What is Protein?
Protein is made up of numerous chemical combinations. The basic structure of protein is amino acid chains, which can
form many different configurations and can combine with other substances. Proteins are constantly broken down in the
body. Proteins are described as essential and nonessential proteins or amino acids. The human body requires
approximately 22 amino acids for the synthesis of its proteins.
The body can make only 13 of the amino acids; these are known as the non-essential amino acids. They are called
non-essential because the body can make them and does not need to get them from the diet. However, some need to
be replaced. There are nine that are considered to be essential. These cannot be manufactured by the body and must
be supplied by the diet. (Or if the protein in a food supplies enough of the essential amino acids, it is called a complete
protein. If the protein of a food does not supply all the essential amino acids, it is called an incomplete protein.)
The average protein requirement for women is 50 grams per day and 60 grams per day for men. Meat and other animal
products are the most readily available sources of complete protein. The protein content of cooked meat and dairy
products is between 15% and 40%. In contrast, cooked cereals, beans, lentils, and peas range from 3% to 10%.
Vegetarians can get enough protein if they eat a well-balanced diet of grains and vegetables, like brown rice, whole
wheat pasta, soy products, and beans. (Or all meat and other animal products are sources of complete proteins.
These include beef, lamb, pork, poultry, fish, shell fish, eggs, milk, and milk products. Protein in foods (such as grains,
fruits, and vegetables) are either low, incomplete protein or lack one of the essential amino acids. These food sources
are considered incomplete proteins.)
Plant proteins can be combined to include all of the essential amino acids and form a complete protein. Examples of
combined, complete plant proteins are rice and beans, milk and wheat cereal, and corn and beans.
You need adequate protein to build muscle, but if 10-15% of your diet is protein, you are getting enough to maintain
and add new muscle and tissue. It is a myth that super-high protein diets assist in increasing lean muscle mass or give
athletes a competitive edge. Any excess protein will be stored as fat, not muscle. Plus, the conversion of large amounts
of protein to fat puts stress on both the kidneys and the liver.
Protein constitutes three-fourths of our body tissue (excluding the water). Muscles, organs, antibodies, enzymes, and
some hormones are largely composed of proteins. Other key body functions include tissue repair, fluid balance, blood
clotting, and vision.
Eggs, milk, fish, beef, peanuts, oats, rice, whole wheat products, corn products, soybean products, sesame seeds,
peas, and beans are all good sources of protein.