interestingly... it may be the grapefruit which led to synergy of "the same stuff everyone else is taking" which is responsible for his insane conditioning. It sounds like Kai found a nice synergistic stack the rest of the world has now.
Grapefruit can have a number of interactions with drugs, often increasing the effective potency of compounds. Grapefruit contains naringin, bergamottin and dihydroxybergamottin, which inhibit the protein isoform CYP3A4 predominately in the liver. It is via inhibition of this enzyme that grapefruit increases the effects of a variety of drugs.[11][12][13][14][15] The effect of grapefruit juice with regard to drug absorption was originally discovered in 1989. However, the effect became well-publicized after being responsible for a number of deaths due to overdosing on medication.[16]
Grapefruit juice may be the first documented, but apple and orange juices have been also implicated in interfering with etoposide, a chemotherapy drug, some beta blocker drugs used to treat high blood pressure, and cyclosporine, taken by transplant patients to prevent rejection of their new organs.[17]
