People who take selenium supplements in hopes of boosting their health may be dismayed to learn of new research suggesting that the trace element may actually boost one’s cholesterol level too. The researchers caution those who take selenium to cut back on the supplement in light of these new findings.

The team led by Saverio Stranges at the University of Warwick (UK) measured levels of various blood fats in more than 1,000 otherwise healthy participants, ranging in age from 19 to 64. Those who had increased levels of blood selenium (over 1.20 µmol/liter) also had an increase in total cholesterol levels of 8%. There was also an associated 10% rise in non−HDL cholesterol, which consists of LDL (or “bad”) cholesterol and blood triglycerides.

People who take selenium supplements often do so for the health benefits that they believe to be linked to the element, like antioxidant and anti-cancer properties.

Of those with the highest blood selenium levels, about half said they took supplements. Stranges said that the number of people who supplement their diet with selenium is increasing, which makes the study’s findings all the more revealing on a public health level. Says Stranges, “[selenium] use has spread despite the lack of definitive evidence on selenium supplements efficacy for cancer and other chronic disease prevention. The cholesterol increases we identified may have important implications for public health. In fact, such a difference could translate into a large number of premature deaths from coronary heart disease.”

People who take selenium supplements often do so for the health benefits that they believe to be linked to the element, like antioxidant and anti−cancer properties. Selenium is found in meat, fish, eggs, and some grains, and while selenium deficiency is relatively rare, the mineral can be toxic in large doses (see our full−length article on selenium).

Stranges encourages the public to slow down on selenium supplementation until more research can be devoted to the compound. “We believe that the widespread use of selenium supplements, or of any other strategy that artificially increases selenium status above the level required, is unwarranted at the present time. Further research is needed to examine the full range of health effects of increased selenium, whether beneficial or detrimental."

The article appeared in the November 11th issue of the Journal of Nutrition.