Forum—Dietary Guidelines: Expert Advice for Healthy Eating
|In recent years, the news media have done a great job of providing the latest information on advances in nutrition. Unfortunately, some of that information can be confusing or may become quickly outdated, leaving us unsettled about how to make informed decisions regarding what we eat.
So how can we decide what eating habits are healthy? The federal government provides timely, relevant, and reliable nutrition advice. It's in Nutrition and Your Health: Dietary Guidelines for Americans. The current edition, dated 2000, is available for viewing on the World Wide Web at www.health.gov/dietaryguidelines.
The information in Dietary Guidelines is based on a careful and thorough review of nutrition research reported in journals and other scientific literature. The brief, science-based statements and recommendations in the Dietary Guidelines provide the best available nutrition information pertaining to Americans age 2 or older.
The guidelines are written by members of an advisory committee of scientists who are mostly from outside the federal government. The U.S. Department of Agriculture, through its chief research agency—the Agricultural Research Service—and the U.S. Department of Health and Human Services jointly share responsibility for issuing the Dietary Guidelines every 5 years. They alternate taking the lead role in this assignment.
Federal law mandates that the Dietary Guidelines contain nutritional and dietary information and guidelines for the general public, be based on the preponderance of scientific and medical knowledge at the time of publication, and be promoted by each federal agency in carrying out any federal food, nutrition, or health programs.
Users of the Dietary Guidelines include not only federal agencies but also consumers, policymakers, nutritionists, educators, physicians, public health officials, and the food industry.
Work on the 2005 edition has already begun. Advisory committee members, after conducting an extensive and thorough analysis of nutrition research reported since the previous edition of the Dietary Guidelines, will deliberate over the scientific evidence and then make recommendations.
The guidelines have been issued since 1980. Some recommendations have remained constant, such as the advice to eat a variety of foods and to aim for a healthy weight. Others have changed over time. For example, the current guidelines include stronger recommendations about the need to be physically active. That edition also includes new advice about food safety.
Over time, the tone of the Dietary Guidelines has also changed. Early editions tended to provide advice about what foods or food components to avoid. More recent versions are less rigid in tone and more positive in suggesting foods to eat for optimum health and well-being.
One key source of scientific information that is evaluated for the Dietary Guidelines is research conducted throughout the United States as part of the ARS National Program in Human Nutrition. The research that is carried out under this program takes place mainly, but not entirely, at ARS-supported human nutrition research centers in Beltsville, Maryland; Boston, Massachusetts; Davis, California; Grand Forks, North Dakota; Houston, Texas; and Little Rock, Arkansas. Each of these centers has unique resources, critical for defining the role of specific compounds in providing optimal nutrition. Together, the studies conducted at these centers investigate our changing nutrition needs throughout our lives.
This issue of Agricultural Research highlights several ARS contributions to human nutrition research. Investigations conducted at the ARS Western Human Nutrition Research Center on the relationship between vitamin A and our immune system are highlighted in an article beginning on page 10. Other studies at that research center, described on pages 8–9, probe the role of calcium in helping us maintain healthy bones and forestall osteoporosis.
Research at other specialized ARS labs from coast to coast, and overseas, provides another vital component—new knowledge about how we can sustain production of a bountiful supply of nutritious, safe, and appetizing foods for our growing world. Some of this research is aimed at making tomorrow's foods more nutritious. An article on page 18, for instance, describes ARS studies in Sturgeon Bay, Wisconsin, to develop potatoes richer in calcium. This work is an example of how ARS researchers are not only helping to define the importance of calcium, but also working to increase the level of this essential mineral in familiar foods.
The findings from ARS' laboratory and field research—spanning agriculture from field to fork—provide the knowledge that could give each of us a better chance of leading a healthier, more fulfilling life.
Joseph T. Spence