Antioxidants prevent chronic diseases like heart disease?

We thought so..: So we knew that oxidative stress is a key factor in cancers and other disease processes. So naturally we thought, lets load patients with antioxidants to prevent that. We did studies and it showed antioxidants have no effect. Which means there's a lot more to it than the oxidation issue. So although logic says antioxidants are good, we just don't have definitive proof of it.