
- With Mayo Clinic medical oncologist
Timothy J. Moynihan, M.D.
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Timothy J. Moynihan, M.D.
Timothy Moynihan, M.D.
"As a practicing medical oncologist, I meet with patients and families every day to help manage their course through this disease called cancer. This experience provides unique insight into the needs of cancer patients, their families and loved ones and brings into sharp focus the need for reliable information to be readily available in terms that can be easily understood." — Dr. Timothy Moynihan
Dr. Timothy Moynihan believes that providing consumers with accurate, timely information on the broad, complex topic of cancer is the biggest challenge facing medical websites. As the guiding force behind our cancer content, he makes sure Mayo Clinic meets the test.
Dr. Moynihan, born in Las Vegas, N.M., and raised in Denver, is a consultant in medical oncology at Mayo Clinic and an associate professor at Mayo Clinic College of Medicine, Rochester, Minn. He's board certified in internal medicine, medical oncology, and hospice and palliative care medicine.
He did his medical oncology training at Johns Hopkins Hospital in Baltimore, and then went on to the University of Minnesota and St. Paul Regions Medical Center for seven years before moving to Mayo Clinic in 1999. Dr. Moynihan is medical director of the Mayo Clinic hospice.
Dr. Moynihan serves as the education chair for the Department of Oncology and the fellowship program director. Four times he has been selected as Teacher of the Year in medical oncology and elected to the Teacher of the Year Hall of Fame.
Past honors include distinguished clinical teacher at the University of Minnesota Medical School, best internist at the Medical College of Wisconsin and recipient of the Upjohn Achievement Award for Excellence in Medicine. Dr. Moynihan serves on several national committees for the American Society of Clinical Oncology.
"The Internet provides a ready source of information on a wide range of topics of interest to those affected by cancer," Dr. Moynihan says. "The difficulty is trying to decide which sites provide reputable information and which information is relevant to each individual patient. The long history and tradition of excellence associated with Mayo Clinic assures you that information provided will be reliable, up-to-date and comprehensive."
Risk factors (1)
- Cellphones and cancer: What's the risk?
Tests and diagnosis (3)
- Small cell, large cell cancer: What this means
- Tumor vs. cyst: What's the difference?
- Atypical cells: Are they cancer?
Causes (1)
- Night shift and cancer: Any connection?
Treatments and drugs (6)
- What is compassionate use of experimental drugs?
- Magic mouthwash: Effective for chemotherapy mouth sores?
- After a flood, are food and medicine safe to use?
- see all in Treatments and drugs
Alternative medicine (2)
- Curcumin: Can it slow cancer growth?
- High-dose vitamin C: Can it kill cancer cells?
Question
High-dose vitamin C: Can it kill cancer cells?
I've heard that vitamin C might be an alternative cancer treatment. What can you tell me about it?
Answer
from Timothy J. Moynihan, M.D.
The use of vitamin C in alternative cancer treatment isn't new. Proponents claim that large doses of vitamin C are toxic to cancer cells. However, there is no reliable evidence gathered in human studies to support this theory.
Studies in the 1970s first suggested that large doses of supplemental vitamin C might be of some benefit in the treatment of cancer. But these studies were later found to have serious flaws. Subsequent well-designed, randomized, controlled trials of vitamin C and cancer found no such treatment benefit.
More recently, vitamin C given intravenously (IV) has been touted to have different effects than vitamin C taken orally. This has prompted renewed interest in the use of IV vitamin C as a cancer therapy. However, there is still no evidence that vitamin C has any effect on cancer. Until clinical trials are completed, it's premature to determine what role, if any, IV vitamin C may play in the treatment of cancer.
Next questionCellphones and cancer: What's the risk?
- Cabanillas F. Vitamin C and cancer: What can we conclude — 1,609 patients and 33 years later? Puerto Rico Health Sciences Journal. 2010;29:215.
- Vitamin C (ascorbic acid). Natural Medicines Comprehensive Database. http://naturaldatabase.therapeuticresearch.com/home.aspx?cs=mayo&AspxAutoDetectCookieSupport=1. Accessed March 2, 2011.
- Verrax J, et al. The controversial place of vitamin C in cancer treatment. Biochemical Pharmacology. 2008;76:1644.

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