National Nutrition Month occurs annually during the month of March, but it focuses on personal health habits that should be practiced for a lifetime.

The American Dietetic Association has sponsored National Nutrition Month since 1973. Each year the association encourages consumers to eat better and to exercise more frequently to improve or maintain a healthy lifestyle.

The ADA says variety, balance and moderation are the three keys to healthy eating. The Food Guide Pyramid is based on these keys.

No one food group can supply all the nutrients a body needs. It is important to eat a variety of foods from several of the food groups so that you will meet your nutrition needs each day.

"Most Americans eat way too much food," says Dr. Barbara Struempler, nutritionist at the Alabama Cooperative Extension System. The average portion size for most people equals two or three servings at each meal instead of the recommended serving size by the ADA's Food Guide Pyramid.

Appropriate portion sizes range from ¹/3 to one cup, depending on the food and sometimes how it is cooked. If you don't have a measuring cup to measure the food, use these tips as a quick reference:

• Three ounces (one serving) of meat, poultry or fish is about the size of a deck of playing cards or the palm of a woman's hand.

• One serving (one ounce) of cheese is equal to one thin slice of prepackaged cheese or a chunk about the size of your thumb.

• One serving of chopped green salad is a small handful of greens.