Does collagen help hair and nails?

What does the research show for nails?

The best-known trial is Hexsel and colleagues (2017). Twenty-five women took 2.5 g of bioactive collagen peptides a day for 24 weeks. Nail growth rate rose about 12% and the frequency of broken nails fell by about 42%. That sounds impressive, but the study was open-label with no placebo group, it was small, and its authors included researchers from a collagen research institute that works with the peptide's manufacturer (the funding source was not stated in the report we read). The authors themselves called for larger placebo-controlled trials. Treat it as a reason to run better studies, not as proof.

And for hair?

We found no robust placebo-controlled trial of oral collagen for hair growth in our research files, so any claim that collagen "grows hair" goes beyond the evidence. Hair and nails are made of keratin, not collagen. The plausible route is indirect: adequate protein, iron and zinc support normal hair and nail growth, and collagen contributes amino acids. But collagen lacks tryptophan, so it is a poor protein source (is collagen a complete protein).

Collagen vs biotin: what is the difference?

If you take biotin, tell your doctor before blood tests. We look at it in more detail in does biotin help hair growth.

What actually helps hair and nail health?

• Enough protein: most adults do well on a protein source at every meal.
• Iron status: low ferritin is a common, treatable contributor to hair shedding, especially in women with heavy periods. Test before supplementing (do women need iron supplements).
• Medical causes: thyroid problems, hormonal changes, medication and stress can all change hair and nails.
• Gentle handling: heat, bleach and constant water exposure damage nails and hair shafts regardless of what you swallow.

Is it worth trying?

If you want to experiment, 5 to 10 g a day for at least 12 weeks is reasonable and low-risk for most healthy adults. As of October 2026, a 10 g dose of ATP Fitness Hydrolysed Collagen costs R10.44 using the 910 g tub (R950, ATP shop); The Harvest Table 800 g refill is R11.36 (R909, Faithful to Nature). ATP's trade-offs are that it is unflavoured and no third-party certificate is published. Expect no change in some people, and stop if you do not notice anything by about three months rather than doubling the dose.

When to see a doctor

Sudden or patchy hair loss, nails that change colour or shape, or ridges and pitting can point to an underlying condition. See a GP or dermatologist. Pregnant or breastfeeding women should check with their doctor before starting any collagen product.

Under-18s should see a doctor about hair or nail changes rather than self-treating, and anyone with kidney disease or on regular medication should check before starting collagen or biotin.

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