American Society For Nutrition

Interview with Dr. Robert Kushner

ASN is very pleased to present Advances and Controversies in Clinical Nutrition, a conference to be held June 22-24 in Chicago. The conference is designed to keep health care professionals up-to-date on research advances and the most pressing controversies in nutrition. Early registration for the conference is available through April 2 and the call for abstracts has been issued. More information on the program can be found at the webpage.

Organized by the ASN Medical Nutrition Council (MNC), this conference is the result of many hours of hard work by ASN staff and the planning committee. Recently we spoke with one of the members of the planning committee, Robert F. Kushner, MD, Professor of Medicine at Northwestern University Feinberg School of Medicine.

Read the entire interview with Dr. Kushner.

Call for ASN Bloggers Closes Jan. 11, 2012

Student Blogger Program Overview

The American Society for Nutrition blog (www.nutrition.org/asn-blog/) is an integral part of the Society's web presence and an important vehicle to reach members, web visitors, and other interested individuals. To promote the ASN blog as a dynamic communication tool, the Society periodically enlists a cadre of students and young professionals to serve as ASN bloggers and increase posts, comments and activity. The student blogging program increases the visibility of ASN in web search results and among the nutrition education community as a resource for commentary and insight.

Student bloggers are required to submit a minimum of four posts throughout their terms; for these mandatory submissions, bloggers will receive an honorarium of $50 per post. Bloggers can submit additional articles, with a maximum of twelve blog entries posted during their tenures. Students should choose topics that will be of interest to fellow students, as well as other ASN members, consumers, etc.Examples include: hot topics in nutrition (i.e. diabetes, obesity), nutrition programs, experience with nutrition internships, lab research, journal article reviews, postdoc experiences, etc. ASN reserves the right to edit submissions for length, appropriateness and accuracy.

Download the 2012-13 blog application.

Former student bloggers include:

• Umang Agarwal
• Emily Carlson
  
• Lenis Chen
• Jonathan Clinthorne
• Jovana Kaludjerovic
• Alison Kamil
• Rebecca Kanter
• Eric Karlsson
• Rachel Kopec
• Caitlin Leff
• Ann Liu
• Gopi Mara-Koosham
• Harini Sampath
• Mitch Seymour
• Laura Smith
• Bobban Sudhadra
• Matt Thorpe
• Krystle Zuniga

A Talk With SPC Chair Doug Burrin

ASN is in full preparation mode for the Society's Scientific Sessions & Annual Meeting at Experimental Biology (EB) 2012, which will be held April 21-25 in San Diego.  At the center of that planning process is the Scientific Programs Committee and Chairman Dr. Doug Burrin.  Dr. Burrin is a professor at the USDA Children's Nutrition Research Center and also the director of Fellowship Research Training in Gastroenterology, Hepatology, and Nutrition Department of Pediatrics at the Baylor College of Medicine. In a recent interview, Dr. Burrin shared details about the upcoming meeting's most exciting sessions as well as insight from his own experience with ASN and EB. Read the full interview now.

Research Before Acceptance

By Katie O.
ASN Marketing and Membership Intern

I am interning at ASN in the Membership and Marketing Department for the Fall semester and my nutrition knowledge has grown immensely! I graduated in June 2011 from the Ohio State University with my Bachelor's of Science in Human Ecology- Dietetics.  As an undergraduate, I had the opportunity to be involved with many professors' research projects. It was through these experiences that I developed my passion for research and learned the importance of relying on credible sources for information.

You can't believe everything you hear on shows like The Doctors or Dr. Oz. Even though the majority of  Americans may believe these are credible sources for information, being a nutrition professional, I know to maintain a healthy skepticism. Dr. Mehmet Oz has recently come under scrutiny about his “investigation” of arsenic in apple juice. He is claiming that 60% of apple juice is imported from other countries like China where pesticides like arsenic are not regulated.  Of the ten samples, all test positive for arsenic. Some were above the EPA's limit on arsenic in drinking water, which is 10 parts per billion. As an avid apple juice drinker, I began to research the topic. The FDA responded and reassured consumers in a letter that apple juice is safe to drink. They said that the arsenic found in apple juice is due to human activity and is an organic form that is harmless . The FDA has been testing juices for about six years since more products started being imported from other countries.

After reading both sides of the story, I had a few unanswered questions: What is organic arsenic? How does it form? What are the harmful effects of arsenic? Should I be concerned about this in other foods? I did some research through the Argonne National Laboratory and found that organic arsenic is found in many plants, animals and soils. The most common animal that it is found in is shrimp! Many organisms including fungi, bacteria and plants convert the inorganic form of arsenic to the organic form. The organic form is not often toxic unless consumed at extremely high levels. Inorganic arsenic is the most toxic and 80-90% is usually absorbed by the body through the gastrointestinal tract. So I came to the conclusion that apple juice is safe to drink in moderation.    

In my exploration of this topic I also found ASN's scholarly journals to be a fantastic source for nutrition research.  ASN also has official spokespeople who are able to quickly answer nutrition questions with accurate, science-based information. I encourage you to turn to ASN when you need the facts without the hype. Discover all of the spokespeople on the website.

From this news story I learned  to question what you hear on TV. Many times you only hear one side of the story. By doing a little research and turning to reliable experts, you can make sure that you and your patients are properly informed.

Links to resources:
Link to Dr. Oz's test results: http://www.doctoroz.com/videos/dr-oz-investigates-arsenic-apple-juice
FDA's Response Letter: http://www.fda.gov/forconsumers/consumerupdates/ucm271394.htm
Arsenic Fact Sheet: http://www.ead.anl.gov/pub/doc/arsenic.pdf

Beetroot Juice: New Sports Drink?

By Jon C.

It is widely accepted that increased intake of the preservative sodium nitrite found in processed meats such as deli meats, bacon, and hot dogs is associated with negative health outcomes for certain subgroups of the population (1).  These associations have resulted in dietary nitrates and nitrites receiving a “bad name.”  However, scientists have been quick to point out that diets proven to be beneficial for cardiovascular health contain high amounts of fruits and vegetables, are low in sodium and contain polyphenols, potassium, fiber, and, you guessed it, nitrate! (2)  If dietary nitrates and its reduced form, nitrite, are so harmful, then why do we encourage consumption of fruits and vegetables containing these compounds?

Interestingly, dietary nitrate can reduce blood pressure through conversion to nitric oxide resulting in increased vasodilatation (3).  Thus, it stands to reason that enhanced nitrate intake contributes to the cardioprotective effect of dark green leafy vegetables, which are a particularly rich source of nitrate (2).  Evidence is emerging that consumption of dietary nitrate not only has positive effects on blood pressure, but that it also has the ability to enhance some parameters of exercise performance!(3)

In a recent study, subjects consuming 0.5L of beetroot juice prior to exercise exhibited a reduction in systolic blood pressure, as well as decreased oxygen consumption during walking and running (4). Indeed, beetroot juice is a rich source of dietary nitrate as well as other metabolically active compounds including antioxidants and polyphenols. In order to control for these variables, the authors of this study removed nitrate from the beetroot juice to use as a control. It became apparent that the positive effects on exercise observed in this study were due to the nitrate content of beetroot juice. Importantly, results from this study as well as others indicate dietary nitrate increased time to exhaustion in constant speed severe intensity running and cycling as well as decreasing the oxygen cost of exercise, indicating improved exercise economy (3, 5).  While the mechanisms by which dietary nitrate improves these parameters remains to be fully understood, by use of a nitrate free beetroot juice, the authors definitively show that dietary nitrate has a positive physiological response to exercise.

These studies provide a valuable dietary modification of exercise performance. By reducing the oxygen cost at moderate and severe intensity running, one is reducing the energy cost of running.  According to the authors, 4 days of dietary nitrate supplementation induced improvements equivalent to those observed following 6-9 weeks of physical training (4).  Ideally enhanced running economy translates to enhanced endurance; however this parameter was not assessed during this study. Maybe before my next run, I will give beetroot juice a try!

Works Cited

1.    Gilchrist M, Winyard PG, Benjamin N. Dietary nitrate--good or bad? Nitric Oxide.  Feb 15;22:104-9.
2.    Hord NG, Tang Y, Bryan NS. Food sources of nitrates and nitrites: the physiologic context for potential health benefits. Am J Clin Nutr. 2009 Jul;90:1-10.
3.    Ferreira LF, Behnke BJ. A toast to health and performance! Beetroot juice lowers blood pressure and the O2 cost of exercise. J Appl Physiol.  Mar;110:585-6.
4.    Lansley KE, Winyard PG, Fulford J, Vanhatalo A, Bailey SJ, Blackwell JR, DiMenna FJ, Gilchrist M, Benjamin N, Jones AM. Dietary nitrate supplementation reduces the O2 cost of walking and running: a placebo-controlled study. J Appl Physiol.  Mar;110:591-600.
5.    Bailey SJ, Winyard P, Vanhatalo A, Blackwell JR, Dimenna FJ, Wilkerson DP, Tarr J, Benjamin N, Jones AM. Dietary nitrate supplementation reduces the O2 cost of low-intensity exercise and enhances tolerance to high-intensity exercise in humans. J Appl Physiol. 2009 Oct;107:1144-55.

Fasting Metabolism

By Umang A.

Fasting as a political tool has been used since a long time and was popularized by Mahatma Gandhi whose longest fasts went up to a period of three weeks. Since then it continues to inspire many activists throughout the world, one of the famous being Kieran Doherty's hunger-strike in Northern Ireland which lasted 73 days!

So, how long can a person stay alive with only water and no food?

A general estimate for a normal healthy male would be about 35-40 days, however there have been no controlled studies in this direction due to obvious ethical reasons. The survival would of course largely vary between individuals, depending on their genetic makeup, body condition, age and other factors. Females could survive much longer than males owing to a higher fat to protein ratio (since fats are more calorie dense than proteins). When the body is depleted of exogenous nutrients, it starts mobilizing the fat and protein stores to meet maintenance energy needs. Calorically speaking, a person could survive as long as all the fat and protein reserves last, however once the micronutrients such as vitamins become limiting, survival is compromised.

Exogenous glucose lasts for up to 5 hrs once fasting has commenced. Once all the glucose is depleted, the energy needs of metabolism are met by glucose derived from glycogen stored in the liver and muscle. Glucose from glycogen can serve as a dominant energy source for up to 1 d, after which renal and hepatic gluconeogenesis from adipose fat and muscle protein start taking over.

The liver converts fats into ketone bodies, mainly β-hydroxy butyrate and acetoacetate, a process called ketosis. The capability of long-term survival in humans really depends on the adaptability of human brain to utilize these ketone bodies as the main energy source. The glycerol produced on release of free fatty acids can directly be used for gluconeogenesis.

After two days of starvation, about 60% of the glucose is supplied by liver. The main sources for glucose synthesis in liver are alanine from muscle, glycerol from lipolysis and recycled lactate and pyruvate. The remaining 40% of glucose needs is met by the kidney using glycerol from adipose and glutamine from muscle. A prolonged starvation might be fatal mainly due to organ failure, as is the case in anorexia.

Ancient medicinal systems like Ayurveda recommend short term fasting to detoxify and purge the body of unwanted chemicals. There can also be several physiological benefits from short-term fasting. Large amount of literature is now available to show the significance of calorie restriction in extending life span. Other benefits of fasting could be lower risk of heart diseases and higher insulin sensitivity. Fasting is also used as a spiritual tool to turn one's mind inwards into introspection and self-inquiry, and thus is practiced in many religions. However, there can be various associated side effects like nausea, headaches and muscle aches, and therefore a physician's advice is recommended.

I would like to end with a quote by Mark Twain which says, "A little starvation can really do more for the average sick man than can the best medicines and the best doctors."

__________________________________
References:
http://www.annualreviews.org/doi/pdf/10.1146/annurev.nutr.26.061505.111258
http://www.scientificamerican.com/article.cfm?id=how-long-can-a-person-sur&page=2
http://blogs.plos.org/obesitypanacea/2011/05/13/the-science-of-starvation-how-long-can-humans-survive-without-food-or-water/
Image from:
http://www.freepressjournal.in/tfp_cms/gall_content/2011/8/2011_8$largeimg217_Aug_2011_202432967.jpg

ASN Partners to Bring Attention to Childhood Obesity

By Sarah Ohlhorst, ASN Director of Government Relations

The White House recently issued a proclamation declaring September as National Childhood Obesity Awareness Month. ASN has served as a national partner of National Childhood Obesity Awareness since 2010, along with other organizations including America on the Move, American College of Sports Medicine, and HealthCorps. In July, the American Society for Nutrition (ASN) endorsed a resolution introduced by Representatives Marcia Fudge (D-OH) and Kay Granger (R-TX) re-designating the month of September as Childhood Obesity Awareness Month. Educational efforts and events are taking place throughout the entire month of September to bring national attention to the issue of childhood obesity. For example, Nickelodeon is planning a September 24 Worldwide Day of Play– a “blackout” day with zero television programming!

Obesity rates worldwide have doubled in the last three decades, according to a number of articles recently published in The Lancet as part of an obesity series. Globally, an estimated 170 million children under the age of 18 are overweight or obese. In some countries, this includes more than 25% of all children. In the U.S., approximately 17% (or 12.5 million) of children and adolescents aged 2—19 years are obese. Being overweight or obese as a child increases the risk of developing additional diseases such as heart disease, hypertension, and type 2 diabetes and increases the likelihood of becoming an overweight or obese adult. The hospital costs associated with childhood obesity alone were estimated at $237.6 million in 2005.

ASN supports research to elucidate the etiology of childhood obesity, which is a multifactorial epidemic affecting the majority of Americans. Through translational research, ASN members are working to understand how obesity develops and negatively impacts the health of individuals. With this basic knowledge, they are developing and evaluating strategies to prevent obesity in individuals, to aid and maintain weight loss, and to identify and advocate for environmental and policy changes that best support a healthy weight in the U.S. population.

“ASN has increased our focus on the issue of obesity as its impact becomes more and more widespread, including establishing an Obesity Working Group with members who are leading obesity researchers to develop an obesity platform” said ASN Executive Officer John Courtney, PhD. “It is vital that NIH and USDA receive the funding they need so our scientists can continue their research into childhood obesity, it causes, and how to lessen its negative impact.”

Do your part to support National Childhood Obesity Month – help encourage healthy behaviors like regular exercise and good nutrition in your own city or state this month and throughout the year!

Exergaming for Health

By Krystle Z.

Back in the day (1998 to be exact), Dance Dance Revolution was all the rage, and kids were showing their moves on arcade machines all over the world. DDR was soon made available for home gaming systems so people could bust a move in the privacy of their own homes, which is probably where DDR should be done anyway. Over ten years later, the active video game market has exploded. Wii Fit and Wii Fit Plus were two of the top 5 video games titles sold world-wide in 2009, and last year, Sony Playstation Move and Xbox Kinect joined the active video game market.

I have played my share of Wii Sports and Dance Central for Kinect, so I was curious to find out if my leisure time could actually count as physical activity and provide some health benefits. A Pubmed search for “Wii” will generate over 160 hits and future research in the health benefits of video games will likely be found in a new peer reviewed journal, Games for Health: Research, Development, and Clinical Applications (G4H), that will be released this fall. The growing research has also caught the attention of the American Heart Association, who recently teamed up with Nintendo to host “The Power of Play: Innovation in Getting Active Summit” in January. The summit brought together scientists, health professionals, and video game designers to discuss physiological and psychological benefits of active video games and to identify future directions for the development of new games.

Two recent meta-analyses suggest that active video games can increase the user's heart rate and energy expenditure at levels similar to light to moderate-intensity physical activity and can be counted towards physical activity recommendations (1, 3). A recent survey found that over 65% of people who played active video games reported that they became more physically active; suggesting that active video games may be a gateway for user's to begin other physical activity (2) . Just how many calories can you burn playing video games? The American Council for Exercise funded two studies to find this out. Calorie expenditure was measured in 8 men and 8 women (20-29 years of age) while playing Wii Sports and Wii Fit games. Some of their findings:

Wii Sports Bowling 3.9 kcal/min
Wii Tennis 5.3 kcal/min
Wii Boxing 7.2 kcal/min
Wii Fit Free Run 5.5 kcal/min

Over 50% of adults are not meeting physical activity requirements, but active video games may help reduce that number by providing an alternative to a gym membership (not always affordable) or outdoor activities (limited in the winter or extremely hot summers). Now, if people can't make it out of the house to exercise, at least they can get off of the sofa!

References
1. Peng W, Lin J, Crouse J. Is playing exergames really exercising? A meta-analysis of energy expenditure in active video games. Cyberpsychology, behavior and social networking. 2011.
2. Lieberman D, Chamberlin B, Medina E, Franklin B, Sanner B, Vafiadis D. The power of play: Innovations in getting active summit 2011: A science panel proceedings report from the american heart association. Circulation. 2011;123(21):2507-16. 
3. Guy S, Ratzki Leewing A, Gwadry Sridhar F. Moving beyond the stigma: Systematic review of video games and their potential to combat obesity. International Journal of Hypertension. 2011;2011:179124-Epub 2011 Mar 31.

Green and Lean

Green and Lean: Insects are a Nutritionist's Friend

By Gopi M.

The current global food situation is an ultimate paradox.The West is weighed down by the obesity epidemic while the rest faces the unsettling prospect of food shortage due to world population bursting at its seams. The contrast couldn't be any starker.Quite absurdly, on one hand it seems we are the victims of our own innovation while on the other, the palms are always outstretched and empty.Given the crises, nutritional science has an important role to play and nutritionist from the developed nations must step up efforts to highlight the benefits of incorporating insects in our diet to bring down the bias against them.Intensifying research in this regard, as well as breaking the cultural shackles is therefore needed.While you can, go gather grubs for grub and go green!!

For all their creepy contours and freakish features, insects are a nutritionist's delight. Rich in a vast array of nutrients, insects are comparable to other animal sources of food.A grasshopper has 21 grams of protein, 3.9 grams of carbohydrates and 6.1 grams of fat, while dried caterpillars have 28.2 grams of protein for every 100 grams.Not surprisingly, the widespread use of insects in the diet of our ancestors is exhaustively documented.At present, more than 1000 species of insects are used as food across the tropics and sub-tropics. In these parts of the world, insects are roasted, grilled, boiled, broiled, sauteed, fried to serve up delicacies. Although reports abound regarding the earlier usage of insects as crucial elements of gastronomy in France, Germany, Italy and other European nations, the West has developed and moved on well past entomophagy- to harbor bias against insects as food. While it's a matter of preference, it's worth the attempt to expose the public to the nutritional benefits of insects.

Perhaps the stigma associated with insect consumption has got to do with the phase of human evolution when insects were procured during the hunter-gatherer stage.Ironically, insects, in one form or another, are part of our diet.For example, according to the FDA, an average of 5 whole insects in apple butter and 60 aphids or thrips in frozen broccoli are allowed for every 100 grams. In addition to their nutrient value, insects can improve the quality of biomass. Insects can ingest the inedible metabolic waste and can be used as feed to fish and other mammalian species. It's worth noting that the food conversion efficiency of insects like crickets is superior to the conventional livestock.While the developed nations are ahead of the poorer countries in scientific progress and innovation by several leagues, the dearth of understanding of insects and their cultivation and production can have an adverse impact on a global scale.

Table 1. Common insects and protein content on the basis of dry weight

Ramos-Elorduy (1998)

References:

Ramos-Elorduy, J. 1998. Creepy crawly cuisine: the gourmet guide to edible insects.

Rochester VT, USA, Park Street Press. 150 pp.

Katayama, N. 2008. Entomophagy: A key to space agriculture. Advances in space research, 41: 701-705.

DeFoliart, G.R. 1999. Insects as food: Why the Western attitude is important, Annual Reviews in Entomology, 44: 21-50.

Is fish smelly?

What makes fish smell “fishy”?

By Ann L.

If you have ever caught fresh fish, you know that it doesn't have a particularly strong odor, maybe a hint of ocean or lake water.But sometimes the fish you get from the store can have a pungent “fishy” odor.What causes that smell?

The answer has to do with some interesting physiology unique to sea creatures.Water in the open ocean is about 3% salt by weight, but the optimal levels of dissolved minerals inside an animal cell is less than 1%.In order to maintain fluid balance, ocean creatures must fill their cells with amino acids and amines to counter the saltiness of seawater. Ocean fish tend to rely on trimethylamine oxide (TMAO) for this purpose.

The problem is that when fish are killed, bacteria and fish enzymes convert TMAO into trimethylamine (TMA), which gives off the characteristic “fishy” odor.This smell can be reduced in two ways.TMA on the surface of the fish can be rinsed off with tap water.Treating the fish with acidic ingredients such as lemon, vinegar, or tomato can also cause TMA to bind to water and become less volatile.Thus the odor compounds do not reach the nose.

Freshwater fish generally do not accumulate TMAO because their environment is less salty than their cells.As a result their flesh tends to be milder, and they do not get as “fishy” as ocean fish.However, freshwater fish sometimes suffer from an unpleasant “muddy” aroma.This often occurs in bottom-feeders such as catfish, and is caused by two compounds produced by blue-green algae (geosmin and methylisoborneol).These chemicals concentrate in the skin and dark muscle tissue of the fish.Acidic conditions will cause these compounds to break down, so there is good reason for the inclusion of acidic ingredients in traditional recipes.

Next time you have fish be sure to give it a squeeze of lemon or a splash of vinegar!

Reference: McGee, Harold.On Food and Cooking: The Science and Lore of the Kitchen.New York: Scribner, 2004.