High doses of intravenous vitamin C help to treat cancer by slowing the growth and spread of prostate, pancreatic, colon, liver and other types of cancer cells, reports the National Cancer Institute. The same dose of intravenously administered vitamin C yields higher blood vitamin C levels than oral administration.
Vitamin C?s anticancer effect in different types of cancer cells involves a chemical reaction that creates hydrogen peroxide, which may cause cancer cells to die. Human studies using high-dose intravenous vitamin C in cancer patients have demonstrated improved quality of life as well as improvements in mental, physical and emotional functions, fatigue, nausea and vomiting, appetite loss and pain. Additionally, animal studies have shown that high-dose vitamin C treatment blocks tumor growth in some types of liver, pancreatic, prostate and ovarian cancers, malignant mesothelioma and sarcoma, according to the National Cancer Institute.
Intravenous high-dose ascorbic acid has caused few side effects in clinical trials, and scientists have studied high-dose vitamin C as a treatment for patients with cancer since the 1970s. The U.S. Food and Drug Administration has not approved the use of intravenous high-dose vitamin C as a cancer treatment, states the National Cancer Institute.
The basis for the claim that vitamin C is useful for a cancer treatment is a study suggesting that cancer is a disease involving changes in connective tissue caused by a lack of vitamin C. Scientists then proposed potentially treating cancer with high-doses of ascorbic acid to help build resistance to disease and infection, reports the National Cancer Institute.