Selenium, vitamin E supplements increase prostate cancer risk


Former Executive Editor, Harvard Health

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When the SELECT trial started in 2001, there were high hopes it would prove that taking vitamin E or selenium could help prevent prostate cancer. The newest results from the trial show just the opposite—that taking selenium or vitamin E can actually increase the odds of developing prostate cancer.

Bottom line: men shouldn’t take selenium or vitamin E as a way to prevent prostate cancer, or anything else for that matter.

“I counsel all of my patients to absolutely avoid any dietary supplements that contain selenium or vitamin E—including multivitamins,” says prostate cancer expert Dr. Marc Garnick, a clinical professor of medicine at Harvard Medical School, an oncologist at Beth Israel Deaconess Medical Center, and editor in chief of Harvard’s Annual Report on Prostate Diseases.

The case against selenium and vitamin E

Studies done in the 1980s and 1990s suggested that vitamin E and selenium each somehow provided protection against prostate cancer. The Selenium and Vitamin E Cancer Prevention Trial (SELECT) was started in 2001 to see if that was true. The 36,000 healthy, middle-aged volunteers were divided into four groups. Each man took two pills a day: 400 international units (IU) of vitamin E plus 200 micrograms of selenium; vitamin E plus a placebo; selenium plus a placebo; or two placebos. Neither the men nor their doctors knew who was taking what.

Although SELECT was supposed to last until 2011, it was stopped three years early because neither vitamin E nor selenium were showing any benefit—and there were hazy warning signs they might be doing some harm.

A new report in the Journal of the National Cancer Institute clarifies the picture. A team of researchers from across the U.S. looked specifically at almost 5,000 of the SELECT volunteers who sent in toenail clippings when they joined the trial. Toenail clippings are a great way to measure how much selenium is in a man’s (or woman’s) body. The new study showed that:

  • Taking vitamin E alone boosted the risk of developing high-grade prostate cancer, but only in men who started the study with low selenium levels.
  • Taking selenium, either alone or in combination with vitamin E, increased the risk of high-grade prostate cancer in men who started the study with high selenium levels, but not in those with low selenium levels.
  • Among men who didn’t take either vitamin E or selenium, those who started the study with high selenium levels were no more likely to have developed prostate cancer than men who started it with low selenium levels. (This means the culprit is added selenium from supplements, not selenium from food.)

“The new data are very troubling, and emphasize that supplements can cause real and tangible harm,” says Dr. Garnick. “Any claims of benefits from dietary supplements must be ignored unless large, controlled, and well-conducted investigations confirm such benefits—which I believe will be a very rare occurrence.”


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  2. Ank sag

    Useful information really appreciated!!

  3. Vito Goldfarb

    I get nauseaus reading this garbage egotistical shit Show the data or shut up!!

  4. Brian

    This stuff changes all the time. Not that long ago Vitamin E was considered the most important vitamin you can take, now many say you shouldn’t take it at all. I think the quality of the supplements matter as well.

  5. Dr. Peterson

    I liked your article about Vitamin E.
    I wanted to ask P.J. Skerrett that what are the symptoms of such type of a cancer ??

  6. Judy

    VB12- 9 tears ago, I started having numbness and tingling in my feet. Numerous neurologists thought it was MS but my MRI’s showed nothing. They didn’t know what was causing my symptoms. 2 years later a dr. took some blood tests and one was for VB12 and my level was 41 (fatal)fortunately, he started me on VB12 injections my level went up, but since then my symptoms have not gotten better, cuz of permanent damage already done. Apparently, my body can’t absorb VB12 orally.No stomach surgeries, diabetes, nothing,
    I just can’t absorb it orally. But my question is, is there anything I can do or take to improve my balance and walking?

  7. Sexy Dancer

    This is not new. I am just a laymen and I know that synthetic vitamin E is not the one recommended by Naturopaths and Nutrition experts. If you are going to do a study why not use the forms commonly recommended? But then that would be too expensive wouldn’t it? And also you would not want to have the possibility of good results

  8. reeveta

    I think Your Blog is so interested and special for best suplements


    Thank sticking to all the information

  10. Patrick

    Not a propper study used the wrong form of E and a toxic form of Selenium. Bolox study sorry but its true.

  11. Patrick

    This is not new. I am just a laymen and I know that synthetic vitamin E is not the one recommended by Naturopaths and Nutrition experts. If you are going to do a study why not use the forms commonly recommended? But then that would be too expensive wouldn’t it? And also you would not want to have the possibility of good results.

    If vitamins and herbs are so bad I should have died years ago. And by the way I have been taking 200mcg per day of Selenium the selenomethionine form for 10 years and also 500IU of Vitamin E in the D-alpha tocopheral (natural E) also for at least 15 years. I am alive and well. My hair line was started to recede and a practiioner advised me to take the selenium and Zinc and the hair stopped falling out.

    If Vitamins were going to kill me I should have been dead years ago.

    • Vito Goldfarb

      Thank you Patrick I agree 100% I supplement also and have been for many years with no problems My Personal phsyician knows nothing wake up mother fuckers!!!!

  12. Dr H Hamdani

    I do believe that we should not encourage any medicines, even supplements without any real indications, even if there is no side effects. But as the recent researches were showing evidence that Selenium reduces the chances of prostate risk, and tomato sauce is rich in Selenium, I started advising my high risk patients to include tomato sauce in their daily diet. new concepts and research conclusions are changing so fast, it is really confusing.

    • Vince Miraglia

      Hopefully you recommended sauce made from fresh tomatoes. Since processing and added salt and sugars may reduce or even eliminate and benefit from the tomato.What about the effect from the can lining I believe questions have been raised about BPA…..

  13. Home Water Purifying Systems

    Thanks for posting such an informative news with us. I really appreciate your effort and consciousness towards health. It is very essential to know the side effects of pills and drugs take by the peoples.
    Pills like vitamin E and selenium which is consider by people as one of the source to cure cancer now have side effect. So, an awareness about this should be give to the patients.

  14. Fitness Holidays

    Whether it is high quality supplement or low quality supplements being tested we should still get as much of our nutritional requirements from natural sources. Such as sunflowers.

  15. seo company india

    i read your article,Yes,you read correctly. it is very good thanks for information. thanks

  16. Sean

    It seems that most studies of “supplements” end up showing at best, no positive outcomes, and, at worst, an actual increase in risk to participants receiving the “treatment”.
    While it is debatable that some studies may have used “better” or “worse” forms, isomers, “chelations”, etc. of vitamins, fish oils, minerals, etc., etc., it certainly seems to be the case that, on the balance of the evidence, supplements do nothing (good) for people.
    I find it very interesting that instead of rationally accepting this, there is almost invariably an attempt to turn this into a “Big Pharma” conspiracy theory…
    Be it “Big Pharma” or “Big Supplements” (ingredients usually manufactured by big pharma companies, BTW…) the concept of continually ADDING more and more things to the diet in hopes of compensating for the already ludicrously excessive consumption of salt, sugar, and fat and the deficiency of natural, whole foods stinks of consumerism-run-amok (!). Can we really just buy our way to health and happiness by eating more and more manufactured “products”?
    Buying and eating more crap (supplements and drugs included) is not the sane, rational route to health. Eating whole foods, eating only the calories sufficient to maintain body weight (i.e. less than most people currently consume), and avoiding any and all fads that say to “EAT MORE!” of anything concocted by food manufacturers, drug manufacturers, and supplement manufacturers is the truly sensible (and oddly radical?) approach to promoting the best health for the most people on this planet.

  17. Paul

    In the interest of full disclosure, I wonder if the big Pharmacuticals funded any parts of these studies? They have a vested interest in steering people away from alternative remedies,back to the poison they sell. We all know you can’t patent a natural substance, like vit. E, so they can’t make any money from it. Show me one prostate cancer remedy, coming from Big Pharma, that actually works, without leaving the patient an invalid for the rest of his life?

  18. Ann

    Thanks for your article, it was very informative and exhaustive. The committee EXCLUDED the forms of vitamin E and selenium previously shown to be effective. This should be publicized more to bring to the attention of common people

  19. seo company india

    i read your article,Yes, you read correctly. The committee EXCLUDED the forms of vitamin E and selenium previously shown to be effective. it is very good thanks for information.

  20. Thomas Anderson

    Comment above is right on. Cheapest form of vitamin E has been used in these studies, a form that is actually toxic. When will they ever learn !!!

  21. P. W. Fisher

    The SELECT study demonstrated only that a synthetic form of one of the eight forms of vitamin E and a form of selenium different than the form of selenium that had previously shown significant reduction of prostate cancer showed no reduction in the SELECT study.

    SELECT is a phase III randomized, placebo-controlled trial of selenium (200 microg/day from L-selenomethionine) and/or vitamin E (400 IU/day of all-rac–tocopheryl acetate) supplementation for a planned minimum of 7 years (maximum of 12 years) for prostate cancer prevention.

    The panel of investigators reconsidered the possibility of using the yeast form of selenium because results with yeast would compare directly with the results of the NPC study, which provided the major rationale for selenium in SELECT. Therefore, in July and October 2000, an expanded panel of selenium experts reexamined the decision to use selenomethionine and reevaluated the issue of whether high-selenium yeast may be a preferable source of selenium. However, after reviewing new evidence that indicated substantial batch-to-batch variations in both the presence and relative levels of specific organoselenium compounds in samples of NPC yeast the panel reaffirmed the original decision to use selenomethionine at 200 microg/day.

    Compared with the selenium formulation considerations, the decision to use vitamin E in the form of all rac–tocopheryl acetate was made relatively easily, given both its activity in the ATBC Study and its absorption and metabolism in humans. Supplements made from naturally occurring RRR–tocopherol that have approximately twice the biologic activity of synthetic forms exist, but because there have been no controlled trials of this form in disease prevention, RRR–tocopherol was excluded as a potential choice for SELECT.

    (See Designing the Selenium and Vitamin E Cancer Prevention Trial (SELECT) JNCI Journal of the National Cancer Institute 2005 97(2):94-102; doi:10.1093/jnci/dji009 )

    Yes, you read correctly. The committee EXCLUDED the forms of vitamin E and selenium previously shown to be effective.

    • Trig

      The best form is neither the racemic crud made by BASF or
      the one isomer rrr-alpha tocopherol but rather high gamma
      and delta forms are better. Also the most promising form is the higher gamma tocotrienols. There the issue of competitive absorption such that taking high dose synthetic which due to its unnatural molecular structure fails to bind to the binding protein and thus thus a short biological half life plus the synthetic and even the all rrr-alpha form displaces the beta, gamma and delta forms. The body clearly
      has uses for the beta, gamma and delta forms. They occur in
      nature and this type of biochemistry is highly conserved
      through the whole tree of life.
      So if you supplement, I say consider a high gamma T be it
      tocopherol or tocotrienol.

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