Taurine (2003 Study)
Taurine, an amino acid concentrated in the eye and found in the optic nerve, may help counter excess levels of nerve-damaging glutamate in the body. An acute dose has been clinically shown to promote blood flow during oxidative stress by restoring vessels' ability to dilate.
Fennessy FM, et al. Taurine and vitamin C modify monocyte and endothelial dysfunction in young smokers. Circulation 107:410-15, 2003.