Taurine is one of the sulphur amino acids. Unlike the others it is not incorporated into muscle proteins but it is the second most abundant free amino acid in the brain. Within the brain taurine is concentrated in the taste and smell centre, the memory centre and the pineal gland, and it has neurotransmitter functions. It is present in cell membranes, helping to stabilize them electrically and facilitating the passage of sodium, potassium and calcium ions in and out of cells. This role may account for taurine’s usefulness in the treatment of epilepsy, seizures and convulsions. Taurine is also an inhibitory neurotransmitter.
Taurine is the most abundant amino acid in the heart, and has been successfully used in supplement form to combat congestive heart failure, by regulating calcium and potassium in heart muscle cells, (and therefore in nerve impulses in the heart), by acting as a heart stimulant and by encouraging the excretion of sodium and water. Taurine is needed for the formation of taurocholic acid, which helps to break down fats in the small intestine. It is also needed in large amounts by the eyes.
One of taurine’s most important roles is in detoxification. It is needed for conjugating toxic substances, and as an antioxidant, especially for the hypochlorite ion, formed by the oxidation of chloride ions, and itself a powerful oxidizing agent. Because the hypochlorite ion requires adequate amounts of the amino acid taurine to control and scavenge it, taurine-deficient individuals may become very sensitive to aldehydes, chlorine, bleach and other similar chemicals, and free amino acids in their body may become toxic aldehydes. For this reason infant formula feeds should always be enriched with taurine at least to the levels found in human breast milk.
Except for young babies, the human body is able to make taurine from the amino acid cysteine although it is not known whether this is always enough for our requirements. Taurine is found in breast milk, meat, fish and organ meats. The food additive monosodium glutamate can reduce taurine levels. Adequate zinc, vitamin A and vitamin B6, and adequate methionine intake and metabolism are required to maintain normal taurine levels in the body. Poor kidney function may result in taurine depletion. High levels of the amino acid beta-alanine, which may occur if vitamin B6 is deficient, can result in excess losses of taurine through the urine.
In one research study, taurine supplementation was found to reduce dementia in elderly people.