Where do vitamin, mineral, and fiber supplements fit in? Supplements of vitamins, minerals, or fiber also may help to meet special nutritional needs. However, supplements do not supply all of the nutrients and other substances present in foods that are important to health. Supplements of some nutrients taken regularly in large amounts are harmful. Daily vitamin and mineral supplements at or below the Recommended Dietary Allowances are considered safe, but are usually not needed by people who eat the variety of foods depicted in the Food Guide Pyramid.

Recommended Dietary Allowances (RDAs) represent the amounts of nutrients that are adequate to meet the needs of most healthy people. Although people with average nutrient requirements likely eat adequately at levels below the RDAs, diets that meet RDAs are almost certain to ensure intake of enough essential nutrients by most healthy people. The Dietary Guidelines describe food choices that will help you meet these recommendations. Like the RDAs, the Dietary Guidelines apply to diets consumed over several days and not to single meals or foods.

Sometimes supplements are needed to meet specific nutrient requirements. For example, older people and others with little exposure to sunlight may need a vitamin D supplement. Women of childbearing age may reduce the risk of certain birth defects by consuming folate-rich foods or folic acid supplements. Iron supplements are recommended for pregnant women. However, because foods contain many nutrients and other substances that promote health, the use of supplements cannot substitute for proper food choices.