Researchers have found that high levels of selenium are associated with increased cholesterol. They discovered that too much of the essential mineral selenium in the diet can increase cholesterol by almost 10%.
High levels of cholesterol in the blood can increase the risk of heart disease. The body needs some cholesterol to work properly, but when there is too much cholesterol in the blood, it can stick to the artery walls.
Cholesterol can be lowered by exercising more and eating more fruits and vegetables. Selenium is a trace essential mineral with anti-oxidant properties that the body naturally absorbs from foods such as vegetables, meat and seafood. When the body absorbs too much selenium through taking selenium supplements the balance might be altered and it can have adverse affects.
Image: Model of cholesterol molecule.
The researchers examined the association of levels of selenium in the blood (plasma selenium) concentrations with fats in the blood in 1042 participants aged 19-64 in the 2000-2001 UK National Diet and Nutrition Survey. All participants were interviewed face-to-face to assess lifestyle factors such as diet and drinking habits. Blood samples were then taken for analysis.
They found in those participants with higher plasma selenium (more than 1.20 µmol/L) there was an average total cholesterol level increase of 8% (0.39 mmol/L (i.e. 15.1 mg/dL). Researchers also noted a 10% increase in non-HDL cholesterol levels (lipoproteins within your total cholesterol that can help predict the risk of someone suffering a heart attack or chest pain). Of the participants with the highest selenium levels, 48.2% admitted they regularly took dietary supplements.
Research team leader Dr Saverio Stranges said although high selenium levels were not exclusively caused by people taking dietary supplements, the results of the study were concerning because the use of selenium dietary supplements had risen considerably in the UK in recent years. He said this was largely due to the perception that selenium can reduce the risk of cancer and other diseases.
He said: “This use has spread despite a lack of definitive evidence on selenium supplements efficacy for cancer and other chronic disease prevention. The cholesterol increases we have 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.
“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.”
References:
1. Saverio Stranges, et al. Higher Selenium Status is Associated with Adverse Blood Lipid Profile in British Adults. Journal of Nutrition, Nov 11, 2009. doi:10.3945/jn.109.111252.
