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Amino Acids


Amino Acids

Amino Acids are the building blocks of protein. Amino Acids are linked in various sequences and chains (polypeptides), thus accounting for the vast variety of different proteins manufactured by the body. Likewise, our dietary protein differs, and its subsequent utilization by the body.

Scientists have attempted to measure utilization rates of different sources of dietary protein, creating various forms of measure, such as Protein Efficiency Ratio (PER) and Biological Value (BV), which you may've come across on the back of your protein supplements tub.

Other tags, relating to Amino Acids, which you may be familiar with (from reading the back of protein supplements), are the prefix "L" and the noting "BCAA".

An "L" prefix denotes a naturally occurring amino acid. The opposite "D" (which you're probably not so familiar with) is synthetic, and is not normally useful to the body.

"BCAA" is short for Branch Chain Amino Acids. Bonded in a chain configuartion, the BCAA's - Leucine, Isoleucine, Valine - collectively form the largest Amino section of human protein (about 33% of MUSCLE protein!).

Naturally occurring Amino Acids are further categorized as "essential", which means that they cannot be made by the body (&, subsequently, have to be included in the diet), and "non-essential", which can be made by the body (NB: Although, still beneficial within diet).

A list has been made below, click on each link to find out more info. on each individual Amino Acid. However, it must be remembered that many work hand-in-hand, and adequate amounts of protein, and good sources of protein (remember, this is what Amino Acids collectively form), are of greater importance and benefit than simply supplementing high dosages of certain Amino's.

Essential Amino Acids:


L-Isoleucine (BCAA)
L-Leucine (BCAA)
L-Lysine

L-Methionine
L-Phenylalanine
L-Threonine
L-Tryptophan
L-Valine
(BCAA)

Non-Essential Amino Acids:

L-Alanine
L-Arginine*
L-Asparagine

L-Aspartic Acid
L-Cysteine
L-Glutamine
L-Glutamic Acid
L-Glycine

L-Histidine*
L-Ornithine
L-Proline
L-Serine

Taurine**
L-Tyrosine

*These are regarded as "semi-essential". The reason, they can be made by the adult body, but babies and young children may not be able to manufacture enough for their needs.

**Taurine does not have an "L" prefix as it only exists in one form. Furthermore, Taurine's unusual as it's not incorporated into proteins in the body (likewise, L-Ornithine).

Tell me more about:

Amino Acids
Dietary Protein
Nitrogen Balance
Protein Requirements

Protein Source Comparisons
Protein Efficiency Ratio (PER)
Biological Value (BV)
Net Protein Utilisation (NPU)

Protein Fractions
Protein Supplementation