High selenium intake may have a protective effect against bladder cancer, mainly among women, according to a recent meta-analysis.

The meta-analysis, led by Núria Malats, MD, PhD, of the Spanish National Cancer Research Centre in Madrid and colleagues used data from seven published epidemiologic studies (three case-control, three nested case-control, and one case-cohort) published before 2010. The studies included a total of 1,910 cases and 17,339 controls or cohort members.

Overall, compared with the lowest intake of selenium, the highest intake was associated with a 39% decreased risk of bladder cancer. When the investigators stratified subjects by gender, only women had a significantly decreased risk of bladder cancer associated with selenium. Women with the highest selenium intake had a 45% decreased risk compared with those who had the lowest intake, according to a report in Cancer Epidmiology, Biomarkers & Prevention (2010;19:2407-2415). This protective effect in women may result from gender-specific differences in selenium’s accumulation and excretion, the authors explained.

“Although our results suggest a beneficial effect of high selenium intake for bladder cancer risk, more studies are needed to confirm these findings before an enforcement of high selenium intake is recommended,” Dr. Malats said.