Fact ??

Studies have yet to find any precise connections between antioxidants and cancer or any other disease.

Unfortunately it has not been proven so perhaps eat a well balanced diet.
There are  times that there is a slightly higher risk of dying in people who were given extra high doses of Vitamin E on a daily basis or higher risk of lung cancer such as  may occur when given extra high doses of beta carotene. Vitamin C doesn't seem to raise or lower either risk. As for most vitamins: they are harmless in low doses.