I'm quite unique in that I have abnormally high levels of Cystathionine & Cysteine, with concurrent high levels of Formiminoglutamic acid. This was kinda confirmed after taking NAC made me feel 10x worse.
However, for people with high Cystathionine-Beta Synthase, although there are a few supplements to reduce Ammonia (Arginine/Ornithine, Carnitine) there appears to be little information on how to fix the high cysteine levels, which can actually contribute to cancer and neurological abnormalities.
However, I found 1 study that says that a special form of B12, Hydroxocobalamin, reduces Cysteine:
http://cancerres.aac...0/4727.full.pdf
Having low Tetrahydrofolate as well as high Cysteine can be a bitch, because supplementing with methyl-donors is just going to go down the drain. So, taking Hydroxocobalamin along with 5-MTHF may be a good way to go.
Edited by agwoodliffe, 23 March 2014 - 07:14 PM.