A new study shows that high-dose vitamin C may help kill pancreatic cancer cells, but only when given intravenously. Oral vitamin C cannot reach the high blood levels needed for an anti-cancer effect. In laboratory tests, intravenous-level vitamin C significantly reduced the survival of multiple pancreatic cancer cell lines.
Researchers also found that iron plays a complex role. When iron and vitamin C were given at the same time, the cancer-killing effect was reduced. Giving iron before vitamin C produced mixed results—helping some cancer cells respond better while making others more resistant, especially those with common KRAS mutations.
The study found that vitamin C works by triggering ferroptosis, a form of cell death linked to iron and oxidative damage, rather than traditional apoptosis. Tumors with higher levels of the TfR1 protein may respond better to treatment. The findings suggest careful monitoring of iron levels is important, while high-dose vitamin C remains generally safe for most patients.