Many people believe that dietary supplements are good for health and don’t think twice before buying bottles of expensive vitamin or mineral supplements. But what you may not know is that some supplements provide much more than the needed dose of micronutrients and this can actually increase your risk of cancer. So it would be a good idea to check the label of your multivitamin.
Recent studies suggest that multivitamins may not be all that they are cracked up to be. Especially Vitamin E and selenium supplements are now suspected to increase the risk of high-grade prostate cancer.
Selenium, Vitamin E and prostate cancer risk
Selenium is a chemical element which is naturally found in sea foods, dairy products and cereals. It is an essential nutrient for humans and plays important role in DNA synthesis, reproduction and thyroid hormone regulation. It also serves the function of protecting from internal infections and oxidative damage. Vitamin E is found in nuts, seeds, green leafy vegetables and cereals and is responsible for good skin and hair. Both selenium and vitamin E are antioxidants.
This new multi-center study examined almost 5000 men. This trial was popularly called SELECT (Selenium and Vitamin E Cancer Prevention Trial). These men were assigned to two groups randomly- one group had to take high doses of selenium and vitamin E supplements while the other group took a placebo. The study was conducted with the aim of determining if taking high doses of selenium and vitamin E could reduce prostate cancer risk.
Before these men started taking supplements, researchers checked and recorded the amount of selenium present in their toenails as selenium content in your body is accurately reflected in your nails. This was done because the general belief at that time was that men who already had sufficient selenium would not derive any benefit from selenium supplements.
The trial had to be stopped in 2008, much before its stipulated time of 12 years, because no protective effect of selenium was evident. Instead an increased risk because of vitamin E was found in these men.
Results of this study showed that men with low selenium levels at the beginning of the study actually did not benefit from selenium supplements while men who had high selenium levels right at the beginning now had a 91% higher risk of prostate cancer. The level of selenium in these men had reached toxic limits. It was also found that vitamin E increased prostate cancer risk, even for those men who had low selenium levels.
The men stopped using supplements but were still followed for some time and it was found that men who took vitamin E had a 17% higher prostate cancer risk. This was true for even those men who had low selenium levels at the beginning of the study.
Should you give up your vitamins?
The bottom-line is that the risk largely depends upon the selenium levels in the man’s body before he begins taking supplements. Though there are no obvious risks from a regular multivitamin, single supplements which provide a high dose of a single nutrient could bring unexpected harmful results.
There is an optimal level recommended for most vitamins and minerals which you can obtain from a balanced diet. Supplements should be taken only if and as advised by a doctor. It is important to avoid diet fads which make you miss out on natural nutrients which can help build your immunity levels.
Even if you are taking just a standard multivitamin, which has no proven risk yet, you must remember to keep your intake within recommended limits as higher or lower intake of micronutrients could pose grave health problems in the future.
Check with your Chicago Cancer Treatment Center of America (CTCA) to learn more about multivitamins and cancer risk. CTCA has been a pioneer in providing the best cancer related information, treatment and patient care. Not surprisingly, CTCA at Midwestern regional Medical Center in Chicago was recognized as one of the best hospitals for providing finest patient experience.