Association between Intake and Serum Selenium Levels and Risk Factors of Cardiovascular Disease (Narrative Review)

Background: Selenium (Se) is a necessary elementand is a potent antioxidant adjusting the activity of some enzymes such as glutathione peroxidase (GPx). Selenium metabolism is associated with the biology of heart and its functions, and selenium deficiency is related to cardiovascular pathology. Several studies indicate a relationship between selenium and cardiovascular disease. Objectives: The aim of this study was the investigation of the role of selenium in cardiovascular disease. Methods: We searched the ISI, PubMed, Scopus, and Google Scholar databases for studies that evaluated the association between selenium levels and cardiovascular health and cardiovascular disease. At first, the studies containing the words "selenium ", "cardiovascular disease", "selenium supplementation", "levels of selenium" and "hypertension" were selected. We searched papers using ‘selenium_, ‘selenium supplementation_, ‘selenium deficiency_and, ‘Se_in combination with ‘cardiovascular disease_, ‘hypertension_’, ‘heart disease_’, ‘heart failure_’ as keywords. Results: 17 articles (6 randomized clinical trials and 11 observational studies) were eligible to be included in the current review. Some clinical trials showed that selenium supplementation could decrease the risk factors of cardiovascular disease include lipid profiles and inflammatory markers. Observational studies showed that low selenium concentrations are a risk factor of cardiovascular disease however, this is not definitive. But the presence of normal levels of selenium in the body for antioxidant defense is essential. Conclusion: More clinical trial studies with larger sample size are needed to confirm that selenium is effective in preventing and treatment of cardiovascular disease.