Biotin

Also known as: Vitamin B7, Vitamin H, Coenzyme R, d-Biotin

Evidence under review. — Not yet rated

B vitamin essential for metabolism. Little clinical proof it grows hair or nails in healthy people.

What it does

Biotin is a water-soluble B vitamin (B7) that your body uses to help convert food into energy and support the function of enzymes involved in fat, carbohydrate, and protein metabolism. It is found...
Evidence quality

Evidence base hasn't been formally rated yet. See research below.
Clinical dose

No established dose from provided studies
Found in

Key Nutrients Electrolyte Recovery Plus Powder, Vital Hair, Skin and Nails (30's), Augustinus Bader The Hair Revitalizing Complex and 17 more

What the Science Says

Biotin is a water-soluble B vitamin (B7) that your body uses to help convert food into energy and support the function of enzymes involved in fat, carbohydrate, and protein metabolism. It is found naturally in many foods and is also produced by gut bacteria. The provided research does not include clinical trials demonstrating that biotin supplementation improves hair growth, nail strength, or skin health in people who are not deficient — one small crossover trial compared biotin to minoxidil for hair growth in men but provided no extractable results.

What It Doesn't Do

No proof it grows hair or thickens nails in healthy people — that claim is marketing, not science. Won't boost energy levels beyond correcting a true deficiency. Not a treatment for hair loss. The research provided does not support any cognitive, weight loss, or skin-clearing benefits.

Evidence-Based Benefits

Biotin is a B-vitamin used as a cofactor in metabolic processes; one crossover RCT (PMID: 38688776) compared 5 mg oral biotin to 5% topical minoxidil for male hair growth, though no abstract was available to confirm outcomes. High-dose biotin supplementation has been documented to cause proximal renal tubular acidosis in at least one case report with rechallenge confirmation (PMID: 41835731). Biotin is also used as a reagent in many laboratory immunoassays, where exogenous supplementation can cause significant false-positive or false-negative interference across a wide range of clinical tests (PMID: 41876205).

Weak Evidence

Effective at: No established dose from provided studies for cosmetic/hair use; 2,500 µg/day associated with adverse effects (PMID: 41835731)

Source: auto-research

Absorption & Bioavailability

Unknown from provided studies — no pharmacokinetic data for standard oral biotin supplementation was included in the provided papers.

Red Flags to Watch For

High-dose biotin (2,500 µg/day or more) has been linked in a case report to a rare but serious condition called proximal renal tubular acidosis, causing dangerous electrolyte imbalances — symptoms resolved only after stopping the supplement
Biotin supplements at high doses can interfere with dozens of common lab tests (thyroid, troponin, hormone panels), causing falsely high or falsely low results — this is a documented safety concern confirmed in laboratory studies
Most people are not biotin-deficient, so supplementing provides no proven benefit for hair, nails, or skin
Supplement labels often contain doses hundreds of times the daily requirement with no clinical justification for those amounts

Supplement

Not A Product

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Frequently Asked Questions

What does Biotin do?

B vitamin essential for metabolism. Little clinical proof it grows hair or nails in healthy people.

What is the effective dose of Biotin?

No established dose from provided studies

Is Biotin safe?

High-dose biotin (2,500 µg/day or more) has been linked in a case report to a rare but serious condition called proximal renal tubular acidosis, causing dangerous electrolyte imbalances — symptoms resolved only after stopping the supplement

What doesn't Biotin do?

No proof it grows hair or thickens nails in healthy people — that claim is marketing, not science.

Research Sources

PubMed
NIH DSLD

This information is for educational purposes only and is not medical advice. Always consult a healthcare professional before starting any supplement regimen. Last updated: 2026-04-06