What to watch with Selen and longevity?

Selenium is an essential trace mineral incorporated into selenoproteins (e.g., glutathione peroxidases) that protect against oxidative damage and support thyroid function. Observational studies suggest moderate selenium intake may be associated with reduced risk of certain age-related diseases, but robust clinical evidence for extending lifespan is lacking. Excess selenium (e.g., from supplements) can be toxic and may increase diabetes risk. MyBody-X does not offer a dedicated selenium test; its DNA Longevity panel includes variants like FOXO3 (rs2802292) but no direct selenium-related markers. For assessing selenium status, clinically validated blood or toenail tests are recommended. Overall, the evidence for selenium as a longevity intervention is weak and primarily mechanistic/epidemiological. A balanced diet (Brazil nuts, fish, eggs) usually provides adequate intake. Supplementation is not advised without confirmed deficiency.