Cancer Care Blog #2Cancer Blogs, Dr. Diane Hastings — By Dr. Hastings on May 5, 2009 at 3:23 pm
A study published in April 2007 in the Journal of Supportive Oncology found that 52% of cancer patients take dietary supplements and 42% consume herbal supplements.
The use of herbal supplements was more common among patients who were experiencing pain or fatigue or who had a higher cancer stage. Yet, the government does not test most supplements for safety or for effectiveness.
Moreover, some over the counter supplements that might be helpful in preventing cancer may actually complicate, or interfere with your treatment.
To know for certain whether a supplement will help to cure or prevent cancer, a double-blind, placebo controlled study is necessary.
Most of the claims you might read about vitamins or herbs are based on a different type of study, an observational study. The problem with this type of study is that the vitamin tested may be only one possible explanation for the outcome of the study.
For example, in the May Nutrition Action Health letter, David Shardt discusses whether three expensive supplements are truly worth the cost. Coenzyme Q10 has been promoted to improve survival in breast cancer treatment. The study behind that claim was done in the 1990’s and included only 32 women.
The women took many different supplements each day for a year and a half, including Coenzyme Q10. Five of these women had tumor remission at the end of the study. Is it fair to give the credit for that positive outcome to Coenzyme Q10? It might have been any one of the many vitamins and minerals that these women consumed. Perhaps it wasn’t even a factor in the study, perhaps the women who volunteered for this study were more likely to eat good sources of protein or plenty of fresh, local vegetables or do yoga. Sadly, many of the claims made about supplements and cancer are based on similar types of research.
During cancer treatment, it can be difficult to resist the claims made for products that are touted to improve survival.
Some people feel that it can’t hurt so I might as well try taking a supplement and see how I feel. Unfortunately, it ‘s possible that consuming supplements during treatment can hurt. Although the F.D.A. monitors dietary supplements as “ingestible nonfood substances” (New York Times, March 4, 2009). They are powerless to remove supplements that they find to be harmful. Instead they rely on the producers to voluntarily remove products that the FDA has reported to be harmful.
The companies are not always so obliging, of 69 weight loss supplements that the FDA found to be potentially dangerous, only three were taken off the market in response to the FDA concern.
If you are considering adding a supplement during your treatment, seek advice or do a little internet research before you act. Look into the source of the claim for that supplement, who paid for the study supporting the claim? Was there a control group or a placebo used in the actual study?
If you are already consuming a supplement during treatment, let your health care provider know so that drug interactions and safety can be checked for you. As reports become available, Cancer Care blog will also be evaluating common supplements used to prevent or cure cancer.