N-acetylcysteine | acetylcysteine | NAC
N-acetylcysteine (NAC), a sulfur-containing amino acid, is the acetylated form of L-cysteine. The acetylation increases bioavailability compared to cysteine. NAC increases body stores of L-cysteine, which, along with glutamine and glycine, is used to make an important detoxification and antioxidant molecule called “glutathione.” This ability to support production of glutathione is NAC’s main mechanism of action. L-cysteine availability limits the rate of glutathione production (it is thought to be rate-limiting). Supplying NAC allows the body to restore intracellular glutathione levels when demand has been increased or under circumstances when it is lower (such as older age or increased toxin exposure) in tissues throughout the body (including the brain, liver, and muscles). The combination of NAC and glycine appears to be additive,[4,5] which makes sense since both are used in glutathione production. NAC promotes glutathione-related antioxidant defenses, which helps protect cells and mitochondria against free radicals, cell membrane damage, damage from metals and toxins, and other oxidative stress-related and aging issues.
NAC is used as a precursor (i.e., substrate) by the body to make glutathione. It’s this mechanism that’s our reason for including it.
In general, NAC is additive with glycine (another glutathione substrate), so it can be useful to stack the two together in formulations.
NAC sourcing is focused on identifying and purchasing from a reputable supplier and ensuring it is NON-GMO, gluten-free and vegan.
NAC is generally considered to be dose-dependent (see Neurohacker Dosing Principles) in the range it’s commonly dosed (between 400-2400 mg a day). But, side-effects of NAC also go up with higher doses. Since our use is solely to augment the supply of molecular precursors to make glutathione, and not to use NAC as part of a clinical treatment protocol, we opted to use a very low dose, primarily to gain some benefits of having a glutathione precursor (if it’s needed) while being at a dose that’s sufficiently low enough to minimize the risk of producing unwanted effects.
Immune system and cell signaling
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