To help Americans make healthy choices about their diets, the U.S. government regularly issues a set of guiding principles, the Dietary Guidelines for Americans. The guidelines, which are meant for all healthy Americans over two years of age, are intended to assist you in making healthy food and physical activity choices.

These guidelines ensure that American diets will include all essential nutrients while maintaining healthy weights for most people. The ultimate goal of the guidelines is to improve personal health by preventing diseases caused by vitamin and mineral shortages (e.g. anemia and scurvy) or unhealthy food handling (e.g. Salmonella), and preventing or delaying the onset of chronic diseases (e.g. cancer and those related to obesity such as diabetes and heart disease). The guidelines also provide information about the importance of regular physical activity, which is a necessary complement to a healthy diet.

It is easy to get frustrated with what appears to be a constant change in recommendations. The explosion of diet and activity information makes headlines every day in the newspaper and on television. In reality, there has been little change over the years--healthy food choices and being active are the mainstays of most advice issued by the government and by health organizations. What have changed are the details contained within the advice.

The guidelines about weight have changed as the science base expanded. In 1980, the message read to maintain ideal weight. Since ideal weight was not easily defined, the wording was changed, in 1985, to maintain desirable weight. In 1990, it was again changed to maintain a healthy weight. Then in 1995, the guideline wording was expanded and changed to: Balance the food you eat with physical activity. Maintain or improve your weight. In 2000, the single guideline became to: Aim for a healthy weight and be physically active every day. These changes took place because of the expanding knowledge about nutrition, activity and health.

Since scientific knowledge keeps changing, every five years, the U.S. Department of Agriculture and Department of Health and Human Services bring together a committee of scientists and practitioners to review the most recent research in nutrition and physical activity and, if needed, the new Dietary Guidelines are developed.

The Dietary Guidelines are important beyond their usefulness to the general public. They also serve as the basis for the highly publicized Food Guide Pyramid and for policies of federal nutrition programs such as the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), the Child and Adult Care Food Program (CACFP), and the School Lunch program. In addition, the guidelines are an important resource for health care professionals.

In April 2005, the Center for Nutrition Policy and Promotion within the U.S. Department of Agriculture released a companion piece to these guidelines. My Pyramid is a graphic representation of the dietary guidelines, similar to the former food guide pyramid. There are five major food groups: grains, fruits, vegetables, dairy foods, and protein foods. My Pyramid personalizes sensible food choices as well as depicts physical activity.

This latest set of recommendations is based on three themes: A-Aim for Fitness; B-Build a Healthy Base; and C-Choose Sensibly. Nine specific categories of key recommendations then were established and they are linked to these three themes.

• Consume adequate nutrients within energy needs-A. When selecting foods, include a variety of foods and beverages that contain lots of vitamins and minerals. The foods should be chosen in a balanced way from within and among the basic food groups. Consume adequate nutrients within energy needs
• Weight management-A. Calories do count. Small decreases in food intake (energy in) and small increases in physical activity (energy out) go a long way in preventing weight gain.
• Physical activity-A. Being active every day promotes both physical and mental health-- engage in regular physical activity (at least 60-90 minutes most days of the week) and reduce sedentary activities. Activities should include those that achieve fitness as well as flexibility such as cardiovascular conditioning, stretching and resistance exercises, or calisthenics for muscle strength and endurance.
• Foods to encourage-B. Fruits and vegetables, whole grain products, non-fat and low-fat milk and milk products.
• Specifics about fats-B. Choose your fats carefully--limit the amount of saturated fats, cholesterol and trans-fatty acids with most fats coming from sources such as fish, nuts, and vegetable oils. Choose cuts of meats, poultry and other foods that are lower in fat and are prepared with little or no fat.
• Specifics about carbohydrates-B. Pick breads, cereals, fruits, and vegetables that are high in fiber. Use and prepare foods and beverages with little added sugars or caloric sweeteners.
• Specifics about sodium and potassium-B. Use and prepare foods with little salt (sodium chloride) while eating fruits and vegetables, which are high in potassium
• Alcoholic beverages-C. If you drink alcoholic beverages, consume in moderation (up to one drink per day for women and up to two drinks per day for men)
• Food safety-C. Make certain hands, utensils and food surfaces are clean. Keep hot foods hot, cold foods cold.

In order to make the guidelines meaningful, spend some time thinking about how you can incorporate them into your life. Decide what you can do to Aim for Fitness, Build a Healthy Base, and Choose Sensibly.

Madeleine Sigman-Grant, PhD, RD, Professor and Area Extension Specialist, University of Nevada Cooperative Extension

National Agricultural Library, Food and Nutrition Information Center, 10301 Baltimore Ave., Beltsville, MD 20705-2351; www.nutrition.gov

U.S. Department of Health and Human Services, 200 Independence Ave., S.W. Washington, D.C. 20201; 877-696-6775; www.healthierus.gov/dietaryguidelines

Center for Nutrition Policy and Promotion; www.usda.gov/cnpp

U.S. Dept. of Agriculture; www.mypyramid.gov