Encyclopedia · supplement
Urolithin A
A gut-bacteria product of pomegranate and walnut compounds, sold as a mitochondria longevity supplement, protected human hair-papilla cells from oxidative damage in a brand-new 2026 company-linked paper, with no controlled human hair trial.
What it is
Urolithin A is made by gut microbes from ellagitannins in pomegranate, walnuts and berries. Not everyone's gut makes it, which is why it is sold as a supplement. It has no hair indication anywhere.
How it works
It activates mitophagy, the clean-up of damaged mitochondria. In cultured human dermal papilla cells (the follicle's signalling hub) stressed with hydrogen peroxide, it improved mitochondrial function, reduced cell death and raised Wnt and beta-catenin, the signal that keeps follicles in growth. Kwon 2026
What the studies show
- The 2026 paper reports better mitochondrial function, less apoptosis and higher Wnt/beta-catenin in cells, and that topical urolithin A raised hair root volume and cut shedding. The authors are company-affiliated, and we read only the abstract, which does not state the design or size of the clinical part. Kwon 2026
- No registered hair trial of urolithin A was found (checked 2026-10-10).
How it's used in studies
Various concentrations in cell culture and topical application in the clinical part; exact values are not in the abstract.
Side effects and safety
No hair-specific safety data.
Bottom line
A promising mechanism from one very new company-linked paper and no independently validated human result. It is not a substitute for minoxidil or finasteride.
Fun facts
- A molecule your gut bacteria make from pomegranate may talk to hair-papilla cells through the same Wnt switch that drugs target (cell data only). Kwon 2026
Studies 1
Kwon I et al. Urolithin A improves mitochondrial dysfunction induced by oxidative stress in human dermal papilla cells. BMB Rep. 2026
Result: Better mitochondrial function, less apoptosis, Wnt/beta-catenin up; topical use reportedly raised hair root volume and cut shedding; company-affiliated (abstract only).
Read the study ↗Related
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