Vitamin B7 (Biotin)
Body function
Metabolism of fats, carbohydrates, and protein; supports hair, skin, and nails
Daily requirement
~30 mcg/day for adults
Deficiency signs
Rare; thinning hair, brittle nails, skin rash, fatigue
Excess risks
Low toxicity, but high-dose biotin can interfere with some lab tests (such as thyroid and troponin)
At-risk groups
Pregnant women, heavy alcohol users, people with rare genetic disorders
Supplement forms
Biotin (D-biotin); often in hair, skin, and nail and B-complex products
Food sources
- Eggs (whole, boiled) — ~20 mcg per 2 eggs
Related symptoms
Educational information only — not medical advice. This content does not diagnose, treat, or replace consultation with a qualified healthcare professional. Always seek professional medical advice for symptoms, supplement use, or health concerns.