High levels of NAC (n-acetylcysteine) supplementation have been shown to temporarily reduce homocysteine levels.[ref] Excessive supplementation with B6, methylfolate, or betaine may cause homocysteine levels to trend to the low side in some people, but this isnt well documented in research studies
Not surprising then, if too many free thiols are created you can get some more undesirable characteristics, such as vegetal, sweaty, rubbery, and over-ripe fruit in your beer
Schiess, N
1990;38(3):145-64. [PMID: 2192911]
Glutathione is a powerful antioxidant produced in your body from three amino acids: L-cysteine, glycine, and L-glutamate
It should not be treated as BPC-157