ResearchBlogging.orgIn a recent study, 35,533 prostate cancer-free men in a higher risk age group for prostate cancer in the US, Canada and Puerto Rico were given various treatments of Vitamin E, selenium, and placebo in order to see if claims that Vitamin E and/or Vitamin E with selenium were effective in reducing prostate cancer risk.

  • 8752 received selenium alone – 575 developed prostate cancer.
  • 8737 received Vitamin E alone – 620 developed prostate cancer.
  • 8702 received both – 555 developed prostate cancer.
  • 8696 placebo – 529 developed prostate cancer.

It turns out that Vitamin E may increase the risk of prostate cancer. Using Vitamin E and/or Selenium to reduce risk of prostate cancer in men old enough to have a higher risk of this disease is ineffective.

Klein, E., Thompson, I., Tangen, C., Crowley, J., Lucia, M., Goodman, P., Minasian, L., Ford, L., Parnes, H., Gaziano, J., Karp, D., Lieber, M., Walther, P., Klotz, L., Parsons, J., Chin, J., Darke, A., Lippman, S., Goodman, G., Meyskens, F., & Baker, L. (2011). Vitamin E and the Risk of Prostate Cancer: The Selenium and Vitamin E Cancer Prevention Trial (SELECT) JAMA: The Journal of the American Medical Association, 306 (14), 1549-1556 DOI: 10.1001/jama.2011.1437

Comments

  1. #1 Ian
    November 2, 2011

    Stop taking the vitamin E…but get yourself some placebo :)

  2. #2 Jim
    November 2, 2011

    Prostate = an organ in the human body
    Prostrate = lying flat on the ground

  3. #3 Greg Laden
    November 2, 2011

    Hahaha. Damn you autocorrect!!! Thanks for the catch.

  4. #4 Jon Tomas
    November 2, 2011

    The overriding concern with studies of vitamin E efficacy (or lack thereof) is the failure to consider, or incorporate, the various isomers of tocopherol (to say nothing of tocotrienol) available in the human diet. Use of high dose alpha-tocopherol supplements, for instance, selectively depletes humans of gamma-tocopherol, a tocopherol with activity distinct from that of the alpha isomer. An equally likely scenario to “Vitamin E increases the risk for prostate cancer” would be “preferential supplementation with alpha tocopherol, sans regard for balanced intake with respect to the other isomers of tocopherol, may result in a physiological environment more conducive to the development of prostate tumors”. The role of vitamin E in human health is far more complicated than the “if…then” scenario spun by the popular press, or even by those clinical researchers who cannot, or will not, control for such factors in the course of their investigations.

  5. #5 Art
    November 3, 2011

    “Stop taking the vitamin E…but get yourself some placebo :)”

    Do homeopathic placebos work better than the organically grown herbal placebo teas? If I’m going to use a placebo I want only the best.

    I want a large double-blind, study of the relative effectiveness of various placebos.

  6. #6 dhogaza
    November 3, 2011

    Do homeopathic placebos work better than the organically grown herbal placebo teas?

    Well, they should be cheaper, just buy some distilled water and label it …

  7. #7 Dunc
    November 3, 2011

    I want a large double-blind, study of the relative effectiveness of various placebos.

    Some work has been done. The result depends on what you’re trying to treat and the cultural expectations of the patient, but yes, there can be a significant difference in effectiveness between different kinds of placebos. For example, intravenous placebos are usually more effective than oral placebos, red pills make better stimulant placebos and green pills make better sedative placebos. (In European tests, at least. Cultures with different colour associations would probably fare differently.)

  8. #8 GregFromCanada
    November 3, 2011

    How many in around 8700 men who don’t take VE, Sel. or placebo normally get prostate cancer? I understand that the placebo group is the control, but it would be good to have the numbers for normal occurrences along with the rest.

  9. #9 Jeff
    November 3, 2011

    @Jon Tomas: Your argument was well stated. Another factor was the kind of vitamin E used in this study – synthetic DL-Alpha Tocopherol, which has much less biological activity than natural vitamin E.

    Fortunately there have been vitamin E studies like this one which stress the importance of combining all the various forms of vitamin E. Unfortunately these studies are ignored by most media outlets.

  10. #10 jmdesp
    November 3, 2011

    Those are some very wide variation in the results.

    Of course +17% cancers in the Vitamin E case is very worrying but when you see that Vitamin E together with selenium is only +5%, whilst selenium alone is +8,7%, you conclude that either selenium somehow quite significantly reduces the bad effect of Vitamin E, despite having no positive effect alone, or that “something” in this study caused a abnormally large dispersions of results which makes it very hard to get any statistically significant result out of it.