Biotin is the headliner of nearly every “hair, skin & nails” gummy on the shelf, which tells you more about marketing than medicine. Here’s the honest answer: it works if you’re deficient, and does almost nothing if you’re not — and most people aren’t.
What Biotin Does
Biotin (vitamin B7) helps produce keratin, the protein your hair is made of. If you’re genuinely low, correcting the deficiency can visibly improve hair, skin and nails.
The Catch: Deficiency Is Rare
Biotin is in eggs, nuts, seeds, salmon, sweet potatoes, and your gut bacteria make some too. For the average person eating a normal diet, extra biotin just gets filtered out.
Dosage — and a Real Warning
Labels push megadoses (5,000–10,000 mcg) far beyond the ~30 mcg daily baseline. High-dose biotin can seriously skew lab tests — thyroid panels, hormone tests, even the heart-attack blood test. Tell your doctor and stop it a few days before bloodwork.
What to Do Instead
If your hair is genuinely shedding, the deficiencies that actually matter are usually iron (ferritin), vitamin D, and sometimes zinc — not biotin. A simple blood test tells you which to correct.
The Bottom Line
Biotin helps the small number of people who are deficient and does essentially nothing for everyone else. Get tested, correct what’s actually low.
Informational only, not medical advice.