Cysteine is also produced by our organism. It is formed from methionine, another amino acid, in the presence of vitamin B6 (pyridoxine). Cysteine is a high sulfur amino acid, unstable and readily converted to cystine, another amino acid, and the precursor of still another important amino acid, glutathione (see below). Cysteine is better taken together with vitamin E and selenium.


  • Antimucous agent helping to control bronchitis, emphysema and tuberculosis.
  • Antioxidant helping to reduce free radicals
  • Antitoxic agent for the control of carbon dioxide and heavy metals
  • Controls cataracts and liver disorders
  • Diminishes hangovers
  • Important agent for the formation of hair, nails and skin
  • Improves arteriosclerosis and rheumatoid arthritis
  • Promotes fat and muscle formation
  • Protects against radiation and acetylaldehyde produced from alcohol and cigarette smoke

Cysteine should be taken together with vitamin C and histidine, another amino acid.

Under no circumstances should cysteine be taken by diabetics, and especially by persons on insulin, without prior consultation with qualified and experienced health professionals.