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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, one of the body’s most important natural detoxifiers.

N-acetyl-cysteine (NAC) is the acetylated form of L-cysteine, which is more efficiently absorbed and used because it may protect the cells directly.57-69

NAC is an antioxidant and a free radical-scavenging agent that increases intracellular GSH, at the cellular level. NAC can act as a precursor for glutathione synthesis as well as a stimulator of the cytosolic enzymes involved in glutathione regeneration.  NAC has been shown to protect against oxidative stress-induced neuronal death in cultured granule neurons.70

The liver is a large glandular organ, whose functions include storage and filtration of blood, secretion of bile, detoxification of various substances, and conversion of sugars into glycogen, which it stores. The liver is also responsible for processing many vitamins and nutrients into a form that can be utilized by the body, and processing many toxic chemicals for elimination.

Modern living involves daily exposure to substances that are toxic to our bodies, which imposes a heavy load on the liver. Therefore, a healthy liver is critical to well-being. Certain lifestyle risks and medical conditions make it all the more important to ensure that the liver is being maintained at its functional best.

N-acetyl cysteine is the more efficiently absorbed and used form of the amino acid, L-cysteine. L-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. N-acetyl cysteine has antioxidant properties and is a glutathione precursor. In addition, N-acetyl cysteine is used to support bronchial health.35-45*

Those who supplement with NAC should drink 6 to 8 glasses of water daily in order to prevent cysteine renal stones. Cysteine renal stones are rare but do occur.