The 20 or so amino acids are the molecular building blocks of proteins. According to one accepted classification, 9 are termed indispensable amino acids (IAA, sometimes called essential), meaning that they must be supplied from some food or supplement source; the others, which used to be classified simply as nonessential, are now more correctly termed dispensable amino acids (DAA) or conditionally indispensable, based on the body's ability to synthesize them from other amino acids.

You may not give it much thought when you sink your teeth into a chicken breast (or lentil stew), but the content and balance of amino acids, particularly the ratio of IAA to DAA, is what determines the body and health building value of a protein food or supplement. But that isn't all that matters.

In addition to being influenced by the carbohydrates, fats and total calories associated with it, protein quality is related to the amount of the specific aminos within both the IAA and DAA categories (for example, the amount of glutamine and branched chain amino acids, or BCAAs - leucine, isoleucine and valine). While the amount of IAAs are generally of greater importance, the DAAs are also significant because they're synthesized too slowly to support maximum growth. Even if a source has a perfect amino acid profile for a given individual and lifestyle, another important factor - to what extent these acids are actually delivered to the tissues when needed - must be considered. That, in turn, raises the issues of digestion, absorption, actual bioavailability and the potential value of supplementation

* THIS ARTICLE IS A CORRECTION OF PREVIOUS ARTICLE ON 'AMINO ACIDS'.Amino acids is one of the 20 buiding blocks of protien and not 23.

Sorry for the error.

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