N-acetyl cysteine (NAC) is an altered form of the non-essential amino acid cysteine, which is commonly found in food and synthesized by the body. The oral cysteine that is best tolerated is called N-Acetyl Cysteine.
Indications are that N-acetyl
cysteine is anti-aging; anti-oxidant; a powerful aid in protecting the body from radiation; it deactivates
free radicals; is vital for the formation of skin and cell recovery particularly after surgery or cellular damage from burns. Hair and skin contain cysteine.
Source
Cysteine, the
amino acid from which NAC is derived, is found in most high-protein foods. The food that contains most cysteine is egg yolk. NAC is not found in the diet.
L-Cysteine is found either by itself or with other
amino acids for general amino acid supplementation. It is also found in formulas designed for detoxification, as it has been in veterinary science for some time.
Function; Why it is Recommended
Cysteine (L- Cysteine) is one of 20
amino acids used by our bodies to make protein molecules. Cysteine, also known as beta-mercaptoalanine, and the
amino acid methionine are the two sulfur-containing amino acids. Cysteine is a vital component of many proteins in the body, including all of those whose structure is dependent on a disulfide bond (for example,
antibodies).
Cysteine has been used for many years in the veterinary sciences as a detoxifying agent. It has the ability to bind metals such as cadmium and mercury, able to prevent acetaldehyde poisoning (from chronic alcohol or cigarette smoking), and has the ability to increase the activities of both
Vitamin B6 and
glutathione.
NAC helps the body synthesize glutathione, an important
antioxidant. Cysteine is the rate-limiting
amino acid in the production of glutathione. In other words, if one is low in cysteine, the production of glutathione can not move forward. Many studies have shown that supplementation of cysteine has led to increased intercellular levels of glutathione.
Deficiencies of NAC have not been defined and may not even exist. Healthy people do not need to supplement NAC.
The use of N-Acetyl L-Cysteine in medicine is well researched and documented for a variety of conditions. NAC is a precursor to one of the body's most potent anti-oxidants,
glutathione. It is through this action, that NAC is used for help in
liver support, and has even been used to prevent acetaminophen (Tylenol) poisonings.
Probably its best-known use is as a
mucolytic. By breaking the disulphide bonds in the mucus of the intestines and especially the
lungs, NAC is able to break down the mucus and make it less viscous. This is especially important during
asthma,
bronchitis, and bouts of hayfever.
As an
antioxidant, NAC has a number of scavanging activities that benefit many organ systems and is often used in antioxidant supplements.
Instructions
Optimal levels of supplementation remain unknown, though much of the research uses 250-1,500mg per day.