Aspartic acid a non-essential amino acid that the body can make from other sources in sufficient amounts to meet its needs. It is a critical part of the enzyme in the liver that transfers nitrogen-containing amino groups, either in building new proteins and amino acids, or in breaking down proteins and amino acids for energy and detoxifying the nitrogen in the form of urea.
Recent studies have shown aspartate and arginine supplements either alone or in combination may help relieve chronic fatigue. Both amino acids are also helpful in treating decreased fertility in men caused by decreased sperm count or mobility. Aspartic acid and potassium aspartate were also helpful in treating heart attacks and preventing irregular rhythms.
Its ability to increase endurance is thought to be a result of its role in clearing ammonia from the system. In one study, 85% of 145 patients with chronic fatigue who were given the potassium and magnesium salts of aspartic acid, felt significantly more energetic. Athletes also use it to promote stamina and endurance. It helps form the ribonucleotides that assist in the production of RNA and DNA, and assists in energy production from carbohydrate metabolism.
Aspartic acid is one of two major excitatory amino acids within the brain (The other is glutamic acid). At small doses these amino acids stimulate nerve cells to higher levels of activity. At higher doses they may overexcite these nerve cells, causing cell damage or death. This is thought to happen in strokes, when large amounts of excitatory neurotransmitters are released by the damage and may contribute to further damage. Some research has shown that aspartic acid might be useful in opiate withdrawal. It was found more useful in this context than some major tranquilizing drugs.
Depleted levels of aspartic acid may occur temporarily within certain tissues under stress, but, because the body is able to make its own aspartic acid to replace any depletion, deficiency states do not occur. Aspartic acid is abundant in plants, especially in sprouting seeds. In protein, it exists mainly in the form of its amide, asparagine. The popular sweetener Aspartame is a combination of aspartic acid and phenylalanine. Aspartic acid is considered nontoxic.