Selenium is a mineral found in soil, water, and some foods. We need trace amounts for normal health, and selenium is an essential element in several metabolic pathways. It also has antioxidant properties that help prevent cellular damage from free radicals. One of its most valuable roles is as a cofactor of glutathione peroxidase, an important antioxidant enzyme. Selenium also helps support a strong immune system, regulates thyroid function, and may help reduce the risk of prostate and secondary cancers. It also plays a role in the prevention of cataracts and heart disease.
Plasma and serum contains 75 percent of the selenium measured in whole blood and reflects recent dietary intake.
Erythrocytes are heavily loaded with protective selenium enzymes. Measuring erythrocyte selenium content is the best way to check selenium status. Functioning synergistically with vitamin E, selenium protects against cellular damage from oxygen radicals. Thyroid hormone activation relies on the presence of sufficient selenium. Optimal serum selenium concentrations are also associated with lower depressive symptoms and negative mood among young adults.
Food sources:
Garlic, onions, broccoli, Brazil nuts, brewer’s yeast.
References:
- https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/414000
- https://www.ncbi.nlm.nih.gov/pubmed/18299496
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873298/
- https://www.sciencedirect.com/science/article/pii/S0946672X17305680
- http://cebp.aacrjournals.org/content/15/2/315
- https://watermark.silverchair.com/59.pdf
Selenium (Genova)
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