Urolithin A: What It Is, Benefits, and Where to Buy

Urolithin A is one of the most compelling compounds to emerge from longevity research in the past decade. It is not a plant extract or a vitamin — it is a postbiotic metabolite that your gut microbiome produces (or fails to produce) from the ellagitannins found in pomegranate, walnuts, and certain berries. The problem is that only about 40% of the population has the gut flora needed to produce it.

What is urolithin A

Urolithin A (UA) is a metabolite produced by gut bacteria of the Gordonibacter and Ellagibacter genera from ellagitannins — polyphenols abundant in pomegranate, walnuts, raspberries, and blackberries. It does not exist as such in any food: it is the result of a microbial transformation in the colon.

What makes urolithin A special is its mechanism of action: it is the first natural compound identified that selectively activates mitophagy — the process by which cells eliminate damaged or dysfunctional mitochondria and replace them with new ones.

The bioconversion problem

Not everyone produces urolithin A. Studies from Amazentis (the Swiss company behind Mitopure) and EPFL show that the ability to convert ellagitannins into urolithin A depends entirely on the composition of the microbiome:

• ~40% of the population produces UA in meaningful quantities
• ~30% produces minimal or intermediate amounts
• ~30% does not produce UA at all

This explains why eating pomegranate does not guarantee the benefits of urolithin A — and why direct supplementation makes sense.

Mechanism of action: mitophagy

Mitochondria are the energy powerhouses of the cell. With age, they accumulate damage and lose efficiency — a process directly linked to muscle aging, fatigue, and neurodegeneration.

Mitophagy is the quality control system: it identifies damaged mitochondria, tags them for destruction, and facilitates the generation of new ones. Urolithin A activates this process through:

1. PINK1/Parkin activation — the primary mitophagy signaling pathway
2. BNIP3L induction — a mitophagy receptor on the mitochondrial membrane
3. Increased mitochondrial biogenesis — it does not just eliminate damaged mitochondria but also stimulates the production of new ones
4. Reduced oxidative stress — by removing mitochondria that produce excess ROS

The net result: a younger, more efficient mitochondrial pool in muscle, cardiac, and neuronal cells.

Clinical evidence

EPFL/Amazentis 2019 study (Nature Metabolism)

The first clinical trial in humans (Andreux et al., 2019) administered 250mg, 500mg, and 1000mg of urolithin A to sedentary adults over 4 weeks. Results:

• Significant improvement in mitochondrial function biomarkers
• Reduction in plasma acylcarnitines (a marker of mitochondrial dysfunction)
• Improved mitophagy gene expression in muscle biopsies
• No relevant adverse effects at any dose

ATLAS 2022 study (JAMA Network Open)

The most important study to date: a randomized, double-blind, placebo-controlled trial. 66 older adults (65–90 years) received 1000mg of Mitopure for 4 months.

• +12% in knee extension strength vs placebo
• Improved muscular endurance (distance covered in 6 minutes)
• Reduction in inflammation biomarkers (CRP, IL-6)
• Excellent safety profile

Ongoing studies

Amazentis has multiple active trials in sarcopenia, cognitive function, and joint health. The FDA granted GRAS (Generally Recognized as Safe) status to urolithin A in 2018.

Gold standard

Ingredients · Mitophagy

Timeline Mitopure

The patented form of urolithin A with the most clinical evidence. 500mg per capsule, developed by Amazentis in collaboration with EPFL. NSF certified for purity.

★★★★★0.0/ 5

6 months of daily use

Desde

$70

30 capsules · 1 month

Natural sources of precursors

Although direct supplementation is more reliable, foods rich in ellagitannins (precursors) include:

| Food | Ellagitannins (mg/100g) | Conversion to UA | |---|---|---| | Pomegranate (juice) | 150–300 | Variable (40% of people) | | Walnuts | 60–120 | Variable | | Raspberries | 40–80 | Variable | | Strawberries | 20–40 | Low | | Blackberries | 30–60 | Variable |

The problem: even when consuming these foods daily, the amount of urolithin A produced is unpredictable and generally lower than the therapeutic dose of 500–1000mg.

Dosage and protocol

Standard dose: 500–1000mg of urolithin A daily Timing: with breakfast or the main meal (absorption improves with food) Minimum duration: 8–12 weeks for measurable effects on muscle biomarkers

500mg or 1000mg?

• 500mg — maintenance dose, sufficient to activate mitophagy
• 1000mg — the dose used in the ATLAS study with adults over 65, with more pronounced results in muscle strength

Comparison

Safety and side effects

Urolithin A has an excellent safety profile:

• GRAS status granted by the FDA (2018)
• No serious adverse effects reported in clinical trials
• No significant known drug interactions
• Well tolerated in older adults (ATLAS study, 65–90 years)
• Rare side effects: mild gastrointestinal discomfort in the first few days

Who should consider it

Yes: adults over 40 interested in mitochondrial and muscle health, especially those who do not regularly consume foods rich in ellagitannins. People with early-stage sarcopenia or muscle fatigue.

Not yet justified: young, active individuals with a polyphenol-rich diet. The cost-benefit ratio is not justified for those under 35 without specific conditions.

Where to buy