Glutathione is a natural cellular antioxidant composed of three amino acids (a tripeptide): glycine, cysteine, and glutamine. The cell constantly synthesizes it from these amino acids. It is needed to repair cysteine residues in proteins. Proteins are abundant and contain little cysteine, but it is found in the most functional areas of proteins (it is a highly reactive amino acid). If it oxidizes, the protein loses activity and may cease functioning. It is constantly oxidized in proteins, especially in athletes, during stress, illness, toxin exposure, and so on.
So, someone, somewhere along the line, decided that since glutathione plays such an important role, it should be turned into dietary supplements/medications/cosmetics. It seemed like a good idea, but then all sorts of manipulations started:
- For example, glutathione has a very weak effect in cosmetics and will only work for a small number of people. This is due to the hydrophobic nature of the glutathione molecule. Therefore, paying extra for such cosmetics is only worthwhile for people with high transdermal permeability (for example, those with acne and allergies), or if the manufacturer uses technologies to improve permeability.
- Regarding the trendy liposomal glutathione: Yes, there are studies showing increased blood levels after taking this glutathione. BUT, unfortunately, many dietary supplement manufacturers are using improper technology. After all, the most important step in producing this type of glutathione is the creation of phospholipid nanoparticles (like nanobubbles) containing the glutathione itself. So, the manufacturer should provide this information—particle size, encapsulation efficiency, etc. Do manufacturers do this? I don't think so, or at least not all of them. This means that this type of glutathione is often simply a weak emulsion of glutathione with lecithin, and its effect is weak.
Even if we imagine a situation where we inject or administer glutathione intravenously, we must understand that it works within cells. Large amounts in the blood are excreted by the kidneys, and the "more the better" rule doesn't apply here. But in my opinion, this type of glutathione delivery is the most effective. It's especially recommended for people with polymorphisms, as there are a number of genes whose malfunctions lead to glutathione deficiency (GSS, GST, GSR genes, etc.). For example, I inject myself with insulin syringes with detachable needles into my thigh muscles about a couple of times a month (not a recommendation to repeat).
People without polymorphisms can take acetyl cysteine (NAC) and glycine. There's even a dietary supplement called GlyNAC. However, they have sufficient glutamine in their diet. This means that cells will naturally produce the required amount of glutathione from these amino acids. Moreover, studies show that the benefits of GlyNAC may be greater than those of glutathione supplementation (most likely because polymorphisms weren't taken into account). It's also important to remember that other nutrients are needed for the glutathione system to function effectively—vitamin C, vitamin B2, vitamin E, etc.
