GOAL 4: IMPROVE THE NATION’S NUTRITION AND HEALTH
Analysis of Results: This goal is the focus of ARS’ research related to human nutrition and health. Under Goal 4, 6 Indicators are aligned under 3 Performance Measures. As the National Programs evolve, the Agency will report more accomplishments achieved by collaborative research at multiple locations involving more than one scientific discipline. Thus, we anticipate reporting fewer accomplishments, but accomplishments that are broader in scope that make greater contributions to American agriculture. While it is not possible to report research accomplishments numerically, the progress projected in these Indicators was completed or substantially completed during FY 2004. Nineteen significant accomplishments are reported below.
OBJECTIVE 4.1: Promote Healthier Individual Food Choices and Lifestyles and Prevent Obesity; Improve Human Health by Better Understanding the Nutrient Requirements of Individuals and the Nutritional Value of Foods; Determine Food Consumption Patterns of Americans.
Performance Measure 4.1.1: Scientifically assess the efficacy of enhancements to the nutritional value of our food supply and identify, conduct, and support intramural and extramural research to develop, test, and evaluate effective clinical and community dietary intervention strategies and programs for modifying diet, eating behavior, and food choices to improve the nutritional status of targeted populations. A special emphasis is to prevent obesity and promote healthy dietary behaviors.
During FY 2004, ARS will
identify dietary and lifestyle intervention strategies to prevent obesity and promote healthy food choices and eating behaviors.
ACCOMPLISHMENTS: ARS researchers compared weight loss efficacy of four popular diets – Atkins, Zone, Weight Watchers, and Ornish – in 160 overweight and obese adults for 12 months.
IMPACT/OUTCOME: The research indicates there are no special metabolic differences from high protein, low fat, or other composition diets. The results emphasize that adherence to a diet is the most important factor in weight loss, not the amount of fat, protein, or carbohydrate.
ACCOMPLISHMENTS: ARS scientists showed that consumption of a diet containing whole grains, in contrast to one containing refined cereals and grains, elevates satiety and shifts metabolism from using dietary fats to using body fat for energy needs.
IMPACT/OUTCOME: The findings provide new science-based information for developing food-based strategies for preventing unhealthy weight gain in adults.
ACCOMPLISHMENTS: Research demonstrated that men regulate weight primarily through physical activity while women regulate weight primarily by changing their diet.
IMPACT/OUTCOME: Based on the research, public health policy for maintaining a healthy body needs to take into account gender differences in adults.
ACCOMPLISHMENTS: ARS researchers showed that poor rural residents of the Lower Mississippi Delta eat less protein, fruits, vegetables, vitamins, and minerals, but the same calories as the rest of the population and have a higher incidence of obesity and chronic health problems.
IMPACT/OUTCOME: These data show that both diet and physical activity differences are likely to account for obesity and its related complications.
conduct research that enhances the nutritive value of the food supply.
ACCOMPLISHMENTS: Researchers demonstrated in a long-term human feeding study that whole grain barley, rich in soluble fiber, can lower blood cholesterol levels and reduce diastolic blood pressure in adults.
IMPACT/OUTCOME: The barley industry has filed a petition with the Food and Drug Administration for a health claim based upon ARS’ research.
ACCOMPLISHMENTS: Researchers found that strains of beneficial bacteria from yogurt colonize the intestine of pigs and activate their immune system. This had the effect of reducing an allergic reaction to an experimental parasitic infection.
IMPACT/OUTCOME: The findings suggest that healthful bacteria can help prevent infections by disease-causing organisms. This may benefit sales of fermented dairy products that contain cultures of these bacteria.
ACCOMPLISHMENTS: ARS scientists established a dose of cinnamon fed to humans that improves blood glucose and lipids in volunteers with type 2 diabetes.
IMPACT/OUTCOME: Proof of concept establishes that isolation and synthesis of the active factor in cinnamon could be used to treat diabetes. A CRADA partner has been identified and is subsidizing this research. If commercialized, the financial impact is substantial since 12 million Americans have been diagnosed with diabetes and the annual economic burden is more than $132 billion.
Performance Measure 4.1.2: Define functions, bioavailability, interactions, and human requirements (including effects such as genetic, health status, and environmental factors) for known, emerging, and new classes of nutrients. Determine the abundance of known, emerging, and new classes of nutrients in the food supply and provide that information in databases.
During FY 2004, ARS will
determine the functions, bioavailability, interactions, and requirements for known, emerging, and new classes of nutrients across the life cycle.
ACCOMPLISHMENTS: ARS scientists showed that vitamin E supplements given to elderly nursing home residents for one year significantly reduced the incidence of upper respiratory infections.
IMPACT/OUTCOME: Since morbidity and mortality are greatly increased in the elderly following occurrence of common colds, this study has the potential to reduce the severity of illness and attendant medical costs which are often borne by Federal programs for this group.
ACCOMPLISHMENTS: ARS researchers determined the rate of utilization in humans of two carotenoids, lutein and beta-carotene, by feeding isotopically labeled kale. Lutein was much more effectively used than beta-carotene. Bioavailability of carotenoids was also studied using juice from purple carrots developed by ARS.
IMPACT/OUTCOME: These studies inform scientists about how effectively different pigmented carotenoids are used by the human body. It also is important for understanding the bioavailability of plant components and whether increasing these components will make crops nutritionally superior.
ACCOMPLISHMENTS: ARS researchers found that adding meat to the diet favorably influenced blood indicators of bone growth and turnover. Further, amounts of meat commonly consumed by the American population did not increase urinary calcium excretion.
IMPACT/OUTCOME: Older, less well controlled studies had indicated the opposite and meat consumption was sometimes avoided by women because of believed adverse effects on bone health. This study should allay those concerns and benefit sales of meat.
ACCOMPLISHMENTS: ARS scientists demonstrated that chronic high dietary copper levels can alter measures of immunity and oxidative stress.
IMPACT/OUTCOME: New knowledge on the potential health effects of long-term high copper consumption is required in order to refine the newly established upper tolerable level for dietary copper. This information will be used to ensure that the level of copper provided in foods and supplements is safe for the American public.
ACCOMPLISHMENTS: ARS researchers showed that children eating a low calcium diet can only partially adapt to the lower amount by increasing the proportion of dietary calcium absorbed from the intestine.
IMPACT/OUTCOME: Many children are not consuming sufficient dietary calcium and this increases risk of osteoporosis and fractures in later life. This research contributed to the recommendation in the Dietary Guidelines for Americans to consume daily 2 to 3 servings of milk, milk products, or other calcium-rich foods.
develop new methods, conduct food composition analyses, and compile databases for known, emerging, and new classes of nutrients across the life cycle.
ACCOMPLISHMENTS: ARS researchers determined that the folic acid content of fortified cereal grain containing foods is substantially higher than required by law.
IMPACT/OUTCOME: The Food and Drug Administration mandated fortification of refined cereal grains in 1998 to prevent neural tube defects in the babies of mothers not receiving sufficient dietary folic acid during pregnancy. However, the levels actually in the U.S. food supply are considerably higher than intended. This new information points to the need for research on the health implications of high folic acid intakes by the American public.
ACCOMPLISHMENTS: AS scientists developed and released special interest databases for fluoride, choline, and proanthocyanidins which are not part of the USDA National Nutrient Database for Standard Reference.
IMPACT/OUTCOME: Information in these databases is used by industry for fortification purposes (fluoride) or by nutritionists to recommend healthy eating patterns.
ACCOMPLISHMENT: Scientists initiated development of a new procedure to determine six B vitamins in foods and dietary supplements. They evaluated a new method for the analysis of amino acids in foods containing sulfur and selenium. They also developed a new analytical method to separate different forms of iron in meat.
IMPACT/OUTCOME: These improvements in food analysis will allow more accurate information to be collected for dietary surveys and help food processors in knowing the nutrient content of their products.
Performance Measure 4.1.3: Determine food consumption patterns of Americans, including those of different ages, ethnicity, regions, and income levels. Provide sound scientific analyses of the U.S. food consumption information to enhance the effectiveness and management of national and community food and nutrition programs.
During FY 2004, ARS will
survey and analyze national food consumption patterns of Americans.
ACCOMPLISHMENTS: ARS released the “What We Eat in America” dietary intake data for 2001-2002 on the Internet in collaboration with the Department of Health and Human Services. This yearly nationwide survey provides essential information on foods and nutrients in the contemporary American diet.
IMPACT/OUTCOME: This information is critical to understanding the role diet plays in promoting health and reducing obesity and disease throughout life. It is widely used by government agencies, universities, and the food industry for a variety of purposes, such as, establishing dietary recommendations, setting food assistance program policies, and determining if the U.S. food supply requires enrichment or fortification.
ACCOMPLISHMENTS: ARS researchers found that personality characteristics are associated with under-reporting food intake on dietary recall, the key tool used to assess food and nutrient intake in the United States. Individuals with poor body image were more likely to under-report food intake.
IMPACT/OUTCOME: This kind of information helps determine who is likely to misreport dietary intake information. Such information is essential to improving the accuracy of national dietary survey methodology.
develop and test new dietary assessment methods and nutritional status markers.
ACCOMPLISHMENTS: A longitudinal study of 2,000 older adults with 12.5 years follow-up was completed. The study found blood levels of the amino acid homocysteine were a strong, independent predictor of bone fracture in addition to being associated with heart disease.
IMPACT/OUTCOME: Levels of homocysteine are primarily affected by B vitamin status and reflect their intake and utilization. This new information provides the basis for developing food-based strategies to prevent bone fractures in older adults.
ACCOMPLISHMENTS: Food frequency questionnaires (FFQ) are the most cost-effective means for determining dietary intake in studies with large numbers of subjects. New FFQ’s were developed for use in the Southern United States and for Hispanics in the Northeastern United States.
IMPACT/OUTCOME: These new assessment methods will help improve the accuracy and reproducibility of nutrition research studies. They point to the need for different dietary instruments for specific population groups, whether geographic or ethnic.