Condition
Nail Health
Nails are hard plates of keratin that grow about 3 to 4 millimeters a month, and brittleness, splitting or slow growth can reflect aging, harsh chemicals or a nutritional gap. Biotin, the best-studied option for brittle nails, and collagen peptides have moderate evidence, and collagen studies found improved nail growth and strength. Even so, the evidence is moderate at best, and a small gelatin study offered only limited support.
- Updated
- How we grade
- Nail Health protocol
- Supplements studied
- 1
- Graded outcomes
- 1
- Trials
- 1
- People studied
- 22
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Nail Strength Some evidence for improved nail growth and reduced brittleness | Improves (the measure goes up) | Small effect | 80 people |
Key findings
- Nail StrengthImproves (the measure goes up)
The Nail Health Support protocol
2 primary supplements · 6 supporting supplements
- Biotin2,500–5,000 mcg (2.5–5 mg) daily
- Collagen Peptides5–10 g daily
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