'Alcohol damages cells and resveratrol kills damaged cells,' says a scientist who studied red wine and its relationship to preventing cancer. "Alcohol bombards your genes. Your body has ways to repair this damage, but with enough alcohol eventually some damage isn't fixed. That's why excessive alcohol use is a factor in head and neck cancer. Now, resveratrol challenges these cells -- the ones with unrepaired DNA damage are killed, so they can't go on to cause cancer. Alcohol damages cells and resveratrol kills damaged cells," he says.