Glutathione is the most powerful antioxidant and immune booster for your body. It also helps maintain and recycle other antioxidants, such as vitamins C and E, to maintain their antioxidant abilities. A mixture of three amino acids, glutathione improves your health, helps detoxify your body, and regenerates your immune cells to boost your efficiency for fighting off diseases. Glutathione is also vitally important in the synthesis and the maintenance of your DNA, which is necessary for the synthesis of proteins and amino acids.
If your body doesn’t have adequate glutathione present, one of the most common complaints is fatigue or a feeling of exhaustion. In addition, without adequate glutathione you cannot detoxify your body adequately, which can also contribute to fatigue. Glutathione is very important in many metabolic pathways.
As an antioxidant, glutathione plays an important role in the removal of synthetic chemical toxins, carcinogens, and free radicals that can potentially destroy your cell’s DNA. It is essential in protecting your cells from the aging effect of oxidation. It also activates enzymes vital for the removal of toxic byproducts and factors that build up at the cellular level during normal metabolism.
Glutathione has exceptionally strong antiviral effects. High levels of glutathione in the body’s tissues and blood serum have been shown to inhibit and prevent the replication of virtually all pathogens. Conversely, if the levels of glutathione are too low in the body, the body is far more susceptible to virus and pathogen invasion.
Low levels of glutathione is commonly seen in patients undergoing “wasting” or negative nitrogen balance such as is seen in patients with cancer, HIV/AIDs, sepsis, trauma, burns and athletic overtraining. It is thought to help protect against cancer and other diseases caused by oxidative damage.
Glutathione also plays an important role in the regulation of immune cells,
Glutathione is synthesized in your body from three amino acids, L-cysteine, L-glutamic acid and glycine. Of the three, cysteine levels seems to be the most difficult to elevate since this amino acid is relatively rare in foodstuffs. Thus, it may be important to take extra cysteine to help manufacture more glutathione. The rate limiting step in production of glutathione is combining of cysteine to glutamic acid.
There is controversy whether taking glutathione supplementation increases your glutathione levels. One study in 1992 stated that “it is not possible to increase circulating glutathione to a clinically beneficial extent by the oral administration of a single dose of 3 g of glutathione.”  However, a recent study in 2014 refuted this statement and demonstrated that daily consumption of glutathione is effective at increasing glutathione blood levels.
Foods rich in glutathione include fruits and vegetables, especially asparagus, avocado, walnuts, eggs, dairy products, beans, fish, poultry and red meats. Supplements can be used to boost glutathione levels, including N-acetylcysteine, SAMe, and whey protein.
It is possible to increase and maintain good glutathione levels by ingesting adequate amounts of foods rich in glutathione and/or supplements. In addition, adequate vitamin D is necessary since a metabolite of Vitamin D, calcitriol, increases glutathione levels in the brain and appears to be a catalyst for glutathione production.
Supplements that can increase the production of glutathione in the body include n-acetylcysteine, S-adenosylmethionine (SAMe),,,  and whey protein., ,  All have been shown to increase cellular glutathione content. Zinc is also an important mineral for the production of glutathione.,, 
If you want to boost your glutathione levels with supplementation, consider taking the following:
- S-Acetylglutathione (a well absorbed oral glutathione product; 200 mg capsule taken twice a day)
- N-acetylcysteine (NAC available in 600 mg capsules; take once a day)
- SAMe (also boosts mood; available in tablets of 400 mg; take twice daily)
- Whey Protein (great for making protein shakes; do twice a day)
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