Introduction
Selenium is a compound found in grains, meat, and nuts. The body uses selenium to make antioxidants that help fight damage to cells. Selenium has been used to improve thyroid and heart health. It has also been used to promote general wellness and help the body fight off illness. Selenium can be taken as a pill or tincture. It can also be injected into the bloodstream by a healthcare provider.
Dosages
200 micrograms once daily
What Research Shows
Likely Effective
- Metabolic syndrome —likely to improve insulin sensitivity; but unlikely to improve blood fat and blood glucose levels I1
May Be Effective
- Critical illness—may lower mortality F1-F4
Unlikely to Be Effective
- Cardiovascular disease —unlikely to prevent disease C1
- Enhancing Mental Function —unlikely to improve cognitive health D1
- Critical illness—may lower mortality F1-F4
- HIV Infection —unlikely to have benefit G3
- Lipid profile —unlikely to have a positive effect H1
Not Enough Data to Assess
- Asthma A1
- Cancer Prevention B1, B2
- Coronary heart disease E1
- HIV Infection in children and pregnant women G1, G2
- Sepsis—unlikely to have benefitJ1-J3
Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.
Editorial process and description of evidence categories can be found at EBSCO NAT Editorial Process.
Safety Notes
It is likely safe to take selenium in small doses . Doses higher than 400 micrograms daily may not be safe. Women who are pregnant or breastfeeding should especially avoid excessive doses of selenium.
Interactions
Talk to your doctor about any supplements or therapy you would like to use. Some can interfere with treatment or make conditions worse such as:
- People with diabetes should talk to their doctors before taking selenium. It may worsen symptoms.
References
REFA Asthma
REFA1 Allam MF, Lucane RA. Selenium supplementation for asthma. Cochrane Database Syst Rev. 2004;(2):CD003538.
REFB Cancer Prevention
REFB1 Lee EH, Myung SK, et al. Effects of selenium supplements on cancer prevention: meta-analysis of randomized controlled trials. Nutr Cancer. 2011 Nov;63(8):1185-1195.
REFB2 Vinceti M, Filippini T, et al. Selenium for preventing cancer. Cochrane Database Syst Rev. 2018;1:CD005195.
REFC Cardiovascular Disease
REFC1 Rees K, Hartley L, et al. Selenium supplementation for the primary prevention of cardiovascular disease. Cochrane Database Syst Rev. 2013;(1):CD009671.
REFD Cognitive Function
REFD1 Rutjes AW, Denton DA, et al. Vitamin and mineral supplementation for maintaining cognitive function in cognitively healthy people in mid and late life. Cochrane Database Syst Rev. 2018 Dec 17;12:CD011906.
REFE Coronary Heart Disease
REFE1 Ju W, Li X, et al. Th effect of selenium supplementation on coronary heart disease: A systematic review and meta-analysis of randomized controlled trials. J Trace Elem Med Biol. 2017;44:8-16.
REFF Critical Illness
REFF1 Huang TS, Shyu YC, et al. Effect of parenteral selenium supplementation in critically ill patients: a systematic review and meta-analysis. PLoS One. 2013;8(1):e54431.
REFF2 Landucci F, Mancinelli P, et al. Selenium supplementation in critically ill patients: a systematic review and meta-analysis. J Crit Care. 2014 Feb;29(1):150-156.
REFF3 Allingstrup M, Afshari A. Selenium supplementation for critically ill adults. Cochrane Database Syst Rev. 2015;(7):CD003703.
REFF4 Zhao Y, Yang M, et al. The clinical outcomes of selenium supplementation on critically ill patients: A meta-analysis of randomized controlled trials. Medicine (Baltimore). 2019 May;98(20):e15473.
REFG HIV Infection
REFG1 Siegfried N, Irlam JH, et al. Micronutrient supplementation in pregnant women with HIV infection. Cochrane Database Syst Rev. 2012 Mar 14;(3):CD009755.
REFG2 Irlam JH, Siegfried N, et al. Micronutrient supplementation for children with HIV infection. Cochrane Database Syst Rev. 2013 Oct 11;(10):CD010666.
REFG3 Visser ME, Durao S, et al. Micronutrient supplementation in adults with HIV infection. Cochrane Database Syst Rev. 2017 May 18;5:CD003650.
REFH Lipid Profile
REFH1 Hasani M, Djalalinia S, et al. Effect of Selenium Supplementation on Lipid Profile: A Systematic Review and Meta-Analysis. Horm Metab Res. 2018 Oct;50(10):715-727.
REFI Metabolic Syndrome
REFI1 Tabrizi R, Akbari M, et al. The Effects of Selenium Supplementation on Glucose Metabolism and Lipid Profiles Among Patients with Metabolic Diseases: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Horn Metab Res. 2017;49(11):826-830.
REFJ Sepsis
REFJ1 Alhazzani W, Jacobi J, et al. The effect of selenium therapy on mortality in patients with sepsis syndrome: a systematic review and meta-analysis of randomized controlled trials. Crit Care Med. 2013;41(6):1555-1564.
REFJ2 Kong Z, Wang F, et al. Selenium supplementation for sepsis: a meta-analysis of randomized controlled trials. Am J Emerg Med. 2013;31(8):1170-1175.
REFJ3 Li S, Tang T, et al. A meta-analysis of randomized controlled trials: Efficacy of selenium treatment for sepsis. Medicine (Baltimore). 2019 Mar;98(9):e14733.