Taurine is a sulfur-containing amino acid that naturally occurs in animal products such as meat, fish, and dairy. Unlike many other amino acids, taurine is not used for building proteins.

Taurine is a so-called conditionally non-essential amino acid. This means that animal organisms can produce taurine themselves under normal circumstances, but supplementation through diet or supplements may sometimes be desirable.

Although taurine naturally occurs in animal products, industrial taurine is synthetically made. As a result, it does not come from animal sources and is suitable for vegetarians and vegans. The synthetic form has the same chemical structure as the natural variant.

Essential amino acids must be obtained through the diet because animal organisms cannot produce them themselves. Non-essential amino acids can often be produced internally. Conditional amino acids, such as taurine, are in between.