Over one million people were involved in the studies, which included six random, placebo-controlled trials (RCTs).
A new Cochrane Review analyzing 55 studies on selenium levels and cancer development says that a link cannot be made for selenium and cancer prevention. Over one million people were involved in the studies, which included six random, placebo-controlled trials (RCTs).
Results indicated that higher selenium levels were linked to lower frequencies of some cancers (e.g., bladder or prostate cancer), but not others (e.g., breast cancer).
Of the six RCTs, trials believed to provide the “most reliable results” found that organic selenium did not decrease prostate cancer risk in males, but did increase risk of non-melanoma skin cancer in men and women.
Shaky results from the available data left Cochrane researchers to conclude that there is currently no convincing evidence for selenium supplementation and reduced cancer risk. Lifestyle factors, including diet and type of job, could not be ruled out.