Selenium May Not Reduce the Risk for Heart Disease

A new study suggests that selenium supplementation may not reduce the risk of heart disease.

Selenium is an essential trace mineral found in soil, water and some foods. It is a component of the amino acids cysteine and methionine. Selenium is required for functioning of the body's antioxidant enzymes and for cell growth and survival.

The presence of selenium in locally grown food and selenium levels in human populations reflects the selenium levels in local soil. The selenium content in food is influenced by geographical location, seasonal changes, protein content and food processing. Periodic monitoring of selenium levels in soil and food is necessary. Selenium supplements may benefit people living in regions with very low environmental levels of selenium.

In a recent study, researchers conducted a comprehensive literature search for well-designed clinical trials evaluating the effects of selenium supplementation on heart disease, death, diabetes and changes in heart disease risk. Twelve studies evaluating 19,715 individuals were ultimately identified for inclusion.

The researchers found that selenium supplementation may not have a significant effect on the risk for death, death caused by heart disease, non-fatal heart disease-related events and all heart disease-related effects. Adverse effects related to selenium supplementation included hair loss and dermatitis. The authors noted that selenium supplementation reduced total cholesterol; however, the reductions were not significant. Furthermore, supplementation was linked to a slight increased risk for diabetes; however, this result was also not significant.

The authors concluded that there is a lack of supportive evidence to suggest that selenium supplementation may reduce the risk for heart disease. Further research is warranted.

In addition to selenium, several other integrative therapies have been studied for their potential to reduce heart disease risk. Early studies in animals and humans suggest that diets containing chia seed may decrease risk factors for cardiovascular disease (CVD). Evidence suggests that the benefits of Salba® in humans are similar to those of other whole grains. Further study is needed.

For more information about integrative therapies with evidence of benefit of heart disease prevention, please visit Natural Standard's Comparative Effectiveness Database. 

For more information about selenium, please visit Natural Standard's Foods, Herbs & Supplements Database.

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References

1. Natural Standard: The Authority on Integrative Medicine. 
   
2. Rees K, Hartley L, Day C, et al. Selenium supplementation for the primary prevention of cardiovascular disease. Cochrane Database of Systematic Reviews 2013, Issue 1. Art. No.: CD009671. DOI: 10.1002/14651858.CD009671.pub2.