Variations in selenium metabolism in males and females

Abstract

Selenium elicits its effects on human health mainly in the form of selenoproteins, even though some selenocompound-specific effects have been described. The physiological roles of certain selenoproteins have been characterized in transgenic mice, and epidemiological analyses have indicated associations of selenoprotein genotypes with common pathologies. Supplementation studies yielded promising results indicating that selenium can reduce cancer risk, autoimmune disease, subfertility, or mortality risk in severe illness. General conclusions are drawn and discussed vividly in science, health politics, and elsewhere. But studies in experimental rodents indicate that selenium metabolism and selenoprotein expression patterns differ between the sexes. Similarly, the selenium-dependent reduction of cancer risk, subfertility, or mortality in sepsis is mainly observed in males but not in females. Selenium-dependent health effects in thyroiditis are described in females only, and associations of selenium status and goiter, thyroid nodules or cardiovascular disease are sexually dimorphic. Even the major side effect, i.e., increased diabetes risk, appears to be male-specific. Therefore, selenium metabolism and selenium health effects differ between females and males, and generalizations should not be made across the sexes.