Urolithin A

What it is

Urolithin A is produced by gut bacteria from ellagitannins, compounds found in pomegranates, walnuts and some berries. Not everyone has the right bacteria to make much of it.

Supplements deliver urolithin A directly. The best-known product is Mitopure, and much of the research is linked to the company that makes it.

It is positioned as supporting mitophagy, the clearing and renewal of old mitochondria.

How it works

In lab and animal studies, urolithin A seems to trigger mitophagy, the process of recycling damaged mitochondria. The idea is that this may support muscle and cellular energy, particularly with age.

What the evidence says

• Limited Muscle endurance in older adults
  A few randomised trials report improved endurance measures, though many are small and industry-linked.
• Limited Markers of mitochondrial health
  Blood and muscle biomarker changes have been reported, with unclear real-life effect.
• Weak Reducing inflammation markers
  Early findings in small trials; not firmly established.
• Weak Slowing ageing
  No evidence it affects lifespan in people.

Evidence ratings are our plain-English summary of how much good human research exists, not a promise of results. How we rate evidence.

Dosage and timing

• Studied doses are about 500-1,000 mg daily.
• Trials run for weeks to a few months.
• Taking it with food is fine; timing seems not to matter much.
• No official recommended intake; check current guidance and the label.

Forms and what to look for

• Purified urolithin A in capsule form is the main supplement type.
• Pomegranate extract products do not reliably produce urolithin A, because it depends on your gut bacteria.
• Look for products stating mg of urolithin A specifically.
• Branded versions have more trial data than generic ones.

What to expect, and when

• Studies assessing muscle endurance ran 2-4 months.
• Many people will not notice a change.
• Biomarker shifts may appear sooner than anything you can feel.

Side effects

• Generally well tolerated in short trials.
• Mild digestive discomfort.
• Headache in some people.
• Long-term effects are largely unknown.

Interactions

• No well-established drug interactions, but data are limited.
• Pomegranate-derived products: pomegranate juice can interact with some medicines (for example, certain statins and warfarin); urolithin A itself is less studied.
• Other mitochondrial supplements: combining them has no proven benefit.
• Check with a pharmacist if you take regular medication.

Who should avoid it

• Pregnant or breastfeeding women, due to limited data.
• Children and teenagers.
• People with serious health conditions without a clinician's input.
• Anyone with a known allergy to nuts or pomegranate, depending on product source.

Risks and safety

• Long-term safety beyond a year or so is unstudied.
• Much of the research comes from the company selling the product.
• Regulatory status of novel ingredients in the UK and EU may change; check current guidance.
• It is expensive relative to the evidence.

Buying well: quality and testing

• Choose products with third-party testing and a clear urolithin A amount.
• Be cautious of pomegranate extracts claiming the same effect.
• Look for published trials on the specific product.
• Compare cost per effective dose.

Bottom line

Urolithin A is one of the more interesting newer mitochondrial supplements, with a plausible mechanism and some positive small trials. But the evidence is early, often company-linked, and the cost is high. It suits curious, informed adults with realistic expectations; it is no replacement for exercise and good nutrition.