Vitamin C supplements seem to stymie chemo

September 30, 2008 2:26:57 PM PDT
Cancer patients taking vitamin C for their health may be unknowingly hurting their treatment therapy. Chemotherapy drugs killed 30 percent to 70 percent fewer tumor cells than usual when vitamin c was involved.

A study in the journal Cancer Research found vitamin C supplements may undercut the effectiveness of cancer drugs, including Gleevec.

The study found, when mice got vitamin C supplements two hours before chemotherapy, the tumors grew more quickly.

Researchers tested five common chemo drugs. They say the vitamin C didn't neutralize the effects but rather blunted the effects of the drugs.