Urolithin A
At a glance
- Best for
- middle-aged and older adults targeting muscle mitochondrial health and endurance
- Typical dose
- 500–1000 mg/day with food
- Time to effect
- Weeks to a few months
- Main caution
- Limited long-term safety data; avoid in pregnancy and breastfeeding
What is it
Urolithin A is a metabolite produced by gut bacteria from ellagitannins and ellagic acid, polyphenols found in pomegranates, walnuts, and certain berries. The body cannot make urolithin A directly from these foods; instead the right gut microbes convert the dietary precursors into it. Because only a portion of people harbour the bacteria needed to produce meaningful amounts, urolithin A is increasingly sold as a supplement so that the active compound can be delivered directly regardless of gut flora.
Is it worth it for you?
Worth considering if…
- You are middle-aged or older and want to support muscle mitochondrial function
- You will take it consistently for one to several months
- You do not reliably produce urolithin A from food (most people)
Probably skip if…
- You expect large gains in raw strength or athletic performance
- You want an acute pre-workout effect
- You are pregnant or breastfeeding
Evidence at a glance
| Goal | Evidence | Effect | Best fit | Time |
|---|---|---|---|---|
| muscle endurance and mitochondrial health | Limited Evidence | Modest improvements in muscle endurance and mitochondrial markers | middle-aged and older adults with declining muscle function | Weeks to months |
| cellular and mitochondrial ageing | Limited Evidence | Improved mitophagy and mitochondrial biomarkers | adults interested in mitochondrial-ageing pathways | Weeks |
| exercise capacity in healthy adults | Limited Evidence | Inconsistent; small if any | active adults hoping to extend exercise capacity | Weeks to months |
Evidence for 3 uses
AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.
muscle endurance and mitochondrial health
Supplement benefitUrolithin A stimulates mitophagy, the clearance of damaged mitochondria, and randomized trials in middle-aged and older adults report improved muscle mitochondrial gene expression, mitochondrial-health markers, and some measures of muscle endurance. Effects on raw strength and peak performance are more modest and not always significant. Because only a minority make it efficiently from food, direct supplementation delivers a consistent dose.
Bottom line: Urolithin A modestly improves muscle endurance and mitochondrial markers in older adults, with smaller effects on strength.
cellular and mitochondrial ageing
Mechanism onlyIn worms and aged mice, urolithin A extends lifespan and improves muscle function, and human studies show changes in mitochondrial gene expression and biomarkers. Evidence for slowing human ageing rests on preclinical models and biomarker changes, not clinical ageing outcomes. This claim is mechanistic and should not be read as proven anti-ageing benefit.
Bottom line: Anti-ageing claims rest on animal and biomarker data, not human clinical outcomes.
exercise capacity in healthy adults
Supplement benefitTrials examining whole-body exercise performance and aerobic capacity in healthy adults have shown inconsistent results, with mitochondrial and endurance markers improving more reliably than overall performance. Confidence for a meaningful exercise-capacity benefit is low. It is better framed as muscle-quality support than a performance enhancer.
Bottom line: Urolithin A does not reliably boost overall exercise capacity in healthy adults.
Evidence is mixed
Mitochondrial and endurance markers improve, but effects on whole-body exercise performance are inconsistent across trials.
How it works
How to take it
- Typical dose
- 500–1000 mg/day (250 mg also studied)
- Timing
- Once daily with a meal
- With food
- Take with food, ideally containing some fat
- How long to try
- One to four months of consistent use
What to track
- muscle endurance and fatigue
- exercise capacity
- consistency over weeks
2 commercial forms
Synthetic urolithin A (defined ingredient)
Delivers a consistent dose directly, bypassing the need for gut bacteria to produce it from dietary precursors.A standardised, highly pure form produced by synthesis rather than extraction; this is the form used in most clinical trials.
Pomegranate extract (ellagitannin source)
Conversion to urolithin A depends on the individual's gut bacteria; only a minority of people produce substantial amounts.Provides the dietary precursors (ellagic acid and ellagitannins) rather than urolithin A itself.
Safety
Common side effects
mild, transient digestive complaints (no more than placebo in trials)
Who should avoid it
- pregnant and breastfeeding women
- people on multiple medications or scheduled for surgery without clinician input
Pregnancy & breastfeeding
Insufficient safety data; avoid in pregnancy and breastfeeding.
Interactions
Food sources
| Food | Amount | %DV |
|---|---|---|
| Pomegranate (juice and arils) | provides ellagitannin precursors, not urolithin A directly | — |
| Walnuts | rich in ellagitannins (precursors) | — |
| Raspberries | contain ellagic acid (precursor) | — |
| Strawberries | contain ellagic acid (precursor) | — |
Choosing a product
Look for
- defined urolithin A ingredient (e.g. GRAS-notified)
- stated dose 250–1000 mg
- third-party tested
Be skeptical of
- reverses ageing
- guaranteed strength or performance gains
- longevity cure claims
Frequently asked questions
Can I just eat pomegranates instead of supplementing?⌄
Sometimes. Pomegranates and walnuts provide the precursors, but your gut bacteria have to convert them into urolithin A. Studies suggest only around a third to a half of people produce meaningful amounts, which is why a direct supplement gives a more reliable dose.
What is mitophagy and why does it matter?⌄
Mitophagy is the cell's process for recycling damaged mitochondria, the structures that produce energy. It declines with age. Urolithin A's main proposed benefit is stimulating mitophagy to keep muscle and other tissues energetically healthy.
Will urolithin A make me stronger?⌄
The clearest human evidence is for improved muscle endurance and mitochondrial markers, not raw strength. Effects on maximal strength and performance have been modest and inconsistent across trials.
What dose is used in studies?⌄
Most clinical trials used 500 mg or 1000 mg per day with food for one to four months. Lower doses have also been tested.
Is urolithin A safe?⌄
In trials lasting up to a few months at doses up to 1000 mg per day it was well tolerated, with side effects similar to placebo. Long-term safety over years is not yet established.
References by claim
Track Urolithin A with Pilora
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Coming to App StoreDisclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.