Glutathione is a tri-peptide made from three amino acids: cysteine, glycine, and glutamate. Cysteine seems to be the rate limiting amino acid; hence it’s use in replacement by those attempting to increase glutathione levels.
Glutathione is perhaps the most important molecule in our bodies in the areas of antioxidant protection and detoxification (getting toxins out of the body). Glutathione is involved in the binding of toxic metals to prepare them for excretion in the urine. Mitochondria are not only the power houses for energy in the cells but also the location where most reactive oxygen species (ROS) from oxygen consumption and the death of cells occurs. It is these redox reactions that are involved in most inflammatory disorders, oxidative stress, and diseases. Glutathione is perhaps the most important anti-oxidant and it is vulnerable when the methylation cycle is compromised, or cell membrane mitochondrial carriers are compromised (the mitochondria do not make their own glutathione).
Glutathione spares the other key antioxidants (vitamin C, vitamin E, Carotenoids, and selenium) by reducing oxidized forms and by eliminating hydrogen peroxide by reacting with glutathione peroxidase. Glutathione is involved in the formation of certain prostaglandins, important in inflammation and to decrease oxidized LDL that is implicated in atherosclerosis.
SYMPTOMS OF DEFICIENCY
Most diseases of civilization; aging, atherosclerosis and heart disease, arthritis and auto-immune disorders, neurodegenerative diseases, autism, and infections and pulmonary diseases are made worse by oxidative stress and free radicals. In AIDS, T-lymphocytes become glutathione depleted and function better when it is supplemented.
It may be safe to say that glutathione depletion or inadequate glutathione function could be one of the most significant issues in the development of many chronic diseases, but you won’t be aware of this until decades later in most cases.
Meats, yogurt, wheat germ, and eggs are highest in cysteine, the key amino acid needed for the production of glutathione.
SAFETY AND TOXICITY
By itself, glutathione is not stable and thus generally not advisable to be taken as a supplement. There may be some liposomal preparations of glutathione that may be safe and prevent the oxidation (spoiling) of the glutathione, but this is questionable, and oxidized glutathione would do more harm that good. There is no specific toxicity reported for glutathione.
Oral glutathione is only 10% absorbed. There are transdermal preparations that also get absorbed at about 10% and often smell bad, however they have the advantage of not causing GI upset that is common with oral preparations. Oral doses have been used at 10-15 mg / Kg / day, and should not to exceed 300 mg daily.
Supplementation of NAC (N-Acetyl-Cysteine) has been shown to be safe up to doses of 2000 mg daily. Many do not recommend its use as it can promote yeast overgrowth in the intestines if you have a yeast issue. Antifungal treatments may be needed before or after use of glutathione or cysteine and a diet low in sugars may be helpful in minimizing the yeast overgrowth issue.
There is no RDA listed for glutathione. This is one supplement you would be wise to undertake under the care of a knowledgeable physician.
Vitamin C at 500 mg daily has been shown to increase glutathione levels. Support of the methylation cycle with, methyl-B12, methyl-folate, and TMG (trimethylglycine) has been shown to increase glutathione levels.
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