|While your body needs all of the amino acids in varying forms and amounts, there are benefits to taking specific individual free form amino acid supplements. For example, the richest dietary sources of amino acids are animal foods, but they contain unwanted levels of fat. Some of the individual amino acids;|
Arginine is considered semi-essential, since adults make adequate amounts of arginine; however during periods of growth, arginine is required. Therefore, arginine is necessary for growth, but not for maintenance, of the body.
Arginine also helps remove ammonium from the body, supports immune function,' and promotes the secretion of several hormones, including glucagon, insulin and growth hormone. Arginine is also a precursor to nitric oxide, which aids blood vessel dilation.
The body makes carnitine from lysine and methionine, so carnitine is considered non-essential. Carnitine helps release energy from fat and helps support a healthy cardiovascular system.
The body makes glutamine from glutamate and glutamic acid and therefore is non-essential. Glutamine serves as a source of fuel for cells lining the intestines. Glutamine is the dominant amino acid in blood and cerebrospinal fluid. It is also necessary for the synthesis of other non-essential amino acids.
As an essential amino acid, Lysine plays several roles in the body, including the regulation of nitrogen balance and the absorption of calcium. Lysine is also important in the formation of collagen. Research suggests that lysine may play a role in blood pressure maintenance, cholesterol levels, and the body's susceptibility to certain viruses.
Cystaine and N-acetyl Cysteine (NAC)
Cysteine, another non-essential amino acid, is one of the
few amino acids that contains sulfur. The functions of cys- teine and NAC include being a component of the important antioxidant glutathione and helping to produce the amino acid taurine. In addition, cysteine strengthens the protective lining of the stomach and intestines and has a role in the proper function of the immune system.
Histidine is another semi-essential amino acid since adults generally produce adequate amounts, while production may not be adequate during periods of growth. Histidine is also a precursor of histamine, a compound released by immune sys- tem cells during an allergic reaction, auto-immune response or trauma. Research reports that adequate histidine levels may be necessary to maintain healthy joint function.
Methionine, an essential amino acid, supplies sulfur and other compounds required by the body for normal metabolism and growth. Methionine also belongs to a group of compounds called lipotropics (the others in this group include choline, inositol, and betaine). As a lipotropic, methionine helps the liver to metabolize fats.
Methionine, along with lysine, is also used by the body to produce camitine. Excessive methionine intake, particularly if B-vitamin intake is inadequate, can increase the conversion of methionine to homocysteine-which in turn may cause high homocysteine levels, adversely affecting the heart.
Non-essential ornithine is manufactured by the body when another amino acid (arginine) is metabolized during the production of urea. Although some research suggests that omithine promotes muscle building activity in the body, other studies do not support this claim.
This essential amino acid can be converted to tyrosine, which in turn, is used to manufacture L-dopa, epinephrine and norepinephrine. Phenytalanine can also be converted (through a separate pathway) to phenylethylamine, a naturally-occurring substance in the brain that may play a role in mood. DL-phenylaianine is a mixture of the natural L-phenylaianine form of the amino acid and its mirror image D-phenylaianine.
Non-essential tyrosine can be made from phenylalanine. Tyrosine is the precursor of several neurotransmitters, including L-dopa, dopamine, norepinephrine, and epinephrine. Tyrosine is formed by skin cells into melanin (natural skin pigment. Thyroid hormones also contain tyrosine as part of their structure.
Non-essential taurine is made from methionine (except by infnts). Taurine serves as a constituent of bile acid, which in turn are needed in the absorption of fats and fat-soluble vitamines. Other important functions of taurine may include the regulation of calcium and potassium levels in the heart. Diabetics have been found to have lower blood levels of taurine since it has an influence upon blood sugar levels