L-cysteine is a conditionally essential amino acid, one of only three sulfur-containing amino acids, the others being taurine (which can be produced from L-cysteine) and L-methionine (from which L-cysteine can be produced in the body by a multi-step process). Cysteine plays a role in the sulfation cycle, acting as a sulfur donor in phase II detoxification and as a methyl donor in the conversion of homocysteine to methionine.Cysteine also helps synthesize glutathione, the body’s most important intracellular antioxidant and a vital detoxifier.
Glutathione (gamma-L-glutamyl-L-cysteinyl-glycine) is a peptide (short-protein) molecule synthesized in the body from the three amino acids L-glutamic acid, L-cysteine and glycine. Glutathione is one of the body’s most important and powerful antioxidants, helping to detoxify xenobiotics. A major function of vitamin C is to keep glutathione in its reduced form so that it can continue to provide free radical-quenching effects.
Vitamin C, or ascorbic acid, is a white, crystalline, water-soluble substance found in citrus fruits. As an antioxidant, vitamin C scavenges free radicals in the body and protects tissues from oxidative stress. Vitamin C also promotes the absorption of iron, while preventing its oxidation. Vitamin C is a vital cofactor to the formation of collagen, the connective tissue that supports arterial walls, skin, bones, and teeth.
Because humans do not manufacture vitamin C internally, it must be obtained through dietary sources or supplements. Few people realize, however, that vitamin C is a water-soluble nutrient that is quickly oxidized and excreted by the body, which limits its efficacy. Until now, those seeking to capture vitamin C’s optimal health benefits have had no choice but to consume it several times throughout the day.