Early clinical studies showed that high-dose vitamin C, given by intravenous and oral routes, may improve symptoms and prolong life in patients with terminal cancer; however, double-blind placebo-controlled studies of oral vitamin C therapy showed no benefit. Since then, several cases of unexpectedly long suvival of metastatic cancer patients who received only Vitamin C treatments have revived an interest in this drug. This remains an intensely controversial topic but at this time Vitamin C therapy of any kind remains investigational and not medically necessary.
Padayatty, Sebastian J., Riordan, Hugh D., Hewitt, Stephen M., Katz, Arie, Hoffer, L. John, Levine, Mark
Intravenously administered vitamin C as cancer therapy: three cases
CMAJ 2006 174: 937-942
S. OHNO, Y. OHNO, N. SUZUKI, G.-I. SOMA, and M. INOUE
High-dose Vitamin C (Ascorbic Acid) Therapy in the Treatment of Patients with Advanced Cancer
Anticancer Res, March 1, 2009; 29(3): 809 – 815.
B. Frei, S. Lawson, M. Levine, Q. Chen, and M. G. Espey
Reply to Borst: Randomized clinical trials of high-dose intravenous vitamin C in cancer patients are warranted
PNAS, December 2, 2008; 105(48): E96 – E96.
Mega-dose vitamin C as therapy for human cancer?
PNAS, December 2, 2008; 105(48): E95 – E95.