Urolithin A
urolithin A · UA
A gut-derived metabolite that stimulates mitophagy, studied for muscle and mitochondrial health.
TipoSupplement / dietary
Grado
C
Limitata
- Classe
- Mitophagy
- Uso principale
- Mitochondrial & muscle function
- Forza evidenza
- medium
- Ultima revisione
- 2026-07-01
In sintesi
Unusual among supplements in having actual human RCTs — small ones showing better mitochondrial and muscle-endurance markers. Reasonably evidenced for muscle function; broad longevity claims are still a stretch.
Cosa dice l'evidenza
Urolithin A is produced by gut bacteria from ellagitannins in pomegranate and walnuts, but many people convert poorly, which is the rationale for taking it directly. Several randomized human trials report improved mitochondrial gene expression and muscle endurance or strength markers in middle-aged and older adults — generally on surrogate endpoints rather than hard clinical outcomes. That puts it above most supplements on evidence quality, yet it stays at grade C because the trials are small and the outcomes intermediate. It's a good example of 'better evidenced than average' still not meaning 'proven to extend life'.
Studi chiave
- [1]
Urolithin A, mitophagy and muscle endurance (randomized trials) · RCT
Improved mitochondrial markers and muscle endurance on surrogate endpoints.
PubMed ↗ - [2]
Urolithin A safety and pharmacokinetics in humans · RCT
Well tolerated; establishes dosing feasibility.
PubMed ↗ - [3]
Urolithin A and mitochondrial health (review) · review
Synthesises the mitophagy rationale and early human data.
PubMed ↗
Meccanismo
Induces mitophagy — the recycling of damaged mitochondria — improving mitochondrial quality control, with downstream effects on muscle bioenergetics.
Sicurezza
Well tolerated in human trials at the doses studied; safety has been characterised over months rather than years.
Contesto dosaggio
Human trials commonly use ~500–1000 mg/day of a defined form. Eating pomegranate or walnuts does not reliably produce equivalent urolithin A because gut-microbiome conversion varies widely between people.
Nota dal campo
Urolithin A is a rare case: a supplement that actually ran randomized human trials. We still hold it at C, because 'better muscle-endurance markers in small trials' is not the same as 'lives longer'.