Ranked by evidence
Best supplements for skin, hair and nails
Skin, hair and nails is the category where supplement marketing runs furthest ahead of the research. This list is ordered by how strong the evidence actually is for this goal, using the site's own grades, not by how popular the product is. The short version: collagen peptides have real but modest data for skin, and almost nothing has convincing data for hair or nails.
Evidence last reviewed: August 2026
Top picks
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Collagen Peptides | Moderate evidence | skin elasticity and hydration | Hydrolyzed collagen peptides have moderate-grade evidence for improved skin elasticity and hydration. The joint-comfort claim is much weaker. | View |
| Marine Collagen | Moderate evidence | collagen without bovine sources | Fish-derived type I peptides do about as well as bovine ones for skin hydration and elasticity; the "better absorbed" marketing is not supported. | View |
Solid options
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Niacinamide | Moderate evidence | skin cancer prevention in high-risk adults | 500 mg twice daily cut new non-melanoma skin cancers by about 23% in high-risk immunocompetent adults. Not a cosmetic supplement. | View |
Situational
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Oregon Grape | Limited evidence | mild plaque psoriasis, as a cream | As a cream it beats placebo in mild-to-moderate plaque psoriasis, though it loses to prescription topicals. Oral capsules have no such evidence. | |
| Gelatin | Moderate evidence | a cheap collagen source | Same amino acids as collagen peptides for less money; its moderate-grade evidence is for collagen synthesis with vitamin C, not skin appearance. | View |
| Manuka Honey | Limited evidence | wound care, applied to the skin | Medical-grade honey has moderate evidence as a topical wound dressing. Eating it does nothing measurable for skin, immunity or gut. |
Popular for this goal — but the evidence says skip
- Biotin (Vitamin B7) Limited evidence
The default hair-and-nail pill, with close to no evidence in people who are not deficient, and it distorts common blood tests, including troponin.
- Hair-Skin-Nails Formulas Limited evidence
Built around megadose biotin, which does nothing for hair in people who are not deficient and reliably corrupts laboratory results.
- Hyaluronic Acid Limited evidence
The oral skin-hydration trials are small, concentrated in one country and usually funded by ingredient makers; it is also not the same as the injections.
- Bamboo Silica Limited evidence
Sold as silica for hair and nails, but the silica in bamboo is largely insoluble and poorly absorbed, and the trials behind the claim are weak.
- Evening Primrose Oil Limited evidence
A Cochrane review of 27 trials found no benefit for eczema, one of the clearest negative results in the whole skin category.
- He Shou Wu (Fo-Ti) Limited evidence
Sold for regrowing and re-darkening hair on the strength of a legend, and it is one of the best-documented herbal causes of liver injury.
Our verdict
If you try one thing, make it collagen peptides, bovine or marine, with realistic expectations: modest gains in skin hydration and elasticity, not a transformation. For hair and nails specifically, nothing in the catalog earns better than a limited grade.