Key findings from detailed records
Human trials of urolithin A have reported improvements in selected measures of muscle strength and endurance. The clearest signals concern specific muscle tests, rather than a general improvement in walking ability or a proven extension of human lifespan. Here we distinguish those findings from mitochondrial mechanisms, branded ingredients and patents.
KNOWLEDGE RECORD
- Category
- Metabolism and cellular function
- Last Reviewed
Names and related search termsUrolithin A / Urolithin A / UA / Mitopure / Mitophagy
Study type: human intervention study.
OUTCOME-SPECIFIC EVIDENCE
Scientific Evidence Profile
Editorial pilot · selected evidence; not a systematic review or formal GRADE assessment.
Hamstring strength in sedentary middle-aged adults with overweight
Limited
A 4-month trial in 88 randomized adults found improvement versus placebo at 500 and 1,000 mg/day. This supports a specific strength signal, with further independent confirmation needed.
Basis of this assessment
- Human study quality
- Randomized, blinded, placebo-controlled human trials; the positive muscle outcomes were secondary.
- Scale and replication
- Small trials with different tests and populations; independent confirmation of the same outcome is limited.
- Consistency of findings
- Selected muscle measures improved, while primary functional outcomes did not. The result depends on the test and timepoint.
- Clinical relevance
- A measured muscle benefit is more direct than a blood biomarker, but does not establish less disability or longer life.
- Systematic reviews / meta-analyses
- The 2026 review found strength and endurance measures too heterogeneous to pool. Its pooled walking result was inconclusive.
- Limitations / funding / COI
- The central trials were funded by Amazentis and included company-affiliated authors. Limited follow-up and independent replication constrain confidence; funding alone is not the reason for the level.
Assessment sources
Hand and leg muscle endurance in adults aged 65–90
Limited
A 66-person trial of 1,000 mg/day found a placebo-controlled benefit at 2 months, but not at 4 months. Walking distance and maximal ATP production did not show significant primary-outcome benefits.
Basis of this assessment
- Human study quality
- Randomized, blinded, placebo-controlled human trials; the positive muscle outcomes were secondary.
- Scale and replication
- Small trials with different tests and populations; independent confirmation of the same outcome is limited.
- Consistency of findings
- Selected muscle measures improved, while primary functional outcomes did not. The result depends on the test and timepoint.
- Clinical relevance
- A measured muscle benefit is more direct than a blood biomarker, but does not establish less disability or longer life.
- Systematic reviews / meta-analyses
- The 2026 review found strength and endurance measures too heterogeneous to pool. Its pooled walking result was inconclusive.
- Limitations / funding / COI
- The central trials were funded by Amazentis and included company-affiliated authors. Limited follow-up and independent replication constrain confidence; funding alone is not the reason for the level.
Assessment sources
Profile reviewed:
This profile concerns the stated outcome and population, not the ingredient as a whole. It is not a probability of benefit, a safety rating, a product efficacy rating or an indication of product adoption.
How we assess evidenceIngredient Profile
- What is it?
- Urolithin A is a defined small molecule in the urolithin family. Studying an isolated molecule makes a different comparison from studying a complex food or extract. [1]
Sources for this profile
Compound properties and formulation properties are different. These sources do not establish the efficacy of a finished supplement.
- PubChem — Urolithin A (CID 5488186) Chemical identity reference. Maintained by NCBI, U.S. National Library of Medicine. Database record; not a clinical trial.
Profile sources checked:
Read the evidence in context
- Evidence: what was measured in the stated population or experimental model.
- Inference: an interpretation connecting findings; its applicability depends on the study conditions.
- Hypothesis: a proposed explanation or effect that remains to be tested.
Why It Matters #
Maintaining muscle function supports everyday movement. Urolithin A is being studied because it connects gut microbial metabolism with mitochondrial quality control. It offers a useful way to ask whether a cellular mechanism can translate into a measurable functional benefit.
What Was Studied #
Two randomized placebo-controlled trials provide the detailed muscle records below: 88 sedentary, middle-aged adults with overweight were assigned to 500 or 1,000 mg/day or placebo for 4 months; 66 adults aged 65–90 were assigned to 1,000 mg/day or placebo for 4 months. Both studied Mitopure®, but used different muscle tests.[1] [2]
What Was Found #
The middle-aged trial found improved hamstring strength versus placebo at both doses. The older-adult trial found improved hand and leg muscle endurance versus placebo at 2 months. These were secondary findings: the trials did not show significant between-group improvement in their primary peak-power, walking-distance or maximal ATP-production outcomes.[1] [2]
What the Evidence Means #
The muscle findings are encouraging but endpoint-specific. Small samples, short follow-up and limited independent replication constrain confidence. In the older-adult trial, the endurance advantage was not statistically significant at 4 months. Neither study establishes a longer human lifespan.[1]
Comparing similar populations, formulations, durations and outcomes helps identify where findings agree and where they differ.
What We Can Learn #
Ask which muscle, which test and which timepoint improved. A change in blood markers or mitophagy-related proteins answers a different question from walking farther or remaining independent. Match any conclusion to the studied preparation, population and dose.
What Remains Unknown #
Longer trials should establish whether the observed muscle changes persist, translate into daily function and generalize to other populations and preparations. The studies summarized here do not establish multi-year safety or a comprehensive drug-interaction profile.
From the gut to mitochondrial quality control
Food precursors → gut microbes → urolithin A. Ellagitannins and ellagic acid in foods such as pomegranates, berries and walnuts can be converted by gut bacteria. The ability to produce urolithin A varies between people. Direct UA intake bypasses this conversion step; greater blood exposure does not itself demonstrate a greater health benefit.
Singh et al. · 2021/2022Mitophagy is the selective recycling of mitochondria through the cell’s autophagy machinery. UA stimulated this process in preclinical models. Human studies have found changes in mitochondrial gene expression and mitophagy-related muscle proteins, alongside selected functional outcomes. Those molecular observations support a mechanism; they are not a direct measurement of whole-body mitochondrial renewal.
Ryu et al. · 2016 Singh et al. · 2022How the wider evidence fits together
The 2026 systematic review included 5 randomized trials with 236 participants. Only the 6-minute walk test could be pooled across 2 trials: the estimated difference was +17.03 m, with a 95% confidence interval from −5.33 to 39.40 m. This interval includes no difference. Strength and endurance findings were too heterogeneous to pool, so the review does not establish a reproducible overall muscle benefit.
Systematic review · 2026Safety and use in context
In the 4-month older-adult trial, adverse events did not differ statistically from placebo. The middle-aged trial also reported no significant safety differences in the assessed measures. These findings support short-term tolerability in the studied adults. They do not establish safety for every population or for years of use.
[1] [2]The evidence reviewed here is not sufficient to define drug interactions or safety during pregnancy, breastfeeding or childhood. People taking medicines or receiving treatment should discuss use with their clinician. Trial doses are research conditions, not a personal dosing recommendation.
FDA’s response to GRAS notice 791 stated that it had no questions regarding Amazentis’s conclusion for the specified food uses. This is not FDA approval of efficacy or authorization to treat disease.
FDA · GRN 791Research, Commercialization & Intellectual Property
Amazentis is the Swiss company behind the development programme. Mitopure® is its branded urolithin A ingredient; Timeline is its consumer brand. These names describe a company, an ingredient and a brand—not three different molecules. Amazentis describes Mitopure as more than 98% pure UA. This is a manufacturer specification, not a specification for every UA ingredient.
AmazentisThe two detailed muscle trials used Mitopure. Their results belong to the tested preparation, dose and population. Another product with the same molecule should be assessed for identity, purity, formulation and exposure rather than assumed to have identical clinical evidence.
Research and commercialization milestones
- 2016: Preclinical mitophagy research in worms and rodents. Source ↗
- 2018: FDA response to GRAS notice 791 for specified food uses. Source ↗
- 2019: First human study of tolerability and mitochondrial molecular signatures. Source ↗
- 2020: Announcement of the Timeline consumer launch using Mitopure. Source ↗
- 2022: Randomized muscle-function trials in middle-aged and older adults. Source ↗
Three different types of patent protection
US11634401B2
Process: a specified route for process-scale synthesis of UA.
United States · applicant / assignee: Amazentis SA · granted 2023-04-25.
US10442784B2
Composition: claim 1 combines a protein source with UA.
United States · applicant / assignee: Amazentis SA · granted 2019-10-15.
US9872850B2
Use: claim 1 concerns administering a urolithin to a mammal to enhance muscle performance.
United States · applicant / assignee: Amazentis SA · granted 2018-01-23.
As reviewed on 2026-10-25, Google Patents lists these US grants as Active. This records the database status, not an independent legal determination of validity, enforceability or current maintenance fees. Rights in Japan, Vietnam and other jurisdictions have not been assessed here. Patent scope depends on the granted claims and jurisdiction, not the title alone.
A patent protects a claimed invention; it does not prove clinical efficacy or imply exclusive ownership of every use of urolithin A. Mitopure® is a trademark. Research evidence, intellectual property and product adoption are separate questions. Inclusion in LÍFSVARÐA Knowledge does not indicate use or planned use in a LÍFSVARÐA product.
LITERATURE MAP / 10 PAPERS
Compare papers by conditions and findings.
A map focused on direct UA supplementation trials, comparing muscle function, pharmacokinetics, immunity, exercise and populations with disease. Gut microbial metabotype studies are distinguished from supplementation trials.
Selected: 2026-09-21. Bibliographic information checked against Europe PMC / PubMed. Editorial selection considered major papers and a range of populations and questions. This is not a systematic search covering all recent research.
10 RECORDS
A dash marks fields outside the bibliographic record. Use detailed records to compare findings and design records to connect mechanisms.
No papers match. Change the search conditions.
The literature map is an index of research questions and references. Individual assessment of results, doses, funding and COI is limited to the detailed study records. Related reports from the same trial may be included; paper counts are not counts of independent trials.
Explore the research Study Records
Listed doses describe study conditions, not recommended intake.
Urolithin A improves muscle strength, exercise performance, and biomarkers of mitochondrial health in a randomized trial in middle-aged adults.
PubMed 35584623DOI: 10.1016/j.xcrm.2022.100633
- Authors
- Singh A, D'Amico D, Andreux PA, Fouassier AM, Blanco-Bose W, Evans M, Aebischer P, Auwerx J, Rinsch C.
- Journal
- Cell reports. Medicine
- Publication year
- 2022
- Study design
- Randomized placebo-controlled trial
- Participants
- 88 sedentary middle-aged adults with overweight; 79 completed the trial.
- Dose and intervention
- Urolithin A 500 mg/day or 1,000 mg/day versus placebo.
- Duration
- 4 months
- Outcomes and their role in the study
- Primary: peak power. Strength, aerobic capacity and other measures were also assessed.
- Findings
- Hamstring strength improved versus placebo at 500 and 1,000 mg/day after 4 months. The primary peak-power outcome did not differ significantly. Walking-distance and aerobic-capacity changes included within-group improvements, not statistically significant superiority over placebo.
- Limitations
- Secondary strength findings were positive, while the primary peak-power outcome was not significant. Walking and aerobic measures included within-group changes rather than significant superiority to placebo. The trial was small, sponsor-funded and limited to 4 months.
- Funding
- Amazentis SA.
- Conflict of Interest
- Authors included sponsor employees, officers and scientific advisers.
- Scope of source review
- Relevant primary methods, endpoint hierarchy, timepoints, results, safety and disclosures checked on 2026-10-24. Secondary and within-group findings are distinguished from primary between-group outcomes.
Effect of Urolithin A Supplementation on Muscle Endurance and Mitochondrial Health in Older Adults: A Randomized Clinical Trial.
PubMed 35050355DOI: 10.1001/jamanetworkopen.2021.44279
- Authors
- Liu S, D'Amico D, Shankland E, Bhayana S, Garcia JM, Aebischer P, Rinsch C, Singh A, Marcinek DJ.
- Journal
- JAMA network open
- Publication year
- 2022
- Study design
- Randomized, double-blind, placebo-controlled trial
- Participants
- 66 adults aged 65–90, mean age 71.7; approximately 76% women, all White.
- Dose and intervention
- Urolithin A 1,000 mg/day
- Duration
- 4 months
- Outcomes and their role in the study
- Primary: six-minute walk distance and maximal ATP production in hand skeletal muscle. Secondary: muscle endurance and other measures.
- Findings
- Secondary hand and leg muscle endurance improved versus placebo at 2 months; selected blood markers improved at 4 months. Neither primary outcome—6-minute walk distance or maximal ATP production—showed a significant between-group benefit at 4 months.
- Limitations
- The muscle findings are encouraging but endpoint-specific. Small samples, short follow-up and limited independent replication constrain confidence. In the older-adult trial, the endurance advantage was not statistically significant at 4 months. Neither study establishes a longer human lifespan.
- Funding
- Amazentis SA. Involvement in design, conduct, analysis, manuscript preparation and publication decisions was described.
- Conflict of Interest
- Authors included sponsor employees, officers, shareholders and individuals with patent-related interests. See the original disclosures.
- Scope of source review
- Relevant primary methods, endpoint hierarchy, timepoints, results, safety and disclosures checked on 2026-10-24. Secondary and within-group findings are distinguished from primary between-group outcomes.
Cite this page
Urolithin A: muscle function, mitophagy and the research behind Mitopure®. LÍFSVARÐA. Version 2.0 / Updated 2026-10-25.
https://lifsvarda.com/knowledge/urolithin-a/Edited by LÍFSVARÐA (product brand).Editorial policy
Sources and updates
- Liu S, D'Amico D, Shankland E, Bhayana S, Garcia JM, Aebischer P, Rinsch C, Singh A, Marcinek DJ. (2022). Effect of Urolithin A Supplementation on Muscle Endurance and Mitochondrial Health in Older Adults: A Randomized Clinical Trial.Relevant primary methods, endpoint hierarchy, timepoints, results, safety and disclosures checked on 2026-10-24. Secondary and within-group findings are distinguished from primary between-group outcomes.
- Singh A, D'Amico D, Andreux PA, Fouassier AM, Blanco-Bose W, Evans M, Aebischer P, Auwerx J, Rinsch C. (2022). Urolithin A improves muscle strength, exercise performance, and biomarkers of mitochondrial health in a randomized trial in middle-aged adults.Relevant primary methods, endpoint hierarchy, timepoints, results, safety and disclosures checked on 2026-10-24. Secondary and within-group findings are distinguished from primary between-group outcomes.
2026-10-25 · Version 2.0: Expanded the muscle-evidence summary, mechanism, safety, research history and representative US patent examples; added an outcome-specific evidence profile. Central trial methods, results and disclosures and the 2026 synthesis were checked. Historical entries below are retained.
First published: 2026-09-21 / Version 1.1. Updated 2026-09-23: Added a research comparison table and links to design records. Source notes identify the scope of verification when the full paper has not been reviewed. Research summaries and LÍFSVARÐA’s interpretation are distinguished.