Taurine is a non-proteinogenic (i.e., it is not incorporated into proteins during translation) sulfur-containing beta-amino acid that is omnipresent in the body and is particularly abundant in electrically excitable tissues such as the heart, retina, brain, and skeletal muscle.[1]
A small amount of taurine is produced in the liver from the metabolism of cysteine (which is itself derived from the essential amino acid methionine). Taurine can also be obtained directly from certain foods like beef, dark-meat poultry, and, most abundantly, shellfish such as scallops and mussels.[2][3]
Taurine is considered a conditionally essential nutrient, meaning that we can produce it in our bodies, but under certain conditions may not produce enough to meet all of our functional needs. Because taurine can be produced in the body, the average adult probably doesn’t need to be concerned about overt symptoms of taurine deficiency.[4] (In this, humans are unlike cats and monkeys, who develop retinopathy and cardiomyopathy with inadequate taurine intake.[5][6][7][8][9][10]) However, low plasma taurine levels are associated with various conditions, such as cardiovascular disease and type 2 diabetes.[11][12][13]
In accordance with its ubiquitous presence in the body, taurine has diverse physiological functions. It is known as a cell-protecting agent and is involved in osmoregulation, modulation of mitochondrial function and endoplasmic reticulum stress, cell membrane stabilization, conjugation of bile acids, calcium homeostasis, energy metabolism, neuromodulation, and anti-inflammatory and antioxidant actions.[14][15][1]
