"Complete" Proteins?
Charles R. Attwood, M.D., F.A.A.P.

ntil recently, animal proteins from meat and dairy products were thought to be necessary in order to obtain what nutritionists called "complete proteins."

Proteins are composed of amino acids, 12 of which are manufactured by the human body. Another 9, called essential amino acids, must he obtained from food. Most animal products, such as meat and dairy products, contain all of the essential amino acids and have been designated as containing complete proteins. Most proteins from vegetables also contain all 9 essential amino acids, but 1 or 2 may be low in a particular food compared with a protein from most animal sources. Beans, however, are rich sources of all essential amino acids.

The old ideas about the necessity of carefully combining vegetables at every meal to ensure the supply of essential amino acids has been totally refuted. Modern nutritionists, after observing populations of strict vegetarians who were healthier and lived longer than meat-eaters, now realize that all essential amino acids may be obtained from a variety of vegetables or grains eaten over a one-to-two-day period. This should be a great relief to you as a parent. Even the variety is not as critical as once thought. Dr. Reed Mangels, nutrition editor of Vegetarian Journal, illustrates this by pointing out that if you decide to eat only six to eight potatoes you would get all the essential amino acids you would need in a single day. Of course, her example was intended only to show that combining food daily is not critical for obtaining essential amino acids; eating only potatoes is not recommended, because a more varied diet assures you of other necessary nutrients.

Meat is not necessary to ensure
a supply of complete proteins.

Less than 70 years ago, more than 40 percent of the protein in the American diet came from grains, bread, and cereal. Currently, only 17 percent comes from these sources, along with another 15 percent from legumes, fruits, and vegetables, while two-thirds is from animal products. This trend, also noted in other industrialized Western countries, has been accompanied by a steady increase in heart-disease and cancer deaths.

Along with this shift to animal sources, the total protein in the diet has become excessive. The average American child's diet contains excessive protein, far exceeding the Recommended Dietary Allowances (RDAs) established by the National Research Council. A 4-year-old needs about 33 grams per day; a 12-year-old, 45 grams; and an adult, 50-65 grams. Children actually consume 50-60 grams and adults up to 100 grams, mostly from meat and dairy products. The rural Chinese adult diet consists of an ideal 55-60 grams, mostly from plant sources.

(excerpt from "Dr. Attwood's Low-Fat Prescription for Kids")

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