FY2005 Annual Report:  Human Nutrition National Program (NP107)

The mission of the Human Nutrition Program is to define the role of food and its components in optimizing health throughout the life cycle for all Americans by conducting research of high national priority. This includes studies of food composition, nutrient availability, nutrition monitoring, nutrient requirements of the population, food and lifestyle intervention strategies, and the relationship of intake of specific foods and nutrients with obesity prevention and the maintenance of health. This national research program is led by Drs. Molly Kretsch and David Klurfeld, National Program Leaders for Human Nutrition. Dr. Kretsch is the lead on human interventions and population studies while Dr. Klurfeld is the lead on basic and mechanistic studies.

The Human Nutrition Program currently includes 62 research projects involving 94 scientists at locations throughout the U.S. including the six Human Nutrition Research Centers as well as a number of smaller locations. The net to locations ARS budget for the Human Nutrition Program during FY2005 was $77 million.

The quality of scientific achievement in the Human Nutrition Program was recognized in 2005 by major awards to scientists in our program. Two examples are included. Dr. Robert Russell, Director of the Human Nutrition Research Center on Aging at Tufts University, was the recipient of the 2005 DSM Human Nutrition Award for his pioneering work in retinoid and carotenoid metabolism. DSM is the world’s largest supplier of vitamins, carotenoids and other biochemicals.  Dr. David J. Baer, physiologist with the Beltsville Human Nutrition Research Center, was the recipient of the 1^st Annual Bimbo Pan-American Prize for Nutrition, Science and Food Technology for his research on diet and inflammation. Grupo Bimbo, a multinational food company, and Bimbo Bakeries, USA sponsored the prize. 

Each of the Human Nutrition Research Centers was active in holding meetings during FY2005 that involved local and national participation of scientists and other stakeholders. Subjects included Methionine Metabolism in Neonatal/Infant Nutrition in Houston, TX, Potential for Commercialization of High-Selenium Foods in Grand Forks, ND, and Effects of Soy on Growth and Development in Little Rock, AR.

The following section of the report summarizes a representative number of research results addressing objectives of the current national program action plan.  Publications listed represent some or all of the research.

Selected Accomplishments by Component:

Composition of Foods

Major additions to the USDA’s National Nutrient Database.  ARS scientists in Beltsville, MD released the latest version of the USDA National Nutrient Database for Standard Reference (SR18), the primary source of nutrient composition data for foods eaten in the U.S.  Updates included updated/expanded vitamins E and B12 values as well as data on a variety of foods such as french-fried potatoes, pizza, baked products, baby foods, sweeteners, bottled water, wine & beer, industrial wheat flours, new beef cuts, and USDA commodity ready-to-eat cereals. These data are the foundation for most food and nutrition databases in the U. S and are used for food policy, research and nutrition monitoring. 

Available here

New and easily accessible nutrient database for the general public.  ARS scientists in Beltsville, MD released the “What’s in the Foods You Eat Search Tool” on the World Wide Web.  In contrast to previous nutrient databases, this one contains nutritional information for those foods most frequently eaten by Americans.  Such information aids the consumer in making healthful food choices. 

            Available here

Bioavailability of Nutrients and Food Components

Absorption of healthful pigments from plant foods is limited.  High fruit and vegetable consumption is associated with a reduced risk for cancer and heart disease, presumably due to the healthful components in these foods.  ARS investigators in Beltsville, MD studying the red-purple pigments in specialty carrots found that cooking elevates the absorption of some but not all of these antioxidant pigments and that the body is limited in its ability to absorb these healthful compounds. These findings will help consumers and health professionals plan healthful diets to reduce the risk of chronic disease and avoid unneeded supplementation.

Publication:  Kurilich AC, Clevidence BA, Britz SJ, Simon PW, Novotny JA.  Plasma and urine responses are lower for acylated vs nonacylated anthocyanins from raw and cooked purple carrots. J Agric Food Chem. 2005;53:6537-42.

Nutrition Monitoring

New release of national dietary survey data.  U.S. food and nutrient consumption information from the only nationally representative dietary survey, the “What We Eat in America,” National Health and Nutrition Examination Survey, was released on the Web by ARS researchers in Beltsville, MD.  This information is widely used by government, academia, and private industry and is essential to ensuring the nutritional health of all Americans.

            Available here

New data on adherence to the USDA Food Pyramid recommendations.  The Dietary Guidelines for Americans are translated into USDA Food Guide Pyramid servings to help Americans select a healthful diet. ARS researchers at Beltsville, MD released new data tables summarizing the extent to which Americans adhered with these recommendations, as reported in the “What We Eat in America”, National Health and Nutrition Examination Survey (1999-2002).  This information is fundamental to developing sound nutrition education and food policy programs.

            Available  here    

Nutrient Requirements

Calcium and vitamin D reduce falls by older Americans.  Falls are the largest single cause of injury in older adults aged 65 to 80 years and 90% of falls result in fractures.  In a three year study, ARS scientists in Boston, MA demonstrated that vitamin D₃ plus calcium supplementation, in frequently recommended amounts, lowers the risk of falling for this population.  Broad-based increases in vitamin D and calcium could help lower health care costs as well as improve the quality of life for older Americans.

            Publication: Bischoff-Ferrari HA, Orav JE, Dawson-Hughes B.  Effect of vitamin D3 plus calcium on fall risk in older men and women:  a 3-year randomized controlled trial.  J. Bone Mineral Research 2004;19 (suppl 1):S57.

Small deficiencies over time as bad as severe, short-term deficits.  ARS researchers at Grand Forks, ND reported that rats fed marginally-deficient levels of copper for a long time developed cardiovascular damage similar to that seen in animals fed severely-deficient diets for a short period. These results indicate that not meeting dietary recommendations for long periods by a small percentage may be more harmful than previously believed.

Publication: Li Y, Wang L, Schuschke DA, Zhou Z, Saari JT, Kang YJ.  Marginal dietary copper restriction induces cardiomyopathy in rats. J Nutr. 2005 Sep;135(9):2130-6.

Vitamin K helps reduce osteoarthritis.  ARS scientists in Boston, MA found that men and women with higher dietary and blood levels of vitamin K have fewer osteoarthritic joints and less abnormal calcification compared to those with lower dietary and blood levels.  Ensuring adequate vitamin K intake may potentially reduce this age-related form of arthritis in older men and women. 

Health Promoting Properties of Plant and Animal Foods

Fruit and vegetable consumption lowers risk for metabolic syndrome in young adults.  ARS scientists in Houston, TX found that low fruit and vegetable consumption and high sweetened beverage intake are independently associated with the prevalence of metabolic syndrome in young adults who participated in the Bogalusa Heart Study.  Metabolic syndrome, which is characterized by abdominal obesity and the inability to use insulin efficiently, is believed to be a forerunner of coronary heart disease and type 2 diabetes. 

Publication:  S.Yoo S, T. Nicklas T, T.Baranowski T, I.Zakeri I , S.Yang, S. Srinivasan and G. Berenson Comparison of dietary intakes associated with metabolic syndrome risk factors in young adults: the Bogalusa Heart Study.  Am J Clin Nutr. 2004;80(4):841-8.

Relationship between Diet, Genetics, Lifestyle, and the Prevention of Obesity and Disease

Popular diets have no special effect on metabolism. ARS scientists in Boston, MA tested four popular diets for effectiveness and adherence in 160 overweight and obese subjects for weight loss over one year. The diets were characterized as very low carbohydrate, high protein, very low fat, or balanced low calorie. Weight loss was mainly dependent on dietary compliance and the amount of calorie restriction rather than the type of diet. There was no distinct benefit of high protein or limiting carbohydrates or fats.

Publication: Dansinger ML, Gleason JA, Griffith JL, Selker HP, Schaefer EJ. Comparison of the Atkins, Ornish, Weight Watchers, and Zone diets for weight loss and heart disease risk reduction: a randomized trial. JAMA. 2005 Jan 5;293(1):43-53.

Genetic marker for obesity consistent across populations.   ARS scientists in Boston, MA have for the first time shown that common mutations at a gene called “perilipin” modulate body weight in humans -- and more so in women. This genetic predisposition to obesity has been demonstrated in white Americans randomly selected from the general population as well as in Indians and Malays residing in Singapore.  Identifying people with a predisposition to obesity will help in the tailoring of appropriate strategies for obesity prevention.

Publication: Qi L, Tai ES, Tan CE, Shen H, Chew SK, Greenberg AS, Corella D, Ordovas JM. Intragenic linkage disequilibrium structure of the human perilipin gene (PLIN) and haplotype association with increased obesity risk in a multiethnic Asian population. J Mol Med. 2005 Jun;83(6):448-56.

Soy estrogens affect male hormone pathways.  Compounds in soybeans have beneficial health effects that are due to their chemical similarity to the female hormone, estrogen. The most common form of soy estrogen is called genistein. ARS scientists in Beltsville, MD found that genistein reduces activity of genes that respond to male hormones, as well as genes affected by estrogen, in human prostate cancer cells. This finding could help with better dietary recommendations for health.

Publication: Takahashi Y, Hursting SD, Perkins SN, Wang TC, Wang TT. Genistein affects androgen-responsive genes through both androgen- and estrogen-induced signaling pathways. Mol Carcinog. 2006 Jan;45(1):18-25.

Omega-3 fatty acids and fish reduce the risk for cataracts.   Age-related cataract is a major public health problem for Americans, accounting for more than 1.3 million cataract operations each year at an estimated  cost of about $3.5 billion dollars.  In a 16 year study, ARS scientists in Boston, MA have shown that a higher intake of total fat appears to increase cataract risk but more frequent consumption of long-chain omega-3 fatty acids and fish can reduce the risk.  Dietary prevention of commonly occurring health concerns are a cost-effective and essential way of reducing health care costs in the United States. 

Publication: Lu M, Cho E, Taylor A, Hankinson SE, Willett WC, Jacques PF. Prospective study of dietary fat and risk of cataract extraction among US women. Am J Epidemiol. 2005 May 15;161(10):948-59.

Diets containing unrefined whole grains may lower risk for heart disease.  ARS investigators in Davis, CA found that short-term consumption of a diet containing whole grains, in contrast to one with refined cereals and grains, produced a blood lipoprotein profile in women associated with a lower risk for heart disease.  If substantiated by a long-term feeding trial, this kind of diet could provide an important food-based strategy for reducing cardiovascular risk. 

Mineral in cells differentiates healthy from cancerous prostates.  Zinc is essential to health and needs to get inside cells for it to provide benefits. ARS scientists in Davis, CA have provided the first direct evidence that normal cells accumulate more zinc than cancer cells resulting from differences in the proteins that transport zinc across cell membranes. In addition, these scientists identified the target of selenium in human prostate cells as a protein of as yet unknown function. These findings may improve the basis for dietary recommendations for health maintenance.

Publication: Huang L, Kirschke CP, Zhang Y, Yu YY. The ZIP7 gene (Slc39a7) encodes a zinc transporter involved in zinc homeostasis of the Golgi apparatus. J Biol Chem. 2005 Apr 15;280(15):15456-63.

Health Promoting Intervention Strategies for Targeted Populations

Genetic linkages found for childhood predisposition to obesity in Hispanics.  Scientists at the ARS Center in Houston, TX have found strong genetic contributions to obesity in Hispanic children through linking genes with obesity-related biological outcomes.  Over one thousand children, aged 4 – 19 years, and 600 of their parents were studied in Texas.  This knowledge will help target appropriate obesity prevention programs for Hispanic children.

Publication: Butte NF, Comuzzie AG, Cole SA, Mehta NR, Cai G, Tejero M, Bastarrachea R, Smith EO. Quantitative genetic analysis of the metabolic syndrome in Hispanic children. Pediatr Res. 2005 Dec;58(6):1243-8.