Can vitamin C cure or prevent breast cancer?

High doses of vitamin C (ascorbic acid) have been proposed as a cure for various cancers, including breast cancer. Vitamin C is an essential micronutrient for human health. Relatively high consumption of vitamin C (eg, food consumption) were associated with low risk of childhood leukemia, as well as oral, skin, stomach, pancreas, colon, endometrial and prostate cancer. Excessive vitamin C was also associated with a lower risk of certain cancers, including bladder cancer in men and colon cancer in women.

The case of vitamin C is based in part on the observation that patients with breast cancer tend to have low blood levels of antioxidants compared to healthy women, indicating that patients have the antioxidant defenses of the body is exhausted and are vulnerable to oxidative damage that could further promote breast cancer. Laboratory studies have shown that concentrations of vitamin C in the growth of various human cells slows breast cancer. We are not aware of the academic studies that a survival advantage for women treated with high doses of vitamin C. Based on data available to show that vitamin C can then feeding against breast cancer, protect supplementation with relatively high doses of vitamin C can not be beneficial for cancer patients or survivors. In fact, the evidence suggests that supplements of this type can actually promote cancer.

Most patients with breast cancer survivors and those at high risk in a good position to get their vitamin C through their diet (see the list of food sources below). Supplementation with vitamin C is not necessary and treatment with high doses of vitamin C would be counterproductive. The vitamin C supplements should not be used during chemotherapy.

Vitamin C appears to work synergistically with other nutrients in the diet to fight against cancer. On the other hand, high doses of vitamin C off the anti-cancer effects of certain micronutrients known to have a protective effect against breast cancer.