Vitamin E And C Don't Change Cancer Risk, Long Term Study 17 Nov 2008 A large-scale long term study taking up to ten years and involving older American men found that Vitamin E and Vitamin C were no different to placebo in protecting against cancer. The researchers presented their findings at the 7th Annual International Conference on Frontiers in Cancer Prevention Research hosted by the American Association for Cancer Research (AACR) and taking place in National Harbor, Maryland, th