Vitamin E Increases Cancer Risk?

Numerous studies have investigated the possible role of vitamin E in cancer prevention.  Early studies cast a favorable light on preventing prostate as well as other forms of cancer.  These early findings were so positive that The National Cancer Institute funded the Selenium and Vitamin E Cancer Prevention Trial (SELECT).  The trial was a double blind randomized placebo controlled clinical trial with a target enrollment of over 34,000 men 50 years of age or older.  This recruitment began in 2001 with the goal of following the groups until 2013. There were four study arms which included:  vitamin E, selenium, both E and selenium supplementation, and placebo.  

In 2009 a followup report indicated that, at that point in the study, there was no evidence that vitamin E with selenium prevented prostate cancer.  The most recent report provided in the October 2011 issue of the Journal of the American Medical Association provides unexpected and somewhat astounding findings:

“Dietary supplementation with vitamin E significantly increased the risk of prostate cancer among healthy men.” 

Vitamin E has historically been thought to help with many health conditions. Unlike other vitamins and many minerals there was little reason for considering it a potentially harmful agent.  What we often believe to be “natural” and health promoting may in fact be harmful to our patients.  These findings underscore the need for clinicians to keep current with the published research.  Naturally, we do not want to place too much weight in a single study but with the strength of the SELECT study design and the significant differences between the groups, the conclusions can’t be ignored.