Foods contain combinations of nutrients and other healthful substances. No single food can supply all nutrients in the amounts you need. For example, oranges provide vitamin C but no vitamin B12; cheese provides vitamin B12 but no vitamin C. To make sure you get all of the nutrients and other substances needed for health, choose the recommended number of daily servings from each of the five major food groups displayed in the Food Guide Pyramid (figure 1).
Americans do choose a wide variety of foods. However, people often choose higher or lower amounts from some food groups than suggested in the Food Guide Pyramid. The Pyramid shows that foods from the grain products group, along with vegetables and fruits, are the basis of healthful diets. Enjoy meals that have rice, pasta, potatoes, or bread at the center of the plate, accompanied by other vegetables and fruit, and lean and low-fat foods from the other groups. Limit fats and sugars added in food preparation and at the table. Compare the recommended number of servings in box 1 with what you usually eat.
See box 2 for suggested serving sizes in the Food Guide Pyramid food groups. Notice that some of the serving sizes are smaller than what you might usually eat. For example, many people eat a cup or more of pasta in a meal, which equals two or more servings. So, it is easy to eat the number of servings recommended.
You can achieve a healthful, nutritious eating pattern with many combinations of foods from the five major food groups. Choosing a variety of foods within and across food groups improves dietary patterns because foods within the same group have different combinations of nutrients and other beneficial substances. For example, some vegetables and fruits are good sources of vitamin C or vitamin A, while others are high in folate; still others are good sources of calcium or iron. Choosing a variety of foods within each group also helps to make your meals more interesting from day to day.
Some Americans eat vegetarian diets for reasons of culture, belief, or health. Most vegetarians eat milk products and eggs, and as a group, these lacto-ovo-vegetarians enjoy excellent health. Vegetarian diets are consistent with the Dietary Guidelines for Americans and can meet Recommended Dietary Allowances for nutrients. You can get enough protein from a vegetarian diet as long as the variety and amounts of foods consumed are adequate. Meat, fish, and poultry are major contributors of iron, zinc, and B vitamins in most American diets, and vegetarians should pay special attention to these nutrients.
Vegans eat only food of plant origin. Because animal products are the only food sources of vitamin B12, vegans must supplement their diets with a source of this vitamin. In addition, vegan diets, particularly those of children, require care to ensure adequacy of vitamin D and calcium, which most Americans obtain from milk products.
Some foods such as grain products, vegetables, and fruits have many nutrients and other healthful substances but are relatively low in calories. Fat and alcohol are high in calories. Foods high in both sugars and fat contain many calories but often are low in vitamins, minerals, or fiber.
People who do not need many calories or who must restrict their food intake need to choose nutrient-rich foods from the five major food groups with special care. They should obtain most of their calories from foods that contain a high proportion of essential nutrients and fiber.
Many women and adolescent girls need to eat more calcium-rich foods to get the calcium needed for healthy bones throughout life. By selecting low fat or fat-free milk products and other low fat calcium sources, they can obtain adequate calcium and keep fat intake from being too high (box 3). Young children, teenage girls, and women of childbearing age should also eat enough iron-rich foods, such as lean meats and whole-grain or enriched white bread, to keep the body's iron stores at adequate levels (box 4).
National policy requires that specified amounts of nutrients be added to enrich some foods. For example, enriched flour and bread contain added thiamin, riboflavin, niacin, and iron; skim milk, lowfat milk, and margarine are usually enriched with vitamin A; and milk is usually enriched with vitamin D. Fortified foods may have one or several nutrients added in extra amounts. The number and quantity of nutrients added vary among products. Fortified foods may be useful for meeting special dietary needs. Read the ingredient list to know which nutrients are added to foods (figure 2). How these foods fit into your total diet will depend on the amounts you eat and the other foods you consume.
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.
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.
Enjoy eating a variety of foods. Get the many nutrients your body needs by choosing among the varied foods you enjoy from these groups: grain products, vegetables, fruits, milk and milk products, protein-rich plant foods (beans, nuts), and protein-rich animal foods (lean meat, poultry, fish, and eggs). Remember to choose lean and low fat foods and beverages most often. Many foods you eat contain servings from more than one food group. For example, soups and stews may contain meat, beans, noodles, and vegetables.