Amino acids are the building blocks of proteins in the body and are singly responsible for 75% of the dry body weight (i.e. sans water). They are needed for the production of proteins, hormones, neurotransmitters, neuclei acids and peptides. These are the structural components of the every tissue, organ and cell in the body. Amino acids are likewise needed for normal biochemical processes and overall functioning, differentiation and organization of cells, tissues and organ-systems.
There are 22 amino acids, eight of which are classified as essential. These are leucine, isoleucine, lysine, methionine, phenylalanine, threonine, valine and tryptophan.
Essential amino acids are so classified because they are not produced in the body at levels high enough for normal bodily functioning. The other amino acids are adequately produced in the body and are so classified as non-essential amino acids. However, five of these can be called semi-essential amino acids because while they are produced in adults, their means of production in children are not fully developed. These amino acids are histidine, cysteine, taurine, arginine and tyrosine.
Amino acids can exist in either the D or L forms. These forms are purely the same molecules but in opposite optical orientations. The L form is the form in which the human body utilizes amino acids except for phenyalanine which can be used in both forms. This is important since the inclusion of D forms amino acids in supplement formations is mostly perfunctory and not important.
Only three amino acids are classified as branched chain amino acids (BCAA). These are leucine, isoleucine and valine. The importance of branched chain amino acids stems from their usefulness in enhancing the immune system and improving stamina and endurance. These make them right for bodybuilders and athletes as well as in the treatment of certain diseases.
The primary function of most of the amino acids is the production of proteins. Each amino acid is linked to two others in short linear chains of peptides. Longer peptides are called polypeptides or proteins when fully folded. The entire process is mediated by mRNA (messenger ribonucleic acid) which itself is built of amino acids. Apart from protein production, amino acids can also precursors of other molecules such as neurotransmitters, heme in the hemoglobin of the red blood cell, polyamines, nucleotides and nitric oxide.
Therefore, the benefits of amino acids supplments extend beyond their importance as protein building blocks but also include their importance to metabolism, growth, reproduction and immunity. All amino acids both essential and non-essential are essential for optimal body functioning. Deficiency in one amino acid can result in hormonal and growth imbalance and can have far-reaching consequences. This is because amino acids mediate essential biochemical reactions as well as serve as building blocks for important molecules needed in these same reactions. Therefore, deficiency can quickly result in general body malfunction, the source of which can be difficult to prove. This is why amino acids supplementation is important.
The food sources of amino acids include fruits and vegetables, grain, meat and dairy products. However, supplements may be required to augment uptake of amino acids from restricted diets or in those with digestive problems. Those for which amino acids supplementation is an absolute necessity include vegetarians, people with chronic diseases, those with allergies, people on poor diets and everyone undergoing stress. The need for amino acids supplementation can range from clear signs such as wasting and specific metabolic dysfunctions to vague indicators such as malaise, weakness and exacerbation of stress.
Certain amino acids can offer specific benefits. For example:
- Arginine is used for male infertility,
- Taurine recommended for epileptics and diabetics,
- lysine given to combat Herpes simplex,
- cysteine and glutamine used in HIV support therapies
- glutamine given to ulcer patients,
- L-phenylalanine used for people suffering from Parkinson’s disease and Vitiligo;
- and histidine to treat rheumatoid arthritis.
Some amino acids are also useful for athletes to gain lean muscles, promote endurance and hasten healing (glutamine and BCAAs); they can also help with weight loss and are used in children to treat ADHD. However, generally, amino acids help develop and maintain the muscular, digestive, cardiovascular, neurological and immune systems.
Amino acids supplements usually are formulated in combinations of different amino acids. The presentation can be as powder, capsules, tablets and in liquid forms. Some amino acids are perfectly safe while some may present with side-effects (tyrosine at high doses can cause anxiety, rapid heartbeats, palpitation and restlessness). A fine balance of amino acids is needed in supplementation so as not to overlabor the liver. Vitamins B6 and C are especially useful for the absorption of amino acids and are usually recommended along their supplementations.