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Successes and Challenges of School Lunch Reform

Suzanne Price
ASN's Executive Officer Dr. John Courtney wrote a guest post for the Altarum Health Policy blog, addressing the highs and the hurdles as new school meal standards went into effect. Despite some successes, many schools systems nationwide have struggled to initially implement the new standards for a variety of reasons or have felt that the rules are too confining. Read the blog post in its entirety.

Research Publishing: A Contrary Scientific Environment?

Student Blogger
By Brett Loman

Now more than ever before, the world of academic science is a competitive place. However, does the current environment promote good research? Could the current system from pipette to publication create an environment that incubates bad science? The pressure is on to produce high quality, impactful data in order to climb the academic pyramid, but why is this becoming the rule rather than the exception?

The obvious first place to point fingers is at the evaporating pool of funding. The NIH, a principal funding source for many of us in the life sciences, experienced a budget cut of 5% equaling $1.55 billion below the previous fiscal year. Concurrently, grant success rates dropped to a historic low of 16.8%. Approximately 10% of all submissions to journals are accepted, with top tier publishing groups such as Nature maintaining rates under 8%. Quality control (a very important part of the publication process) can be attributed to a large chunk of these rejections. However, like all businesses, profit and competition rule and questionable research still makes it through the overloaded and poorly regulated peer review process.

Under a publish or perish credo where deans and provosts often value quantity over quality, how likely is it for researchers to overexaggerate and tweak results? Given human nature, it doesn't seem likely that an Olympic-sized group of inflated egos is going to play nicely in the kiddy pool. Should we then be pointing the fingers at ourselves and taking a good look in the mirror? Are these pressures leading to bad practice, and in turn, potentially misleading publications? In a world where the goal line is productivity and that line keeps inching forward, salami slicing, HARKing, positive result bias, cherry picking, and a whole tidal wave of biases are threatening to wipe out the credibility of science and the people who conduct it. What happened to the pursuit of knowledge being noble and objective? Who is to blame and how do we plug up the leak before it becomes a flood?

Certainly the competition isn't going away anytime soon as the number of investigators continues to grow annually. Personally, it seems like a vicious cycle where every faction needs to take responsibility to amend the issues and hold themselves to higher standards. Passing higher values and standards on to the next generation of budding scientists is crucial.

The ASN symposium at Experimental Biology 2014 in April titled “Unscientific Beliefs about Scientific Topics in Nutrition” brought to light these higher values. It was reassuring to hear Drs. Andrew Brown (UAB) and Mark Cope (Solae) point out that these biases and poor practices were not going unnoticed. More importantly, they offered potential solutions. Dr. Brown discussed the importance of honestly reporting the results of other studies. Even if we dutifully report our results, we can only hope that other scientists do not misconstrue these outcomes or condemn us for them. Dr. Cope echoed a common theme raised throughout the session that accessible study registries and approval databases could help curb some of these unethical practices. The missing component in these talks was the role of current culture in publishing groups, which is why I have mentioned it here. Watch the recorded lectures from this session that struck a chord with me. I invite your personal comments and insights below!

Food Addiction: What Does Science Know?

Student Blogger
By Kevin Klatt @nutrevolve

The concept of food addiction is of particular relevance to field of nutritional sciences. The conversation in popular media describes food addiction as though there is scientific consensus surrounding the topic. However, its lack of inclusion in the DSM-V leaves many evidence-based practitioners skeptical about using this kind of terminology. To understand this disconnect, I reached out to Jennifer Nasser, PhD, RD, to hear a researcher and clinician's perspective on this controversial topic.

Dr. Nasser is an associate professor in the Nutrition Sciences Department at Drexel University's College of Nursing and Health Professions. Her research focuses on the neurobiological aspects of food intake and preference. Her current research uses the non-invasive functional near-infrared spectroscope (fNIR) to measure brain activity under varying nutrient and metabolic conditions.

Q: Documentaries like FedUp, books such as Wheat Belly and seemingly countless articles circulating the internet throw around the term ‘food addiction' as if it's fact. What are your thoughts on the term ‘food addiction'?

A:  The problem with the term “food addiction” is two-fold.  One problem is that it is defined differently by different groups of people interested in the topic, i.e. the lay consumer uses addiction to describe “loss of control” over anything, but especially their favorite foods; the clinician uses the term to couple “loss of control” and feelings about “loss of control” with social and health consequences; and the behavior pharmacologists don't use the term because of its clinical associations, rather they focus on the behavior and neurobiology associated with the five domains that characterize “drug addiction”: 
    Dependence = how difficult to quit
    Withdrawal = presence and severity of symptoms in absence of substance
    Reinforcement = ability to promote use over other substances i.e. “loss of control” over use
    Tolerance = how much is needed to satisfy increasing cravings and level of stable need
    Intoxication = mind altering stupefaction, excitement or euphoria that renders a person unable to act competently.
These domains are all based upon the principle that there is no “natural” satiety system for drug use and no beneficial need for “addictive” drugs.  This brings us to the second and more important problem with the term “food addiction”, namely that there is a built in system meant to control food intake in the body and there is an obligatory need to consume food. Consequently, any determination of “food addiction” must be made while controlling for the contribution of the natural control system and need for food and nutrients.

Q: What is the neurobiological basis of this?

A:  Many neurobiological systems are involved in controlling food intake.  There are different orexigenic and anorexigenic peptides (with brain and gut sources) involved as well as neurotransmitters in the brain that contribute to the desire for food.  Examples: orexigenic peptide- ghrelin, some endogenous opioids and endocannabinoids; anorexigenic peptides- leptin, glp-1, cck, amylin; neurotransmitters- dopamine, serotonin, norepinephrine, acetylcholine, endogenous opioids and endocannabinoids, gaba, glutamate.

Q: Is there a gold standard technique in this research? What lines of evidence will be required to prove/disprove that individuals may struggle with food addiction-related behavior?

A: The DSM-V committee that focused on addiction declined to add “food addiction” as a recognized mental illness stated that there is not definitive evidence for its addiction.  One important piece of missing information is which nutrient(s) form the basis for the addiction. Is there just one “addictive” component to food?  Is the addiction to the social associations surrounding food?  

With respect to a gold standard technique: reinforcement by operant responding is used to determine the relative reinforcing value of drugs and to get them classified for addiction potential. Some people have published food reinforcement studies, myself included.  However, if you compare across these studies you find that some are done when people are fasting and a few are done in the satiated, fed state.  The results vary depending upon the feed status of the participants and there's not agreement yet in the field as to the proper conditions for defining addiction potential of various foods.

Q: I've seen many argue that sugar lights up the same areas of the brain as addictive drugs, and, from this, conclude that it too is addictive. Coming from an evolutionary biology background, it makes sense to me that pleasurable nutrients would show this response in the brain. I'm not sure how the primate tree of life would've fared if they stumbled onto fruit and thought ‘meh'. How do you distinguish between a normal physiological pleasure response to nutrients and addictive behavior?

A: Good point.  As I said above, one way is to compare responses in the fed and fasted state. (See Nasser et al. Obesity 2008 16:1816-1820).

Q: I first heard about loss of control (LOC) eating while reading some nutrigenetic research looking at specific FTO genotypes (rs9939609) and their relationship with this sort of eating behavior. Do you think that certain individuals are more prone to LOC eating?

A: Possibly, in addition to FTO, there's some evidence that there are differences in the dopamine transporter gene and D2 receptor genes that confer more susceptibility towards LOC.

Q: The whole concept of LOC eating seems to narrow in on processed foods. Do you think this behavior is independent of processed food consumption? The focus on just sugar seems to be a bit unscientific. Dosage and context of the whole diet are always factors in nutrition – is there research to show they matter with LOC eating? I know there has been other research on the same FTO SNP associated with LOC episodes that used higher protein intake to alter appetite.

A: The focus on sugar is backed by scientific evidence with respect to sugar being the important reinforcing component even in sugar/fat mixtures (see Naleid et al 2008).  With respect to neurotransmitter release, both sugar and fat have shown dose response in relation to dopamine release. (see papers by Hajnal and Bello). Both of these studies have used rats.

Part of the problem of defining the causative substance still comes down to having an agreement as to whether we're talking about domains/characteristics of “addictive” like behavior or we're saying that “activation” of similar brain regions by food and drugs of abuse constitute “food addiction.”

With respect to protein and appetite, I think that again we need to have agreement that experiments to investigate “food addiction” need to use fed, objective calorically satiated participants.  Protein is a good satiating and satiety promoting macronutrient.  If we agree on a standard physical condition for our participants, we could then look at the relative reinforcing power of various food components with respect to the five domains of “addiction” and get some standardized answers.  From there we can then make a collective decision as to whether the reinforcing and/or other domain characteristics seen under standardized conditions rise to a level of concern that needs to be labeled as food addiction.

Q: The IOM recently convened a panel on food addiction. What were the takeaways from this?
A: The IOM is going to release proceedings from their meeting soon, so I think it's best to wait for the official version of the consensus of the meeting.

Q: If people are interested in this topic, what journals or labs would you specifically recommend following?
A: Journals: Appetite, Physiology and Behavior, AJCN, Biological Psychiatry, Neuroimage, Science to name a few.

There are a lot of people actively working in this field and I don't want to not mention anyone, so I would suggest doing a PubMed search, and also a RePORTER search on the NIH website to find those funded to work in food addiction, LOC eating and binge eating, as well as addiction in general.

Q: What are your caveats to other scientists and clinicians with interpreting this research?

A: I agree with the DSM-V committee that we need to define the component(s) of food that promote addictive behavior.  Additionally I think it's very important to define “addiction”-related factors as those that occur in the fed, satiated state.  Until we satisfy our natural nutrient needs, the concept of addiction is irrelevant.  It's the food intake and accompanying calories that are consumed beyond metabolic need that create the negative health consequences.


Is the New Nordic Diet the optimal food system for health and environmental sustainability?

Student Blogger
By Banaz Al-khalidi

Given the public health burden of lifestyle-related diseases, dietary interventions have been studied widely. Successful dietary approaches, such as the Mediterranean and DASH diets, are often limited by the regional food system and cultural adaptation.

The New Nordic Diet (NND) was developed as part of the Danish multidisciplinary OPUS project (1). The NND was designed by gastronomic, nutritional, and environmental specialists to be a culturally sensitive Nordic diet that is palatable, healthy and environmentally sustainable. The average Danish diet (ADD) tends to be low in fruits and veggies, high in animal foods, sugar products and processed foods. The NND is a predominantly plant-based cuisine comprised of locally grown fruits and veggies in season (more berries, cabbage, root vegetables but less tomato and cucumber), whole grains, rapeseed oil, fish and shellfish, high quality meat but less of it, and more organic produce.
 
The health effects of the NND were compared with the ADD in a cohort of centrally obese adults (2). A “shop model” was used by participants to collect food ad libitum and free of charge. Cooking courses and cookbooks were also provided as part of the study. Despite the ad libitum design, the NND group consumed significantly less energy (- 422 calories/d) than the ADD group and had higher self-evaluated diet satisfaction. Significant weight loss in the NND group was accompanied by greater reductions in anthropometric measures. Aside from weight loss, systolic and diastolic blood pressure, plasma triglyceride, total cholesterol, and VLDL cholesterol were reduced in the NND group. It is also worth noting that CRP (C-reactive protein; inflammatory biomarker) levels decreased in the NND group relative to the ADD group. This is in accordance with previous studies where a plant based diet has been associated with lower levels of inflammatory biomarkers.

Another study evaluated the environmentally sustainable elements of the NND (3). The effects of diet composition, food transportation (local vs imports), and production method (organic vs conventional) were evaluated based on 16 environmental impact categories, including global warming potential, respiratory inorganics, and nature occupation. The socioeconomic impact of choosing NND resulted in 5% reduction in the overall environmental cost of ADD. The reduction in the overall environmental cost increased from 5% to 32% when the effect of NND's high organic content was discounted (note: the overall environmental cost of ADD was equated to €835/person per year). In other words, the greater reductions in the overall environmental costs were mainly driven by reduced meat consumption but higher quality meat consumption (i.e. less beef and more grass-fed lamb) and few imported commodities. Organic produce unfavorably increased environmental cost associated with inefficient land use.

Similar multidisciplinary projects are needed in other parts of the world to develop evidence-based strategies that are specific to each region, where policy makers could make use of evidence-based strategies to improve environmental policies. Adapting a regional based diet has the potential to protect both health and the environment but future research should assess the long-term potential of food-environment studies.

Links:
1.    http://foodoflife.ku.dk/opus/english/about/
2.    http://ajcn.nutrition.org/content/99/1/35.short?rss=1
3.    http://ajcn.nutrition.org/content/99/5/1117.abstract

Highlights from the Micronutrient Forum in Africa

Student Blogger
By Sheela S. Sinharoy, MPH

The 3rd Micronutrient Forum Global Conference took place from June 2-6, 2014 in Addis Ababa, Ethiopia, with approximately 1,000 attendees and more than 80 sessions. Some of my personal highlights were:

•    Lindsay Allen's talk on biomarkers for vitamin B12. Dr. Allen argued that depending on the biomarker used, vitamin B12 deficiency may be more prevalent than iron deficiency.
•    Michael Fenech's presentations on the exposome, especially the impact of nutrient deficiencies on the integrity of DNA. He has found that the DNA damage from folate deficiency is equivalent to the damage from 10 times the allowable annual exposure to ionizing radiation.
•    Daniel Raiten and Bas Kremer's talks on the importance of a systems biology perspective. It's good to be reminded of the need for research on nutrient-nutrient interactions and the role of nutrient “clusters” within biological systems.

The most interesting session, however, was the plenary session on the risks and benefits of iron interventions. Many of us know that iron deficiency is the most common nutritional disorder in the world. It is a major cause of anemia but not always the dominant cause. We also know that the main anemia control strategy worldwide is iron supplementation. However, in cases of anemia that are caused by factors other than iron deficiency, iron supplementation can actually be harmful, exacerbating malaria and increasing pathogenic bacteria in the gut. How, then, to determine whether or not iron supplementation is appropriate?

One possible solution came from Sant-Rayn Pasricha, one of the speakers in the plenary, who presented research on the use of the hormone hepcidin to assess iron status. He and his co-authors found that measurement of plasma hepcidin concentrations is useful for detecting iron deficiency and is more sensitive than ferritin. It is also more practical than the current approach, which involves measurements of ferritin, soluble transferrin receptor, and C-reactive protein to assess iron status.

This is of major importance, especially for those of us who work in developing countries where anemia levels are high. In Dr. Pasricha's sample of children in The Gambia and Tanzania, 61% had anemia, but only 13% had iron deficiency anemia. Under current recommendations, all of the anemic children would be given iron supplementation, even though most of them were not iron deficient. This is not only a poor use of resources but, more importantly, potentially hazardous.

Iron supplementation is normally guided by hemoglobin levels, which measure anemia but not iron deficiency. Is it time to replace hemoglobin testing with hepcidin testing? There is no low-cost assay for hepcidin, so this is not a practical solution in the field just yet. In the meanwhile, it is important to consider the risks of infection and iron overload that can follow from inappropriate supplementation.

The knowledge I obtained at Micronutrient Forum will undoubtedly enrich my work moving forward. As I continue to make my way through articles referenced in various presentations, I am already looking forward to the 4th Micronutrient Forum Global Conference, scheduled for 2016 in Mexico.


ASN President to Focus on International Partnerships, Education

Suzanne Price
ASN is excited to introduce the 2014-15 President, Simin Nikbin Meydani, DVM, PhD. As director of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Dr. Meydani is a respected leader in the field. A long-time member, she has also served as ASN's Vice President and Vice-President Elect, as well as in a wide variety of other important roles.  In the interview (click link), Dr. Meydani discusses her goals for her presidency and her views on the future of the field.

Dr Meydani and JensenDr. Simin Meydani (right) and immediate past president Dr. Gordon Jensen share a fun moment during the symbolic passing of the gavel during the annual meeting in San Diego.

International Congress of Nutrition Featured in Advances in Nutrition

Suzanne Price
The May and September issues of Advances in Nutrition (AN) will feature selected proceedings from the 20th International Congress of Nutrition, held in Granada, Spain in September 2013. The proceedings are being published in supplements to AN; supplement coordinators were Angel Gil, Ibrahim Elmadfa, and Alfredo Martinez.

According to Dr. Gil, “For 2014 we planned a comprehensive Congress under the theme Joining Cultures through Nutrition to promote nutrition and healthy lifestyles to people on a sustainable planet. Hence, the 20th ICN offered a modern and attractive Congress, joining different cultures, traditions, and knowledge with respect to new aspects of nutrition research, development, and innovation around the world.”

The scientific program included 6 plenary lectures, 32 special lectures, 4 debates, 90 parallel symposia, 38 sponsored symposia, and 16 satellite symposia. A special effort was made to ensure the involvement of speakers and participants from all continents and countries, including nutrition and food specialists in research, academia, and industry, as well as policy makers, with a gender balance and applicability for all societies. During the 6-day meeting of the ICN, more than 4,000 delegates and 650 internationally renowned nutrition scientists, researchers, and clinicians from 120 countries were actively engaged in discussions, attended sessions and joined networking events. This year the planning committee was especially pleased with the participation of young investigators and nutrition professionals from developing countries.

The IUNS and the 20th ICN wish to thank the California Walnut Commission and Mead Johnson Nutrition for generously providing educational grants to support the publication and distribution of proceedings from the 20th ICN. The contents of this supplement are solely the responsibility of the authors and do not necessarily represent official views of the IUNS.


ASN Comments on Nutrition Facts Label Update

Suzanne Price
ASN Executive Officer Dr. John Courtney recently provided a guest post for Altarum Institute's Health Policy blog. He discusses FDA's proposed changes to the Nutrition Facts Panel, highlighting how the changes impact public health and hopefully will improve consumer health literacy. Read the guest blog here and tell us what you think about FDA's suggested changes!

Interview with Dr. Teresa Davis, Editor, The Journal of Nutrition

Suzanne Price
While the number of publications devoted to nutrition research has risen sharply in recent years, ASN's journals- The Journal of Nutrition, The American Journal of Clinical Nutrition, and Advances in Nutrition, remain the most trusted sources of rigorous, cutting-edge research in the field. To learn what keeps one of ASN's publications top-ranked, we spoke with JN Editor Teresa A. Davis, PhD, who became Editor on January 1, 2014.  Dr. Davis is a Professor of Pediatrics at the Children's Nutrition Research Center at Baylor College of Medicine and a Past President of ASN. In this interview, she discusses JN's submission process, her goals for the publication, and some exciting changes readers can expect to see in future issues.

Nutrition Notes Daily at EB 2014: Final Issue

Paula Eichenbrenner
The wrap-up edition of Nutrition Notes Daily is now available. This concluding version features a recap of the 100% fruit juice sponsored satellite, a summary of video coverage, and an interview with the Danone International Prize recipient Dr. Gokhan Hotamisligil. Attendees can share their thoughts on the meeting by completing the post-EB survey here.

NND wrap up small.jpg