With the popularity of “detox” diets today being what is I’m hoping some people actually want to learn how to increase their body’s natural defenses against toxins using scientifically sound dietary methods, rather than just following one of the many silly “detox juice cleanse” clogging up the internet.
With that said let me talk a little about glutathione. Glutathione is a neat little chemical made of 3 amino acids; cysteine, glutamic acid, and glycine. In addition to its role as a strong antioxidant, glutathione plays a very important role in the detoxification process by attaching to various electrophilic toxins, wherein it typically reduces their chemical reactivity and increases their polarity, causing the chemical to be excreted from the body at a greater rate.
The list of toxins to which this process occurs is massive and includes mercury, acrolein, methylglyoxal, and the toxic metabolites of benzo(a)pyrene, 7,12-benzo(a)anthracene, aflatoxin B1, acetominophen, and benzene.
The way glutathione neutralizes these chemicals involves enzymes called Glutathione S-Transferases. These enzymes transfer gluathione onto the dangerous chemicals in question. This review series will look at some dietary factors which support making and using glutathione. It will begin with coffee.
Although coffee is full of hundreds of chemicals, two in particular seem to play the biggest role in coffee’s effect of glutathione. These chemicals are cafestol and kahweol, a pair of lipid soluble diterpenes which are largely removed by paper filters but retained when coffee is made using alternative methods, such as a french press. These chemicals are one of those most heavily studied upregulators of Glutathione S-Transferase and probably explain why french press and italian style coffee increase such enzymes (as well as some other detoxifying enzymes, such as glucoronasyltransferase). In addition, coffee itself seems to increase glutathione itself in various tissues.
These facts may explain why coffee and those two diterpenes, when given to animals, seem to protect against numerous toxins known to be detoxified by glutathione. This may also explain why coffee consumption has been associated with a lower risk of certain cancers, including the liver, one of the primary sites of detoxification.
Although one should be cautious when extrapolating to real life situations, I think their is decent evidence to suggest that coffee, particularly coffee made using a french press or similar devices, has a place in a “detox” diet, should such a thing even be needed in first place (I’ll hold onto my opinions here).
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