Vitamin C Interferes with Anti-Cancer Drugs

Study finds vitamin C interferes with anti-cancer drugs.

Laboratory studies have found that vitamin C may interfere with the effectiveness of five anti-cancer drugs. First, the researchers gave a vitamin C product to cancer cells that were treated with chemotherapy and found that the 30% to 70% fewer cancer cells were killed. Then they injected mice with cancer cells, administered chemotherapy, and found that cells grew into tumors much faster in the mice that received pre-treatment vitamin C. The researchers warned that although results in animals are not necessarily applicable to humans, vitamin C supplementation during cancer treatment may interfere with the effect of chemotherapy. [Heaney ML and others. Vitamin C antagonizes the cytotoxic effects of antineoplastic drugs. Cancer Research 68:8031-8038, 2008]