Taurine is an amino acid that is produced via L-cysteine metabolism and is the primary intracellular amino acid found in humans and other species of animals. Especially high concentrations of taurine are found in the brain, retine, myocardium, muscle, platelets, and neutrophils. It is considered a conditionally essential amino acid because it is required in the diet of infants for normal retinal and brain development. Taurine is used to help absorb fats and fat-soluble vitamins as well as to regulate the heart beat, maintain cell membrane stability, and prevent brain cell over-activity. It is also believed to be useful in protecting against congestive heart failure. Taurine possesses antioxidant activity and offers putative hypocholesterolemic, hypotensive, antiatherogenic, and detoxifying activities. Some researchers report that taurine may offer assistance to those with cystic fibrosis as it exhibits steatorrhea-reducing activity and has putative antidiabetic, inotropic, and antiseizure activities. In fact, some clinical trials have shown that cystic fibrosis patients receiving taurine supplements experience a decrease in steatorrhea. It is believed that taurine stimulates the production of bile acid resulting in increased fat absorption which leads to decreased steatorrhea.