Vitamin C and cancer. How convincing a connection?

More research is needed to draw definitive conclusions on the relationship between vitamin C intake and cancer, but the following general statements can be made. The effectiveness of megadoses (greater than 1 gm/day) of vitamin C for the cure or prevention of cancer is still unproven; in fact, the safety of megadoses is still in question. Therefore, they are not recommended for the general public at present and, if used at all, should be used under medical supervision. Epidemiologic evidence suggests that vitamin C-rich foods may be beneficial in preventing cancer, and their consumption should be encouraged as a measure to reduce the incidence of cancer. Well-controlled studies should be undertaken to elucidate the relationship between vitamin C and cancer, using both vitamin-containing foods and vitamin C supplements at different intake levels.