Read All About Amino Acids

Amino acids are the foundation upon which life is built. Proteins are formed from these compounds and cannot exist nor carry out their work without the proper combination of amino acids. After water, protein is the second most plentiful substance in the human body.

There are approximately twenty-nine commonly known amino acids that account for the hundreds of different types of proteins present in all living things. The liver produces about 80 percent of the needed amino acids; the remaining 20 percent must be obtained from outside sources. Essential amino acids are those which cannot be synthesized within the body and must be obtained through dietary sources.

The essential amino acids are: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Those amino acids which can be synthesized internally by the body are considered nonessential.

The nonessential amino acids are: aspartic acid, asparagine, glutamic acid, glutamine, glycine, proline, serine and tyrosine.

Arginine and histidine are labeled semi-essential because they do not fall perfectly into either of these categories. They become essential during times of growth, when the body cannot produce them in adequate amounts.

Amino acids are referred to by their prefixes L- (for levorotatory, or "left-handed"), or D- (for dextrorotatory, or "right-handed"), indicating slight differences in molecular structure. L-series amino acids are in the same form as amino acids in plant and animal tissue, and are much more common than either the D- form or the mixed DL- form.