Selenium Toxicity (Selenosis): Symptoms, Hair Loss & Safe Limits

Chronic selenium excess causes selenosis — hair and nail loss, GI upset, and nerve symptoms. Learn the safe upper limits and which supplements are most likely to cause selenium overdose.

Selenium Overdose Risk

Chronic selenium excess can cause hair/nail changes, GI upset, and nerve symptoms (selenosis).

Safe Dosage Upper Limits (5 Regional Standards)

StandardRDAUpper Limit (UL)
US (FDA)55 mcg400 mcg
EU (EFSA)55 mcg400 mcg
AU (TGA)55 mcg400 mcg
CN (CNS)60 mcg400 mcg
JP (MHLW)65 mcg350 mcg

RDA = Recommended Dietary Allowance. UL = Tolerable Upper Intake Level. Exceeding the UL long-term may cause the toxicity symptoms described above.

Frequently Asked Questions

Can selenium supplements cause hair loss?

Yes. Chronic selenium excess (selenosis) is one of the most common causes of supplement-related hair loss. Other signs include brittle nails, GI upset, and a garlic-like breath odor. The UL is 400 mcg/day.

Check if Your Selenium Intake Is Safe

Scan your supplement labels with NutriAudit. Automatically calculate total intake from all sources and detect if you exceed safe limits.

Not medical advice. Always consult a qualified healthcare professional for personal medical decisions.