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Vitamins & Minerals

SeleniumEvidence & Dosage

Thyroid, antioxidant, selenomethionine, and safety upper limits.

Studies last updated

Evidence at a glance

Total studies
1,000
With abstract
48
Meta / Systematic / RCT
104
Highly cited
50
Publication years
1989–2026

Selenium in the context of Vitamins & Minerals

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Top studies on Selenium

Ranked by influential-citation count and publication year.

  1. Selenium Supplementation in Patients with Hashimoto Thyroiditis: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.

    Thyroid2024n=35meta177 influential citations

    Background: Hashimoto thyroiditis (HT) is the most common cause of hypothyroidism in iodine-sufficient areas. Selenium is an essential trace element required for thyroid hormone synthesis and exerts antioxidant effects. Therefore, it may…

    Finding: No significant changes were observed in fT4, T4, fT3, T3, TGAb, thyroid volume, IL-2, and IL-10.

  2. Protective role of antioxidant supplementation for depression and anxiety: A meta-analysis of randomized clinical trials.

    J Affect Disord2023n=52Meta-Analysis99 influential citations

    <h4>Background</h4>New research supports an integrated approach to treating depression, and lifestyle modifications should be a regular component of both preventative and treatment programs. Therefore, in order to investigate the…

    Finding: The subgroup analyses by scale type and country remained significant for the positive effects on depressive and anxiety states.

  3. Protective Effects of Micronutrient Supplements, Phytochemicals and Phytochemical-Rich Beverages and Foods Against DNA Damage in Humans: A Systematic Review of Randomized Controlled Trials and Prospective Studies.

    Adv Nutr2023n=124Systematic Review63 influential citations

    Accumulation of deoxyribonucleic acid (DNA) damage diminishes cellular health, increases risk of developmental and degenerative diseases, and accelerates aging. Optimizing nutrient intake can minimize accrual of DNA damage. The objectives…

  4. Minerals and Sarcopenia in Older Adults: An Updated Systematic Review.

    J Am Med Dir Assoc2023n=45Systematic Review63 influential citations

    <h4>Objective</h4>This systematic review aims to reevaluate the role of minerals on muscle mass, muscle strength, physical performance, and the prevalence of sarcopenia in community-dwelling and institutionalized older…

  5. The Role of Selected Trace Elements in Oxidoreductive Homeostasis in Patients with Thyroid Diseases.

    Int J Mol Sci2023Systematic Review63 influential citations

    Impaired levels of selenium (Se), zinc (Zn), copper (Cu), iron (Fe), manganese (Mn) and iodine (I) in the organism may adversely affect the thyroid endocrine system. These trace elements play a role in the fight against oxidative stress as…

  6. Association of Selenium Levels with Neurodegenerative Disease: A Systemic Review and Meta-Analysis.

    Nutrients2023n=5,334Meta-Analysis57 influential citations

    Background: Neurodegenerative diseases (NDs) have posed significant challenges to public health, and it is crucial to understand their mechanisms in order to develop effective therapeutic strategies. Recent studies have highlighted the…

    Finding: The authors concluded that AD patients are strongly associated with lower selenium concentrations compared with healthy people.

  7. Effects of Selenium Administration on Blood Lipids: A Systematic Review and Dose-Response Meta-Analysis of Experimental Human Studies.

    Nutr Rev2026n=27Meta-Analysis50 influential citations

    <h4>Context</h4>Overexposure to the essential trace element selenium has been associated with adverse metabolic and cardiovascular outcomes, hypertension, and diabetes. However, dose-response meta-analyses analyzing the effects of selenium…

    Finding: Inorganic selenium supplementation showed stronger associations than organic selenium.

  8. The Influence of Nutritional Intervention in the Treatment of Hashimoto's Thyroiditis-A Systematic Review.

    Nutrients2023n=2Systematic Review49 influential citations

    Diet can be a complementary treatment for Hashimoto’s disease by affecting thyroid function and anti-inflammatory properties. It is still unclear which dietary strategy would be the most beneficial. The aim of this systematic review is to…

  9. Selenium supplementation decreases CRP and IL-6 and increases TNF-alpha: A systematic review and meta-analysis of randomized controlled trials.

    J Trace Elem Med Biol2023n=24Meta-Analysis41 influential citations

    Inflammation is an initiating cause of infectious and non-infectious diseases. Studies have shown that selenium (Se) has anti-inflammatory effects. However, its' effects on serum c-reactive protein (CRP), interleukin-6 (IL-6), and tumor…

    Finding: Intravenous selenium supplementation significantly reduced CRP concentration in the pooled analysis.

  10. Dietary Supplements Potentially Target Plasma Glutathione Levels to Improve Cardiometabolic Health in Patients with Diabetes Mellitus: A Systematic Review of Randomized Clinical Trials.

    Nutrients2023Systematic Review38 influential citations

    Cardiovascular diseases (CVDs) continue to be the leading cause of death in people with diabetes mellitus. Severely suppressed intracellular antioxidant defenses, including low plasma glutathione (GSH) levels, are consistently linked with…

Frequently asked

What does the evidence say about Selenium?
No significant changes were observed in fT4, T4, fT3, T3, TGAb, thyroid volume, IL-2, and IL-10.
What dosage was studied?
• Selenium supplementation (80 to 400 μg/day) • Antioxidant supplementation (including magnesium, zinc, selenium, CoQ10, tea and coffee, and crocin) (Not reported) • Micronutrient supplements and phytochemicals, including vitamin A, beta-carotene, vitamins C, E, B1, B12, folate, selenium, zinc, curcumin with piperine, lycopene, and proanthocyanidins (Not reported)
Which population does the evidence apply to?
Most studies investigated: unknown; patient.
Are there safety considerations for Selenium?
• No significant difference in adverse events versus control (OR 0.89, 95% CI 0.46 to 1.75). • Five cohorts reported 2-19 adverse events, including GI symptoms, dizziness, and hair loss. • Miscarriages were among reported adverse events in pregnant participants. • Excess selenium intake at 300-400 μg/day can cause acute toxicity.

Related articles

Blog

Selenium for the Thyroid: What Hashimoto Studies Really Show

Selenium can lower TPO antibodies in Hashimoto, especially at 200 µg/day in studies. What is actually proven, which forms exist, and where the risks lie.

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