thought that fish oil would have a protective effect against cardiovascular disease.. But Dr. Nielsen states:

“We’ve now found that they have unique genetic adaptations to this diet, so you cannot extrapolate from them to other populations”; “A diet that is healthy for the Inuit may not necessarily be good for the rest of us.”

Access full article here.


To supplement or not to supplement, then?
Looks like it is not clear whether dietary supplements with omega 3 fats really influence deaths from cardiovascular causes (strokes, heart attacks) or other causes (cancers) in the population. Yet there is also no evidence that we need to advise people to stop taking these supplements. I suppose it doesn’t hurt..unless it hurts your wallet too much.. Your wallet deserves some good support coming from a good number of randomized controlled trials. 😉

Healthy Eating- Real or Imaginable??

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The lobby of one of the conference hotels during non-busy time. The hallways were overflowing with anthropologists all over the world just hours later 😀

This December I presented on my research at the American Anthropological Association in D.C. (woohoo!) What a blast! The conference was bursting with anthropologists all over the globe; the 5-day event was so packed with presentations that the program which included just names of talks & authors ran about 500 pages.

Anyway, one of the interesting moments from the trip was a scholar (I believe she did some work in Latin America but I don’t know what kind of anthropologist she was), who was seemingly bothered by our session on food and nutrition. Our talks focused on “healthy eating” as a social construct [a social phenomenon created and developed by society; a perception or idea that is ‘constructed’ through cultural or social practice]. My talk was on how perceptions of what healthy eating means differs among and within cultures (Ukrainians & Americans in my study), while other presenters talked about how food is discussed in the Canadian Arctic and among those following a traditional “paleo” diet plan. 

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Presenting on my Ukrainian study!

The question this lady asked was why we spoke of healthy eating as something created and perceived by humans as if there is no objective healthy diet supported by science.

It’s a bit funny to hear someone being surprised that concepts are discussed as a social creation vs. an objective reality at an anthropology meeting.. but that shows how food and healthy eating can be quite emotional when one is health conscious! I would bet this scholar was someone who personally cares about eating well for her own health. Understandable. Food is a very emotional topic- it is not only good/bad for health and looks, it also represents our identity, our culture, our experiences, etc.

Part of my answer to her was that science might not be able to give her what she is looking for- the objective healthy diet. Not because science sucks, but because nutrition studies are lengthy, complicated, and costly (see my post on why nutrition science doesn’t suck HERE). My favorite example of why nutrition science is hard to rely on is SUGAR. Look at this World Health Organization 2003 report (see full report).

The common sense might tell you that added sugar can’t be good- it adds calories, maybe it makes you hungrier or disrupts bodily processes, maybe it’s just unnatural. People I interview often mention that sugar is one of the main causes of weight gain. Common sense, right? Well, look at the WHO report and check out Free Sugars (= all monosaccharides and disaccharides added to foods by the manufacturer, cook or consumer, plus sugars naturally present in honey, syrups and fruit juices). The only convincing evidence from scientific studies is that free sugars increase the risk of dental caries. Not weight gain, not diabetes, not heart disease. Does this mean sugar is only bad for teeth? No, it means there isn’t evidence that it causes other disease with the studies that we have. So if you want to state with complete confidence that added sugars lead to chronic disease and obesity, you might have a hard time backing it up.

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Thinking that there is no such thing as a healthy diet is unsettling. We want clarity. :S Saying that “healthy eating” is an idea constructed socially, however, doesn’t mean that there is no such thing as healthy eating. It does mean that there are multiple ways one can eat well to avoid disease- it can be vegetarian, vegan, paleo, regular calorie restricted diet, Mediterranean diet, etc. etc. etc.

Historical perspective on what good/healthy eating is.

The official stance on a healthy diet is not purely unbiased either- the political and historical context shapes what is officially recognized.  I heard a very interesting talk on the differences in nutrition perceptions between Denmark and Germany during 1940-1945 by Dr. Jensen (University of Copenhagen). She talked how in the early 20th century macronutrients, salts, water and ash were believed to be the sole constituents of food.  Then vitamins were discovered resulting in growing scientific interest in identifying new “micronutrients”, a development that altered (diminished) the perceived importance of the macronutrients (protein, fat, carbs).  So as in Denmark micronutrients became the focus, good nutrition became about vegetables- the source of many micronutrients. In Germany, however, a country experiencing hunger during WWII, macronutrients remained as most important considerations in nutrition textbooks (with protein considered the primary element of food- for the satiety and strength it provides, especially for a country at war!). The point is- the scientific (and thus public) perceptions of what good eating means is shaped by societal circumstances.

It all just depends…

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Baklava- a middle-eastern dessert I am absolutely insane about. My friends sometimes wonder how I can study health yet eat something so “unhealthy” as a high sugared dessert. IS it unhealthy? Turkish people love their sweets, yet traveling around Turkey will show you that the population is not plagued by obesity and chronic disease.

Back to whether an objective healthy diet exists or not. If we ignore for a second that people disagree on the details of what one should eat to stay healthy (is carb or fat evil? is animal protein toxic? should you go vegan? avoid gluten like the plague?), most folks at the minimum agree that eating “real” or whole foods is important (or in other words- avoiding or limiting modern processed foods and focusing on the less modified foods). I suppose we could say that this definition of a healthy diet is generally accepted. If we move on from processed vs. whole, though, here are a couple of examples of when something generally healthy might not be good for you or vice versa:

Cabbage! A wonderful plant full of micronutrients (vitamin K! Vitamin C!) that protect one from various diseases; the plant is often stated to have anti-inflammatory and anti-cancerous properties. Awesome. Unless you have hypothyroidism since cabbage is one of the foods that interfere with the thyroid function.

Dairy! Gets a lot of bad rep from the paleo community and others. While recently thought as very important for bone health and what not, there is a lot of talk that we have not evolved to tolerate it quite well and it is thus an unhealthy substance to consume. Our genes are still adapted to the pre-agricultural diet (before ~10,000 yrs ago), as many paleo proponents will argue. Yet there is evidence to challenge the assumption that humans are essentially unchanged since the Paleolithic era. E.g. “recent” evolution of lactase persistence and variation in the number of genes that code for amylase production tied to starch consumption. In other words, mutations have occured that allow many folks to digest and thrive on dairy and grains just fine.

– Phytates. Plants have a lot of great ingredients that generally affect us positively (e.g. vitamins protecting from disease), but it depends.. For example, phytates in grains and nuts are usually viewed as bad for us because they can bind to certain dietary minerals leading to deficiencies (iron, zinc, etc.).. In West Africa, many Hausa plants contain substantial amounts of these phytates (especially in cereals and legumes) but these botanical chelators have a potential malaria-suppressive effect (awesome!!). However, this anti-malarial effect may be antagonized by antioxidants in other foods (e.g. such free radical traps as Vitamins C, E, beta carotene, selenium). Antioxidants is something many of us try to increase in the diet..yet if you are living in malaria-prone regions of the African continent, you might want to concentrate on the opposite dietary strategy- phytate-rich and antioxidant-poor foods.

989898So is there an objectively healthy diet? Generally- all eating is healthy since it is required for survival.. undereating and overeating is not good.. lacking a variety nutrients is not good.. and that’s mostly it. Of course, different things work for people- someone might not tolerate dairy, others might feel miserable on a vegan diet; some thrive on salads others can’t digest raw plants well. If only we could all grasp the wonderful concept of moderation and apply it in our lives without struggle. In fact, it is because self-control is so hard to maintain that we want simplified solutions- a diet plan, a list of “bad” foods to simply avoid, etc.

Happy Holidays– don’t overeat on most days, yet don’t let yourself stress so much about what you’re eating that you are unable to enjoy life! 😉 *grabs a big fat piece of dark chocolate and kicks back*.

Microbiome Vs. Human

If an alien came to Earth and randomly took a gene sample from one of us… they would most likely end up with a microbial, not human gene. Humans are outnumbered: we have 10 times more microbial cells and 100 times more microbial genes than our own. (February 2017 correction: apparently, that 10:1 ratio was based on one sample from the 70s… while actually, the ratio is more 1:1, so a human body has equivalent amounts of microbial and own cells 😉 gut

Today I heard a fantastic talk by Dr. Alcock- a practicing physician and a PhD in evolutionary biology (great combination that more health professionals should/will be getting in the future!). The question he and many other researchers are now asking is: can microbioms manipulate us to behave in their favor? Perhaps we are not autonomous in our eating; perhaps some of our behaviors represent another genetic interest.

The talk included a lot if interesting outcomes from animal studies on the subject, but that is material for a longer post ( by somehow who is more qualified than I). I will simply summarize some interesting points:

  • Microbiota and humans are not enemies- it is a marriage of convenience where the interests of one are also beneficial to the other. The bugs in our gut do need us to stay alive, as it is good for them also. However, microbiota might not always act in the best interest of the host as the interests of two might result in conflict. Even small differences in gene relatedness can result in conflict (pregnant mothers and fetus, for example, share 50% of genes). And there is zero relatedness in humans and bugs in our guts.A cool example of a conflict is mice infected by toxoplasmosis- such mice in fact seek out feline urine and are attracted to it (vs. having an innate aversion in non-infected mice); they thus look for cat urine, increasing the chances of being eaten by a cat and the parasite spreads further. Microbes can manipulate behavior in other ways- the cordyceps fungus causes its hosts (ants) to act completely out of “character” and leave their normal ground habitat to move onto the high leaves, helping the parasite disperse more spores [The Last of Us video game probably has you familiar with this fun fungus!]. Lastly, human organisms harbor known pathogens as well, yet they do not cause us harm (e.g. e-coli); it is interesting that these pathogens do not produce virulent factors when given simple carb solution (sugar!), a nutrient they require and would otherwise need to get aggressive for.FullSizeRender (1)
  • We can surely manipulate our microbioms. The diet we eat has a huge effect on who’s in our guts- a bug profile of a vegetarian and meat eater are quite different (see photo above). There appears to be a witch-hunt for the bacteria that might be responsible for obesity in humans, but this search has been unproductive with the same suspects being either related or completely unrelated to weight gain.What seems to matter most is the diversity of the bacteria, not having a certain type of it. A Mediterranean style diet with high fiber, for example, produces a more diverse gut environment, while a fast food diet creates a limited one. Some other determinants of a diverse vs. limited environment are on the slide below.  Key Point: Low diversity= Bad health outcomes. Some non-dietary ways to ensure a healthy diverse gut population are probiotics intake (and decreasing antibiotic use), vaginal birth, and breastfeeding; Babies not born vaginally in fact acquire a less complex microbiota that harbors more pathogens.FullSizeRender
  • Can microbioms manipulate…us?? That is the question. Can the gut bugs make us behave differently? Can they make us eat badly and become overweight? While we shouldn’t assume anything for humans yet, there are some examples of potential mechanisms through which bacteria could have an effect on the host.
    • Bacteria has been shown to produce hormones (some are important in stimulating appetite) and neurotransmitters (e.g. serononin that makes us feel good). We need to ask though- do these things pass from the gut to the brain and are actually successful in influencing us? The human body does fight these hormones and neurotransmitters by producing enzymes and antibodies that degrade them and prevent them from crossing barriers (another mechanisms is encapsulating the gut in fat, which also protects the body from escaped bacteria “signals”). It is interesting to note that the microbes might have evolved the ability to produce these things before humans did (as environmental microbes do this too, not only ones that inhabit us), thus they are not primarily meant to affect us.

In conclusion, what we can take out of this knowledge is that we need to encourage people to have high diversity of bacteria in their gut! A whole food diverse diet is a great way to do so, for example. Should we blame our gut bacteria for making us eat junk? Probably not. We can’t pin the blame for obesity and other chronic conditions on a particular microbe, though an overgrowth of one specific group in the gut might be a conceivable issue with their signals interfering with the bodily signals (e.g. in terms of how to eat via hormones and neurotransmitters).

There is so much more fascinating material to cover on the subject but that is for a later date! Lastly, an interesting question was asked in the audience- obese individuals in fact have a low diversity of bacteria… would unhealthy weight gain then be a bad thing for the microbes? Wouldn’t it be a “win” for the human and loose for the bacteria? Interesting question to test 🙂

All material was obtained by a lecture “Allies or Enemies? Gut micribiota & the war on fat” by Dr. Joe Alcock, MD. 2014.

Online Health Wars: Science vs. Public

Since my research includes asking questions about why people think what they do about health, I spent a lot of time reading various discussion boards and comment sections on different health topics. In the last several days I’ve had such an overload of insane online discussions about vaccines, GMOs, and diets that I almost want to quit… 10559827_1659644964260681_5735123775899498101_nAnd yet the often entertaining arguments keep me coming back! The science folks vs. lay folks debates are also interesting since I am myself an ex anti-science alternative health believer who has now “switched sides” on many issues (or as I prefer/hope to think: turned much more moderate in my views based on understanding scientific evidence better).

Have you ever seen a conversation between a “concerned mom/dad who follow their gut” and a “science proponent with experience in the lab” discussing vaccinations? It is sad and funny as you see things like these:

– science person providing links to peer-reviewed literature (really just abstracts, folks can’t access the full text most of the time), questioning parent’s credentials, attempting to explain herd immunity, claiming they lack understanding of science and suggesting to take an into to epidemiology course, blaming them for increasing rates of preventable disease…and as last resorting to calling them stupid, biased, etc.

concerned parent shares links to blogs and anti-vaccine websites, calls the science person’s degree “useless”, emphasizes their credentials as a parent who “just knows” and does their research (via blogs and specific sites), and very often attacks the science guy/girl as being paid by Monsanto or FDA, being dogmatic and inflexible as their degree was provided by corrupt institutions, being stupid, etc.

10420359_1508161656068484_512410907058098671_nNobody ever appears to switch sides, understand where the other person is coming from, or take their evidence seriously. The process of reading such conversations is often sadly hilarious yet less often informative. But most importantly it shows people’s biases.

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