Amino acids combine in different ways to make many different kinds of proteins.
Protein from the diet is broken down into its individual amino acids; they are then used to create the proteins needed by the body.
Muscle, skin, hair, fingernails, antibodies, many hormones, and enzymes are made from proteins.
What are the essential amino acids?
All of the different proteins in the body are built from 20 amino acids.
The body can make some amino acids. These are called non-essential amino acids since they do not necessarily need to be in the diet.
There are eight essential amino acids that the body cannot make: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
The essential amino acids must be provided in the diet for continued good health.
Histidine is semi-essential since the body does not always require a dietary source for this amino acid.
Balancing intake of amino acids
Muscle tissue is broken down if the diet does not provide enough protein.
The average diet provides more protein than is needed by the body.
Too much protein can be a burden on the kidneys.
Foods of animal origin, such as meat, fish, poultry, eggs, and dairy products, contain all of the essential amino acids.
Plant sources of protein include beans, peas, and grains.
The need to combine plant-based proteins (such as beans and rice) is an outdated belief; in an average diet protein deficiencies rarely occur. Those following a strict vegetarian or vegan diet may need to be more vigilant in their protein intake.