Daily Selenium Intake Calculator
NIH-recommended daily selenium intake by age and pregnancy or breastfeeding status.
A general population guideline (NIH RDA), not medical advice — selenium toxicity is possible at high supplemental doses, so more isn't automatically better once dietary needs are met.
Recommended daily selenium
55 mcg
NIH RDA guideline
For informational and educational purposes only — not medical advice, and not a substitute for consulting a qualified professional about your specific situation. TrueMeasureKit is not liable for decisions made based on these results. See our Terms of Service.
Why selenium is one of the easiest nutrients to over-supplement
Selenium supports thyroid function and acts as an antioxidant, but the gap between the RDA (55mcg for most adults) and the tolerable upper intake level (400mcg/day) is narrower than for many other nutrients — partly because a single Brazil nut can contain anywhere from 50 to over 100mcg depending on the soil it grew in, making it easy to get a meaningful dose from food alone without any supplement at all.
Frequently asked questions
Why does the recommended intake change so little across most adult groups?
Selenium requirements are relatively stable across most adult life stages compared to some other nutrients, with the notable exception of pregnancy and breastfeeding, which the NIH RDA accounts for with a modestly higher target.