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Can the Vegetarian Diet Be Healthy?

Student Blogger
By Meghan Anderson Thomas, MS

I constantly hear:

Omnivores: “Vegetarians just don't look healthy.”
Vegetarians: “ Meat just isn't good for you.” Or “I feel so much better when I'm not eating it”

So who has it right?  Can they both be right and wrong at the same time? I think the answer lies in the motivations behind the eater.  The omnivore may have a point because vegetarianism, like all other diets, has the capacity to be unhealthy.

Essentially, vegetarianism, pescetarianism, veganism, etc. are elimination diets.  Like any elimination diet, they have the potential to lack vital nutrients including certain vitamins that are predominately found in animal products.  According to Sabate, vegetarian diets when compared to meat-based diets are more likely to be deficient in vital nutrients(1).  Similarly, when omnivores (typical American diet) obtain the abundance of their calories from meat and dairy they have less room for the fruit and vegetables that provide them with the other nutrients vegetarians so easily acquire.  Moreover, studies show that the increased risk of cancer and heart disease in meat-based diets may be related to a deficiency in the phytochemicals and other compounds found in plant-based foods, not just the intake of saturated fats and excess calories(2).

Again, the problem lies in the motivation. Vegetarians and omnivores alike that eat for health are much more likely to eat properly. The choice of becoming a vegetarian for health reasons alone may lead the vegetarian in question to a more healthful diet in which they are cognizant of variety and balance. That being said, there are plenty of vegetarians that may be doing it for the wrong reasons or are, like most, uneducated in making the proper nutritional decisions.

The observation that vegetarians are unhealthy may actually be evident. Most will argue that they have been deficient in iron, zinc, calcium and B vitamins since they have eliminated animal products, leading to anemia(2).  Not to mention that most vegetarians are women who are prone to anemia due to menstruation. The fatigue that follows leads to the snowball effect of fatigue, decreased exercise and depression. The point is, diet has a strong influence on health and well-being and it is dangerously easy to eat incorrectly, even if one's intentions may be pure. This is seen in all “types” of eaters alike.

It is important to remember that as a vegetarian, the elimination of a steak may reduce your risk for heart disease, hypertension, atherosclerosis, hyperlipidemia, etc., but it is not a free pass to eat all the junk food you can to make up for it.  The elimination of meat alone is not the ticket to health.  Instead, it seems to be a correlation: the vegetarians motivated by health are also more likely to be cognizant enough to eat right all of the time.  Furthermore, Sabate illustrates that the vegetarian diet is viewed as improving health and limiting disease when compared to the meat-based diet(1).

References
1. Sabate, J. (2003). The contribution of vegetarian diets to health and disease: a paradigm shift? The American Journal of Clinical Nutrition, 78 (3), 502S-507S.
2. Nieman, D. C. (1999). Physical fitness and vegetarian diets: is there a relation? The American Journal of Clinical Nutrition, 70 (3), 570S-575S.




Changes on the Horizon: Redefining Malnutrition Diagnoses in Older Adults

Student Blogger
By Jonelle Agurs, ASN Intern

No one wants to get half a diagnosis from their doctor.

Unfortunately, that's what tends to happen when diagnosing malnutrition in hospitalized adult patients in the United States.  The present criteria for some malnutrition assessments, like the Malnutrition Screening Tool (MST), are under scrutiny because they only evaluate patients on symptoms of starvation, such as unintentional weight loss or poor appetite.  However, new studies postulate that malnutrition should not be limited to food behaviors, but should be expanded to include inflammation resulting from chronic disease.  The body's inflammatory response can intensify the symptoms of starvation, and vice versa; poor eating habits may induce inflammation as well.  The human body does an impeccable job of patching itself up using the inflammatory response, but this process often triggers symptoms strongly associated with malnutrition, such as weight loss.  With approximately half of the U.S. adult population (117 million) suffering from at least one chronic condition, such as coronary heart disease and diabetes, it is no surprise that there is an increasing prevalence of malnutrition cases among hospitalized adult patients.

ASN supports the efforts of many of its partner organizations, such as the American Society for Parenteral and Enteral Nutrition and the Academy of Nutrition and Dietetics, which want to recognize the role of the inflammatory response when diagnosing malnutrition. They have proposed four standard criteria: insufficient energy intake, unintended weight loss, muscle mass and fat loss, and diminished physical function.  These criteria will support a more etiological-based diagnosis of malnutrition; a diagnosis more closely linked to the chronic diseases that cause it.  Misdiagnoses often result in patients being discharged early from hospital care, causing inpatients to return later for health issues made worse by the symptoms of poor nutrition.

The International Classification of Diseases, 10th Revision, or ICD-10, is a coding system under the Affordable Care Act of 2010, scheduled to be implemented after October 1, 2015.  Designed to improve disease management, this revision will include coding using an updated definition of malnutrition.  Absence of a standard screening system for this condition is like installing the proverbial cork in the leaky faucet; diagnoses without a simple malnutrition assessment may “plug” up the issue, but the pressure continues to build, waiting for a more thorough solution.  The expansion of the ICD-10 coding system will provide a part of that solution by enhancing screening accuracy.  With five times more descriptors than its ICD-9 predecessor, ICD-10 coding will include more conditions that could be linked to a range of malnutrition-related issues.

Hospitals across the nation are preparing for the ICD-10 updates, but it is imperative that hospital personnel fully understand how to recognize and diagnose malnutrition to code it properly.  Despite shortages of nursing staff and other trained individuals, quality of patient care must be maintained in order to indicate their risk of malnutrition.  Clinicians must be able to perform comprehensive assessments of the patient's complete medical background, so that, along with the newly-proposed diagnostic construct, every patient will receive comprehensive care that will, ideally, lower the cost of their medical care expenses in the future.

Malnutrition, among other hospital-based nutrition topics will be discussed on Saturday, December 6 during the fourth annual Advances and Controversies in Clinical Nutrition conference. Dr. Gordon Jensen, ASN's immediate past president, will give an address titled “Malnutrition and the Affordable Care Act.” The conference runs December 4-6 at the Gaylord National Resort & Convention Center in National Harbor, MD, and features a dynamic program with topics ranging from dietary supplements to nutrition and cancer. To learn more about this year's conference, please visit the website.

Reference
Jensen, G, Compher, C, Sullivan, D, Mullin, G. (2013). Recognizing Malnutrition in Adults: Definitions and Characteristics, Screening, Assessment, and Team Approach. Journal of Parenteral and Enteral Nutrition, 802-807.


Nutrition Research: Revisiting our Foci

Student Blogger
By Kevin Klatt

A few weeks ago, I had the pleasure of reading Allyson West and Marie Caudill's Research and Practice Innovations paper in the Journal of the Academy of Nutrition and Dietetics, entitled “Applied Choline-Omics: Lessons from Human Metabolic Studies for the Integration of Genomics Research into Nutrition Practice” (1). The publication elegantly describes how integrating metabolomic, transcriptomic and genetic/epigenetic approaches into traditional controlled feeding studies can help refine the Dietary Reference Intakes, and elucidate the mechanisms by which choline and folate contribute to overall health.

Referencing the Nutrition Research Priorities established by the American Society for Nutrition (ASN) in 2013 (2), we can clearly see that the approaches described by West and Caudill fall in line with ASN's thinking on how to advance the field of nutritional sciences. The Nutrition Research Priorities report specifically highlights furthering our understanding of nutrition and health by pursuing –omics research to understand individual responses to nutrients. For me, it was encouraging to see these kinds of advanced techniques and their clinical applications representing the field of research in a major clinical nutrition journal.

Fast-forwarding to this past week, I found myself staring at headlines inflaming the conversation around the newest low-carbohydrate/low-fat research, published in the reputable Annals of Internal Medicine (3). The publication is a randomized trial that ultimately concludes “the low-carbohydrate diet was more effective for weight loss and cardiovascular risk factor reduction than the low-fat diet”. Being in such a high profile journal and funded by the NIH, one would expect this publication to add some significant perspective to our understanding of energy balance and disease progression, two areas also highlighted in the 2013 Nutrition Research Priorities report. Unfortunately, upon reading the paper, one is quickly underwhelmed by the lackluster weight loss over 12 months, the poor accuracy of the dietary recall data, the lack of any information about diet quality, the use of imprecise measurement techniques, and the authors' failure to discuss alternative conclusion, beyond just the low-carbohydrate component of the diet. I have specifically detailed the limitations of this trial elsewhere.

As I finished reading the study, West and Caudill's ‘Choline-omics' paper came to mind, and I couldn't help but feel frustrated: why are we still funding these overly reductionist paradigms of low-carb vs low-fat, when much more integrative and informative approaches are being taken? To quote the 2013 Nutrition Research Priorities report on the topic of energy balance:
“A systems approach is preferable because the standard experimental approach of varying one factor at a time has accomplished little to address the population-wide problem of energy imbalance.”
Yet here we are, still trying (and failing) to vary only one factor, and publishing it in a premier journal for physicians. Is this how we want to represent nutrition research?

I further sat and thought about this trial: even at the outset, given the design, and the quality of the proposed data to be collected, what could this have added to our knowledge of nutrition? The trial states that its goal was to conduct a randomized trial to compare low-carb versus low-fat diets on body weight and CVD risk factors in a diverse population without comorbidities. Beyond the overly reductionist paradigm of low-carb/fat, the study design is questionable in that “neither diet included a specific calorie or energy goal.” Ultimately, the trial tested whether a macronutrient goal, coupled with education and a meal replacement bar would spontaneously lead individuals to lose weight, in a diverse population without comorbid conditions. Not surprisingly, after being sent into an environment with highly palatable, minimally nutritious high carbohydrate/ high calorie foods, the low-carbohydrate group fared better. Is this substantially improving our understanding of nutrition and energy balance? If there's any theme that holds true with weight loss and disease risk reduction, it's that choosing a well-planned, reduced energy diet which an individual can adhere to is most important (4,5,6,7). Given the failure to reach recommended fiber intakes and minimal weight loss seen in this trial, nothing about the previous statement appears to change.

Even worse than the limited information to be gained from this kind of trial is the media reporting and subsequent public response to this research. The public's perception of nutrition recommendations isn't that great, as acknowledged in what I would argue is the most pertinent point of the Nutrition Research Priorities report:
“Perhaps the greatest barrier to advancing the connections between food and health is the variability in individual responses to diet; it is also the origin of public skepticism to acceptance of dietary advice….”
If individual variability spurs public skepticism, we should seek to explain that variability. One only needs to look to the original 1980's Dietary Guidelines for Americans (4) to see that we've known that there is individual variation in weight gain/loss and in biomarker response to diets high/low in fat. Yet here we are, 3 decades later, and we're conducting trials that do nothing to further isolate and understand the factors that contribute to this variation. However, what we are doing is deepening this public skepticism, as history shows us the controversial topic of low-carb vs. low-fat undoubtedly garners a lot of press.

Don't get me wrong, research that attempts to understand individual variation in response to food and nutrients is being done, but, despite being identified as a major priority, it does not appear to be so. It's truly a shame to be in this field and see examples of researchers employing the most cutting edge techniques to answer pressing questions, only to be overshadowed by overly simplistic paradigms that incite more sentiment than they do advance science. It is essential that scientists, and more importantly funding agencies, are aware of the field's established research priorities, so that we can stop asking the uninformative questions that tantalize a public controversy and start generating truly substantial evidence, which fosters public trust in recommendations. These established Nutrition Research Priorities can be found in full here.

References:
1.    http://www.ncbi.nlm.nih.gov/pubmed/24529976
2.    http://www.ncbi.nlm.nih.gov/pubmed/23784071
3.    http://annals.org/article.aspx?articleid=1900694
4.    http://www.health.gov/dietaryguidelines/1980thin.pdf
5.    http://www.nejm.org/doi/full/10.1056/NEJMoa022207
6.    http://www.nejm.org/doi/full/10.1056/NEJMoa0804748
7.    http://jama.jamanetwork.com/article.aspx?articleid=200094
8.    http://www.health.gov/dietaryguidelines/1980thin.pdf




Food Security in Puerto Rico: Vulnerable Food Supply

Student Blogger
By Mayra S. Crespo Bellido

In 1942, Dr. Lydia J. Roberts was asked by Dr. M. L. Wilson of the US Food and Nutrition Board to visit Puerto Rico under the pretenses that “there was a problem in [the island], which ordinarily imported much of its food.” After all, the island only produced 65% of the food the habitants needed, 35% was being imported at the time. Dr. Roberts was assigned to study the food and nutrition situation in order to report back to Washington, DC. Out of her collaboration with the University of Puerto Rico as a visiting professor, a clear picture of the living situation for the islanders during the 1940s was portrayed in her book Patterns of Living in Puerto Rican Families. This classic one-of-a-kind report depicts explicitly the poor health conditions and severe food insecurity in most households, mostly due to lack of educational and monetary resources. During this period infectious diseases were ranked #1 among the most common causes of mortality for all ages.

In the 21st century, a changing landscape of health problems troubles Puerto Rico. Following nutrition transition patterns of developing countries, the leading causes of death of our time are all from complications of chronic conditions associated with the increasing prevalence of obesity in the island. In 2013, 35% of Puerto Ricans living in the island benefited from the Nutrition Assistance Program, and the majority of the population benefits from other programs such as WIC and Child Nutrition Programs. Nonetheless, Puerto Rico deals with serious food security issues as the island produces only 17.65% of the food it consumes, importing 82% from over 10 different countries.

According to the Food and Agriculture Organization (FAO), food security exists when all people, at all times, have physical, social and economic access to sufficient, safe and nutritious food which meets their dietary needs and food preferences for an active and healthy life. The four dimensions of food security as defined by the FAO are: food availability, food access, proper utilization and stability. A recent study established that food security is not distributed equally as people living in rural areas of the island are disproportionately affected unemployment rate, greater proportion of habitants below the poverty level and lower education levels all of which may create barriers to food access and proper utilization. However for the Puerto Rican population it becomes a little more complicated than that.

Dr. Myrna Comas, Puerto Rico Secretary of Agriculture, has made it her lifework to bring awareness of the vulnerability of the food chain supply in Puerto Rico. As stated by Dr. Comas, the high dependence on imported foodstuff, constant decreases in local agricultural production, the fact that there is only one functioning seaport that receives all merchandise imported, the great distances food has to travel to get to the island, and a lack of policy to ensure food security are some of the many reasons the food chain supply to the island is susceptible to external influences. Some identified risk factors that could interfere with the supply of food are: global climate change, food and water contamination, reduction of terrains devoted to agriculture in the island, accidents, and free trade agreements, among others.

Under the direction of Dr. Comas, the Puerto Rico Department of Agriculture has systematically addressed these issues for the past couple of years. Part of this plan to counterattack the risk of having a food crisis includes an educational campaign to bring awareness to the matter of food security, and initiatives to conserve agricultural lands and to promote local agricultural production of staple foods. There is evidently a long way to go until this matter is resolved. Hopefully with increased knowledge and understanding of the repercussions of letting this problem remain unaddressed will encourage the proper authorities to create local and international food policy that avoids an impending food crisis in the island.

References
Rosario-Mejías, M, Dávila-Román, A. (2012). Distribución geográfica de la seguridad alimentaria en Puerto Rico, 2005-2009. CIDE Digital 3(1-2), 109-118.

http://academic.uprm.edu/mcomas/HTMLobj-159/tesis.pdf

http://www.elnuevodia.com/expuestopuertoricoaunacrisisalimentaria-1717099.html

http://puertorico.media.indypgh.org/uploads/2012/01/bolet_n__13_enero_2012.pdf

http://jp.pr.gov/Portal_JP/Portals/0/Publicaciones/PublicacionesHistoricasOnline/Compendio%20de%20Estadisticas%20Sociales%20-%201988-2.pdf

http://www.fao.org/focus/e/obesity/obes2.htm

https://www.cfda.gov/index?s=program&mode=form&tab=core&id=3050f5bc0ed98a93fcc273237e0dd0cd







My Clinical Nutrition Internship: Enhancing Physician Education

Student Blogger
By Hans Chiang

I used to be very picky with my food as a child. My parents tried multiple ways to keep me on a well-balanced diet. My interest in nutrition sparked when my parents persuaded me to eat carrots by claiming “carrots are good for your eyes.” While I did not have the scientific fundamentals and resources to research the biochemical mechanism that validates their claim at that age, I trusted my parents, labelled carrots as “good food” and tried to incorporate them into my food choices. When taking biochemistry in my undergraduate studies, these mysterious interactions between foods and the human body unfolded as I learned the science behind how nutrients actually work. Realizing how dietary intake plays a huge role in disease prevention and treatment, I wanted to advance my nutrition education in medical school so that I can provide relevant nutritional guidance to my patients as a physician.

For this reason, I applied for a position in the Clinical Nutrition Internship Program during the summer after my first year of medical school at Indiana University School of Medicine. The program provided me with valuable experiences; not only did I learn about nutritional science from registered dietitians, I also shadowed physicians of different specialties, observe procedures, and learn how they incorporate nutrition into their fields of practice. On top of the clinical exposure, I reviewed my physiology and biochemistry by participating in literature research with my mentor and writing a research paper on the assessment and dietary modulations of endothelial functions.

I had the opportunity to learn from dietitians who assist different patient populations. I spent time in a diabetes care center, a hospital pulmonary and cardiac rehabilitation unit, a retirement community, a cancer radiation center, the local WIC clinic, a community health clinic, the Volunteers in Medicine clinic of Monroe County, and the University Student Health Center. I was surprised to learn how diets are formulated so differently for each unique population. In addition, I learned to appreciate the communication techniques dietitians use to encourage their patients to follow an optimized diet. As a future physician, I would also be working with a very diverse population and these are all useful techniques I can use in my practice.

Besides learning about nutrition from dietitians, I participated in nutrition support rounds and shadowed physicians in different specialties. I shadowed a gastroenterologist and observed esophagogastroduodenoscopies (EGD), colonoscopies, colon decompressions, and gastric tube insertions. I shadowed a bariatric surgeon and observed lap band, cholecystectomy, and hernia repair procedures. I also spent time with an oncologist, a pediatrician, and an endocrinologist to learn about how weight control plays an immense role in treating cancer patients, infants, teenagers, and diabetic patients.

The Clinical Nutrition Internship Program was a wonderful enhancement to my education in becoming a physician. Besides learning about the various roles nutrition has in the health care field, I also obtained valuable communication skills through observing the interactions between the health care professionals and their patients. Regardless of the specialty I pursue in the future, I will be able to incorporate what I learned through this internship into my practice to provide my patients with the best care and education. I enjoyed the eight weeks of the internship very much and am very grateful to have had this opportunity.

Meet ASN's 2014-15 Bloggers

Suzanne Price
ASN is pleased to announce the following 9 bloggers who will serve one-year terms. ASN bloggers are selected through a competitive application process, and those selected hail from a variety of settings, including doctoral programs, medical schools, and postdoc fellowships. Their professional goals and photos can be found here. Let us know what topics you'd like to see written about.

•    Banaz Al-Khalidi, MSc, Doctoral Student, York University, Canada
•    Meghan Anderson, MS, Student, Medical University of South Carolina
•    Mayra S. Crespo Bellido, Dietetics Intern, University of Puerto Rico-Medical Sciences
•    Debbie Fetter, Doctoral Student, University of California-Davis
•    Kevin Klatt, Doctoral Student, Cornell University
•    Brett Loman, Dietetic Intern and Graduate Student, University of Illinois-Urbana Champaign
•    Marion Roche, PhD, MPH, Technical Adviser, Micronutrient Initiative
•    Sheela Sinharoy, MPH, Doctoral Student, Emory University
•    Tiffanie Stewart, MSc, Doctoral Student, Florida International University


How to Have a Healthy School Year: From Kindergarten to Graduate School

Student Blogger
By Debbie Fetter

Summer is quickly disappearing and school is right around the corner. Or, as the graduate students are thinking, what is summer anymore? Regardless, the beginning of school brings new responsibilities and puts time management skills to the test. One thing that often seems to fall by the wayside is healthy living. With a little bit of planning, this doesn't have to be the case.

The Dietary Guidelines Alliance (DGA) recently released a campaign with a mission of taking charge of diet and overall health, rightfully titled, “It's All About You.”  The campaign emphasizes the key to maintaining a healthy lifestyle is to be realistic, active, balanced, adventurous, and sensible. Under each of these components, the DGA offers helpful tidbits designed to assist with goal setting. So, let's have some fun and relate this resource to the typical graduate student lifestyle. [Keeping in mind, this tool is equally helpful for parents, caregivers, and others seeking to make healthy living easy].

It's All About You Cover.jpg

Be realistic:  Just like how you're probably not going to be able to write your dissertation in a week, you can make small changes over time. Set small goals for yourself, such as walking or biking to campus, packing fruit and vegetables to snack on, or choosing whole grain foods.

Be Active:  As students, we spend way too much time hunched over a desk or staring at a computer screen until our eyes start tearing. Come up with a physical activity goal each week and track your progress using a tool, such as SuperTracker. Schedule workouts, just as you would schedule meetings. Set a reminder every hour to get up and do a short circuit (i.e. jumping jacks, push ups, a lap around the hallway, etc.). Get some much needed socialization with a walking date. The possibilities are endless!

running.jpg

Graduate students surprisingly taking a running break instead of a wine break.

Be Balanced:  Although we rarely feel balanced (hello looming stress levels), we can still find balance with our eating and activity. Figure out how many calories your body needs each day here and use a food and activity tracker, such as MyFitnessPal to effortlessly keep count.

Be Adventurous:  Healthy living should never be boring! Pick up a new vegetable and incorporate it into a meal. Find healthy recipe inspiration in cookbooks or online. Choose a day to prepare food for the week, so you'll have nutritious food on hand. Center meals around vegetables, whole grains, and lean protein sources. Escape from the grind and take a scenic walk or hike. Or, find a brave soul to do acrobatic yoga with you (please don't pick me).

Be Sensible:  Graduate students choose to be in school forever, clearly we're not sensible people. Okay, okay, but we can make sensible food choices by reading the Nutrition Facts Label, cutting back on added sugars, adding flavor with spices, and choosing to cook with unsaturated oils (i.e. olive oil, yum!). I guess we can limit the trips to taco bell too.

As summer comes to a close, we don't have to fear losing our healthy eating habits and behaviors. Now, my biggest fear is the undergraduate students... 

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.