Resveratrol and medications.

Resveratrol is a polyphenol found in grape skin and red wine, sold mostly as the trans isomer, which is the only form with activity. In mice it extended lifespan by mimicking calorie restriction through the sirtuin pathway, and that animal data is genuinely compelling. Human trials have been disappointing in most outcomes. The likely reason is very rapid first-pass metabolism, so most of a supplemental dose may never reach tissue at meaningful levels, and sirtuin activation at these doses stays unproven in people. This is a Grade C compound, reserved for longevity goals in someone over 45 who already has the better-evidenced options in place. The interaction angle matters more than the benefit. Resveratrol inhibits CYP3A4, so it can raise the blood levels of medicines cleared by that enzyme: statins, calcium channel blockers, and transplant immunosuppressants such as tacrolimus and ciclosporin. It can also change the levels of some HIV antiretrovirals. For these narrow-window medicines (transplant immunosuppressants and several antiretrovirals) it is best avoided without your transplant or HIV specialist's oversight, because even a small shift in drug level can cause harm. It also has a mild blood-thinning effect worth flagging on warfarin, aspirin or newer blood thinners (DOACs). It also shows oestrogenic activity at high doses, so it is excluded in hormone-sensitive cancers.