Urolithin A Interactions: Alcohol, Caffeine, Food and Other Compounds in the Literature

Urolithin A is not a peptide and not a plant compound taken directly from food. It is a metabolite: gut bacteria convert ellagitannins and ellagic acid — found in pomegranate, walnuts and some berries — into urolithins, and only a subset of people carry microbiota capable of producing meaningful amounts. That origin story shapes every interaction question on this page, because anything that changes the gut microbiome, gut transit, or hepatic conjugation could in principle change urolithin A exposure. Whether it actually does has largely not been tested in controlled human interaction studies.

This page is for educational purposes only and is not medical advice; consult a licensed physician about anything relating to your own health. It summarises what published studies examined, and states plainly where no interaction study exists.

What Counts as an Interaction Study — and What Does Not

A true interaction study administers two agents, alone and together, and measures either pharmacokinetics (blood levels, exposure, clearance) or a shared endpoint. Searching the published urolithin A literature, that design is largely absent for alcohol, caffeine, and common supplements. What does exist falls into three weaker categories:

• Co-administration inside a disease model. Animals were given a toxin or challenge (for example ethanol) plus urolithin A, and outcomes were measured. This shows an effect on the injury, not a pharmacokinetic interaction.
• Combination with a drug in cancer models. Cells or animals received urolithin A alongside a chemotherapeutic, and researchers measured tumour or transporter endpoints.
• Formulation and administration details in human trials. Trials describe how the compound was given, which hints at food effects without testing them.

Below, each interaction topic is labelled as either studied or mechanistic reasoning only.

Urolithin A and Alcohol: What Studies Report

Status: studied in animal models of alcohol-associated liver disease, not as a pharmacokinetic interaction in humans.

Two published reports examined urolithin A in the context of chronic alcohol exposure. A 2024 study in Gut Microbes reported that urolithin A alleviated chronic alcohol-related liver disease through a gut-microbiota–liver axis, identifying MUP1 as a mediator of the effect (https://pubmed.ncbi.nlm.nih.gov/38889450/). A 2025 report in Frontiers in Pharmacology similarly described urolithin A regulating the gut–liver axis to ameliorate alcohol-associated liver disease (https://pubmed.ncbi.nlm.nih.gov/41635923/).

Two points matter for how these are read. First, both examined urolithin A as an intervention against alcohol-induced injury in a disease model — they did not measure whether alcohol changes urolithin A blood levels, or whether urolithin A changes blood alcohol or acetaldehyde handling. Second, findings in rodent liver-injury models are not statements about what happens in people who drink socially. The 2024 Gut Microbes work is notable mechanistically because it located the effect in the gut-microbiota–liver axis rather than in the liver alone (https://pubmed.ncbi.nlm.nih.gov/38889450/), and the microbiome is precisely the compartment alcohol is known to disturb.

The mechanistic reasoning researchers use (labelled as reasoning, not data)

Because urolithin A is produced by gut bacteria from dietary precursors, and because heavy alcohol intake alters gut bacterial composition and intestinal permeability, researchers reason that alcohol could in principle reduce endogenous urolithin production in people who rely on their own microbiota rather than a direct supply of the metabolite. No published study has measured that conversion capacity before and after alcohol exposure in humans. That gap should be read as a gap, not as evidence of absence of an interaction — and equally not as evidence that one occurs.

Urolithin A and Caffeine

Status: no published interaction study.

No trial in the verified literature administered urolithin A with caffeine, coffee, or tea and measured either compound's pharmacokinetics or a shared endpoint. Statements online pairing the two are not supported by published co-administration data.

The mechanistic reasoning sometimes offered — again, reasoning rather than measurement — runs through overlapping cellular targets. Urolithin A's best-characterised action is the induction of mitophagy, the selective recycling of damaged mitochondria, which was the mechanism examined in a 2023 Nature Aging study reporting that induction of mitochondrial recycling reverted age-associated decline of the haematopoietic and immune systems (https://pubmed.ncbi.nlm.nih.gov/37653255/). Caffeine is an adenosine receptor antagonist with its own reported influences on autophagy signalling in preclinical work. Whether those pathways converge, oppose, or simply run in parallel at ordinary dietary caffeine intakes has not been tested alongside urolithin A in any published study, and no dose relationship between the two has been established.

Food, Fasting and Absorption

Status: partially informed by how trials administered the compound; no dedicated food-effect study.

The most informative human data point is the randomised clinical trial published in JAMA Network Open in 2022, which evaluated urolithin A supplementation on muscle endurance and mitochondrial health in older adults (https://pubmed.ncbi.nlm.nih.gov/35050355/). That trial used oral supplementation over a defined period and reported on muscle endurance and mitochondrial endpoints; it was not designed as a fed-versus-fasted comparison, so it cannot answer whether food changes absorption.

A 2024 review in Sports Medicine discussing mitochondria as nutritional targets to maintain muscle health and physical function during ageing placed urolithin A within the broader category of nutritional mitochondrial interventions (https://pubmed.ncbi.nlm.nih.gov/39060742/). Reviews of that kind summarise the field; they do not supply food-effect pharmacokinetics.

Why the food question is unusually complicated here

For most compounds, a food-effect study is straightforward. For urolithin A it is layered:

1. Precursor route. When urolithin A arises from dietary ellagitannins, food is not a modifier of absorption — food is the source, and the rate-limiting step is bacterial conversion, which varies widely between individuals.
2. Direct route. When the metabolite itself is administered, the relevant variables become solubility, formulation and first-pass conjugation in the gut wall and liver, where urolithin A is extensively converted to glucuronide and sulfate forms.
3. Fasting states. Fasting alters both gut transit and autophagy tone. Because urolithin A's reported effects run through mitophagy (https://pubmed.ncbi.nlm.nih.gov/37653255/), researchers have speculated about additive or redundant signalling with fasting, but no published trial has compared urolithin A administration in fasted versus fed humans on mitophagy endpoints.

Combinations With Drugs and Other Compounds

Chemotherapy: the one studied combination

The clearest published example of urolithin A combined with a drug comes from oncology models. A 2022 Theranostics study reported that a microbial metabolite restricted 5-fluorouracil-resistant colonic tumour progression by sensitising drug transporters through regulation of the FOXO3–FOXM1 axis (https://pubmed.ncbi.nlm.nih.gov/35910798/). Transporter modulation is the mechanism most relevant to drug interactions generally, because transporters govern how much of a co-administered drug reaches its target. That said, the finding was generated in a cancer model with a specific chemotherapeutic, and researchers have not extended it to a general statement about drug handling in humans.

Neurotransmitter conjugates: chemistry, not co-administration

A 2025 paper in Biomedicine & Pharmacotherapy described the synthesis, characterisation and anti-inflammatory potential of serotonin- and dopamine-conjugates of urolithin A (https://pubmed.ncbi.nlm.nih.gov/40554288/). This is frequently miscited as evidence about urolithin A taken alongside serotonergic or dopaminergic agents. It is not: the researchers built new single molecules by chemically linking the structures, then tested those novel conjugates. Nothing in that work describes co-administering urolithin A with a separate serotonergic drug.

Circadian timing

A 2024 Nutrients study reported that urolithin A modulated PER2 degradation via SIRT1 and enhanced the amplitude of circadian clocks in human senescent cells (https://pubmed.ncbi.nlm.nih.gov/39796454/). This is cell-culture work on clock gene machinery. It is sometimes read as implying an optimal time of day for administration; the study examined clock amplitude in senescent cells and did not test administration timing in humans or compare morning versus evening dosing.

Summary Table: Studied Versus Not Studied

Tolerability in Combination Contexts: What Studies Report

Human tolerability information comes chiefly from the randomised trial in older adults, where researchers evaluated urolithin A supplementation against muscle endurance and mitochondrial health endpoints (https://pubmed.ncbi.nlm.nih.gov/35050355/). That trial was not designed to detect interactions with alcohol, caffeine, or concomitant medications, and participants in such trials are typically screened, so the results do not describe what happens in populations taking multiple agents. The animal alcohol-liver work reported outcomes on liver injury rather than on adverse events from the combination itself (https://pubmed.ncbi.nlm.nih.gov/38889450/). No published pharmacovigilance dataset in the verified literature characterises urolithin A adverse events during co-exposure to other substances.

Mechanism Recap: Why Interaction Questions Keep Arising

The breadth of urolithin A's reported biology is why interaction questions multiply. Beyond immune and haematopoietic ageing (https://pubmed.ncbi.nlm.nih.gov/37653255/), researchers reported that urolithin A promoted p62-dependent lysophagy in a model of acute retinal neurodegeneration (https://pubmed.ncbi.nlm.nih.gov/38890703/) and that it suppressed high-glucose-induced neuronal amyloidogenesis by modulating TGM2-dependent ER–mitochondria contacts and calcium homeostasis (https://pubmed.ncbi.nlm.nih.gov/32704090/). Related work on the mitochondrial fission–mitophagy axis in diabetes-associated cognitive dysfunction (https://pubmed.ncbi.nlm.nih.gov/38102662/) and on mitochondrial quality-control machinery in neurodevelopment (https://pubmed.ncbi.nlm.nih.gov/42490384/) illustrates how central and widely shared mitophagy regulation is. A pathway that general intersects, on paper, with many other interventions — which is exactly why mechanistic overlap should not be mistaken for a demonstrated interaction.

How to Read Interaction Claims You Encounter

• Check the species and design. A rodent liver-injury model answers a different question than a human pharmacokinetic study (https://pubmed.ncbi.nlm.nih.gov/41635923/).
• Distinguish conjugates from combinations. Chemically linked molecules are new entities, not two compounds taken together (https://pubmed.ncbi.nlm.nih.gov/40554288/).
• Distinguish mechanism from outcome. Shared pathway involvement, such as mitophagy induction (https://pubmed.ncbi.nlm.nih.gov/37653255/), predicts nothing on its own about net effect.
• Treat silence as silence. Where no study exists — as with caffeine — the honest description is that the question is open.

For background on the compound itself, its origin from dietary ellagitannins, and the trials that have examined it, see the urolithin A learn page.

References

• Urolithin A promotes p62-dependent lysophagy to prevent acute retinal neurodegeneration (Molecular Neurodegeneration, 2024)
• Induction of mitochondrial recycling reverts age-associated decline of the hematopoietic and immune systems (Nature Aging, 2023)
• Effect of Urolithin A Supplementation on Muscle Endurance and Mitochondrial Health in Older Adults: A Randomized Clinical Trial (JAMA Network Open, 2022)
• MUP1 mediates urolithin A alleviation of chronic alcohol-related liver disease via gut-microbiota-liver axis (Gut Microbes, 2024)
• Mitochondria as Nutritional Targets to Maintain Muscle Health and Physical Function During Ageing (Sports Medicine, 2024)
• HUWE1 targets mitochondria via RMC1 to promote neurodevelopment (PNAS, 2026)
• Urolithin A suppresses high glucose-induced neuronal amyloidogenesis by modulating TGM2-dependent ER-mitochondria contacts and calcium homeostasis (Cell Death and Differentiation, 2021)
• Urolithin A Modulates PER2 Degradation via SIRT1 and Enhances the Amplitude of Circadian Clocks in Human Senescent Cells (Nutrients, 2024)
• Neuron-targeted overexpression of caveolin-1 alleviates diabetes-associated cognitive dysfunction via regulating mitochondrial fission-mitophagy axis (Cell Communication and Signaling, 2023)
• Synthesis, characterization, and anti-inflammatory potential of serotonin- and dopamine-conjugates of urolithin A (Biomedicine & Pharmacotherapy, 2025)
• Urolithin A regulates gut: liver axis to ameliorate alcohol-associated liver disease (Frontiers in Pharmacology, 2025)
• Microbial metabolite restricts 5-fluorouracil-resistant colonic tumor progression by sensitizing drug transporters via regulation of FOXO3-FOXM1 axis (Theranostics, 2022)