Not all resveratrol supplements are created equal. Understanding purity and potency is essential for getting real results from your supplementation.
Purity refers to the percentage of trans-resveratrol in the total resveratrol content. A supplement claiming 500mg of resveratrol might only contain 50mg of active trans-resveratrol if it's only 10% pure. Always look for the trans-resveratrol percentage on the label.
High-quality supplements typically contain 95-99% trans-resveratrol. Anything below 90% should be viewed with skepticism. Some products deliberately obfuscate this information by only listing total resveratrol content.
Resveratrol is typically extracted from Japanese knotweed (Polygonum cuspidatum) or grape skins. Japanese knotweed provides higher concentrations and is more cost-effective, which is why it's the preferred source for quality supplements. Grape-derived resveratrol isn't inherently better despite marketing claims.
Look for these key pieces of information on supplement labels:
A 500mg supplement with poor bioavailability may be less effective than a 300mg supplement with absorption enhancers. This is why formulations including BioPerine or micronized resveratrol often outperform higher-dose competitors.
Be wary of supplements that:
For verified, high-purity options, see our top-rated supplements. Learn more about resveratrol on our information page.