Taurine is found in high concentrations in the retina, especially in the photo-receptor cells.
Taurine stabilizes cell membranes and regulates the movement of ions across the membrane. It seems to protect cells against UV damage, changes in ion concentrations and even toxins.
Taurine thus plays an important role in rejuvenation and regeneration of retinal cells. Dietary taurine deficiency causes degeneration of photo-receptor cells in cats. In monkeys, deficiency of taurine causes morphological change to the photo-receptor cells as well as decreased visual acuity
Rats given a drug that blocks taurine uptake showed changes in RPE and photo-receptor cells as well as electroretinographic (ERG) findings similar to damage from excess UV exposure.
Taurine is considered a non-essential amino acid because it can be made from cysteine, but the amounts humans are capable of manufacturing is very small. For example, children fed a diet without taurine show low plasma taurine and abnormal ERG’s, with restoration of normal blood levels and retinal function in most cases upon taurine supplementation.
Animal studies also show that retinal degeneration caused by its removal from the diet are reversed with taurine supplementation. A study in adults also showed low levels of taurine produced in the urine when the diet was low in this ‘non-essential’ amino acid.
Animal studies also show a decline in taurine with age. Bacterial dysbiosis (imbalance) in the intestinal tract may result in deficiency of this important amino acid.
A supplemental dose of 100 mg/day of taurine has been recommended.
