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Learn · Vitamins, Minerals & Exposure

Selenium, RBC

Measured in mcg/L — ICP-MS

The mineral your body uses to convert T4 into active T3, and to run its main antioxidant enzymes. The gap between enough and too much is narrower than for almost any other nutrient.

What the numbers mean

These are the ranges BioForge works to. They are not the same as a lab's reference range, which is built from the general population rather than from people who feel well.

Low
<120 · Impairs T4 to T3
Optimal
150–250 · Lab interval 120–300
High
>300 · Stop supplementing, recheck

What moves Selenium, RBC

Two Brazil nuts a day will move it. Rises with supplements and in high-selenium soil regions; falls with malabsorption and very low protein intake. Selenium excess shows up as hair loss, brittle nails, and a garlic odor on the breath — one of the few supplement overdoses that is genuinely easy to reach.

Related markers in Vitamins, Minerals & Exposure

This page is educational and is not medical advice. Ranges are general and do not account for your history, medications or symptoms — a single number never decides a protocol. Your results are interpreted by a licensed clinician alongside everything else about you. Back to the Learning Center

Results Start Here

Want to know where your numbers actually sit?

Every BioForge protocol starts from your own bloodwork. The first 15-to-30-minute call is free.

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