Saturday Quack – Careful with Selenium Supplements

The use of selenium dietary supplements has risen recently, largely due to the (erroneous) belief that the mineral can reduce the risk of cancer and other diseases.  However, a small 2007 US study has shown that selenium supplements are linked with an increased risk of developing type 2 diabetes.  Now a study from UK, where selenium blood levels are usually lower, has been reported in the Journal of Nutrition; it shows that too much selenium can possibly be harmful. 

Plasma selenium levels were measured along with blood lipid profiles in over 1,000 British adults aged 16 to 64.  In those subjects with higher plasma selenium there was an average 10% increase in total cholesterol levels.  And there was a 10% increase in non-HDL-cholesterol - that really means the bad, LDL-cholesterol.

As the researchers say, “These findings raise additional concern about potential adverse cardio-metabolic effects of high selenium status”.  Until there is evidence demonstrating conclusive benefits from selenium supplements, it’s probably better (and cheaper) not to take them.