If you’ve been knocking yourself out at the gym lately, you may not want to read this.

What gives red wine it’s healthy kick is resveratrol, a natural phenol found in the alcoholic beverage.

There is a caveat, however. Most studies on resveratrol have been performed on rodents, and scientists aren’t sure if resveratrol is quite as beneficial to humans. In fact, one theory suggests humans would have to consume a lot more that one glass of wine to reap resveratrol rewards.