Taurine is an amino acid, one of the building blocks of proteins. Found in the nervous system and muscles, taurine is one of the most abundant amino acids in the body. It is thought to help regulate heartbeat, maintain cell membranes, and affect the release of neurotransmitters (chemicals that carry signals between nerve cells) in the brain.

There is no dietary requirement for taurine, since the body can make it out of vitamin B6 and the amino acids methionine and cysteine. Deficiencies occasionally occur in vegetarians, whose diets may not provide the building blocks for making taurine.

People with diabetes have lower-than-average blood levels of taurine, but whether this means they should take extra taurine is unclear.

Meat, poultry, eggs, dairy products, and fish are good sources of taurine. Legumes and nuts don't contain taurine, but they do contain methionine and cysteine.