ForumDietary 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or may become quickly outdated, leaving us unsettled about how to make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 agencythe Agricultural
Research Serviceand 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
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 89,
probe the role of calcium in helping us maintain healthy bones and forestall
Research at other specialized ARS labs from coast to coast, and overseas,
provides another vital componentnew 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 researchspanning agriculture from field to forkprovide the knowledge that could give each of us a better chance of leading a healthier, more fulfilling life.
Joseph T. Spence