Taurine is the most abundant free amino acid in the brain, heart, and nervous system, and it plays a role in the healthy functioning of the brain, heart, gallbladder, eyes, and vascular system. It facilitates the passage of sodium, potassium, and, possibly, calcium and magnesium ions into and out of cells, and electrically stabilizes cell membranes. It maintains healthy cAMP activity, which activates important enzymes in the heart muscle, and contributes to the muscle's contractibility. Taurine is an important component of bile acids which aid in the absorption of fat-soluble vitamins. It aids the body's chemistry to support the normal detoxification process. Dietary taurine promotes the formation of taurocholate, a substance which increases cholesterol secretion in the bile and also supports fat metabolism in the liver.