Selenium and Breast Cancer-Reply

In Reply.—  The women in our study live in 11 large, geographically diverse US states, including Texas, a state with a high soil selenium level,¹ and thus their selenium intake is broadly representative of the average intake for US women. The median toenail selenium concentration of the upper quintile in our study was 0.99 μg/g, approximately equal to the value of toenail selenium (0.999 μg/g) among women consuming more than 90 μg/d of selenium supplements in the Nurses' Health Study.²Dr Schrauzer states that our study "actually suggests" a reduced risk of breast cancer in subjects with the highest selenium levels. In fact, the relative risk in the highest quintile of toenail selenium is 1.10, in the opposite direction to that hypothesis. We agree that the confidence interval (0.70 to 1.69) does not exclude a modest protective association, as stated in our original article. Indeed, we are conducting