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Getting complete Protein

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Getting Complete Protein
Nutritionists use the phrases "complete protein" and "incomplete protein" to describe the proteins provided by various foods. If a food supplies a sufficient amount of the nine essential amino acids, it is called a complete protein. Virtually all proteins from animal foods are complete. Foods that lack or are short on one or more of the essential amino acids - such as some fruits, grains, and vegetables - are called incomplete proteins.

Such plant-derived foods can nonetheless be excellent sources of protein if eaten in combinations that supply all of the essential amino acids. For example, the amino acids missing in a vegetable can be provided by eating a grain product, another vegetable, or an animal-derived protein at the same meal.

Animal vs. vegetable
Meat and other animal products are the most readily available sources of complete protein. The protein content, by weight, of cooked meat, fish, poultry, and mild solids is between 15 and 40 percent. The protein content of cooked cereals, beans, lentils and peas ranges from 3 to 10 percent.

Potatoes, fruits, and leafy green vegetables come in at 3 percent or lower. Soybeans and nuts have a protein content comparable to meat, but, depending upon how they are prepared, their proteins may not be as easily digested. However, recent research suggests that in a mixed or even totally vegetarian diet, the issue of digestibility is not too important. For someone eating a whole grain and vegetable diet, no more than 15 percent of the protein consumed would be unavailable because of problems with digestibility.

The fact that we are omnivorous, that is, we can eat both meats and plants, has contributed to the survival of the human species. But as anthropologists have pointed out, human beings have overwhelmingly preferred meat to other foods. And a number of experts attribute the general good health, increased height, and longevity of people of developed countries today to their high-protein diets.