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Nutrients Proteins Carbohydrates Fats Cholesterol Mineral Elements Vitamins Fiber Water Weight Control

Proteins

Protein is the basic building block of every cell in the body. In addition, protein is used to make blood, form antibodies that fight infection, and supply energy. You need protein in your diet every day. About 15 to 20 percent of your daily calories should come from protein.

Proteins are composed of materials known as amino acids. The body makes some of these, but others, called essential amino acids, must be obtained ready-made from food. The nutrient value of any food protein is determined by the number of essential amino acids it contains. Proteins that supply the most of these compounds are rated highest in biological value, and best meet the body's needs.

The most common sources of "high-quality" protein are meat, fish, poultry, eggs, milk, and dried peas and beans. Unfortunately, many of these sources are also high in fat and cholesterol. However, fish, poultry without the skin, low-fat dairy products, and dried peas and beans provide high-quality protein without too much fat.

No single cereal grain, vegetable, or fruit supplies all the essential amino acids, though each provides some protein. By combining cereal and vegetable foods with a little meat or other source of animal protein, you can improve the protein value of your meal. Examples of such combinations include rice and beans, peanut butter and bread, cereal with milk, rice and fish, and spaghetti with meat sauce.

Vegetarians may have a problem getting enough protein in their diets, particularly if they do not eat either dairy products or eggs. It is difficult to plan a vegetarian diet so that it includes enough of the nutrients that are often scarce in vegetables, such as vitamins and minerals.