Urolithin A & Cellular Aging

Reviewed by SOMA HEALTH's Medical Research Team

Every cell you rely on is powered by mitochondria, and the way your body keeps those mitochondria in good repair changes as the years pass. Urolithin A has become one of the most closely studied compounds in this space because it targets a specific housekeeping process called mitophagy. This guide walks through what the human evidence actually shows about urolithin A and the cellular side of aging, what is still preclinical, and how to think about it without overstating the case.

What "cellular aging" actually describes

Aging is not one event. Researchers who study it often describe a set of interlocking cellular changes, sometimes called the hallmarks of aging, that tend to accumulate over a lifetime. These include the gradual buildup of damaged proteins, shifts in how cells sense nutrients, a rise in long-lived senescent cells that no longer divide, and, central to this page, a decline in mitochondrial quality. Mitochondrial dysfunction is one of the most consistently recognized hallmarks because mitochondria sit at the crossroads of energy production and cellular signaling.

Over time, cells tend to accumulate mitochondria that are worn, inefficient, or damaged. A worn mitochondrion produces less usable energy and can leak more reactive byproducts, which places additional strain on the cell. In a younger, well-functioning system, quality-control pathways clear these damaged units quickly. The concern with aging is that this clearance slows down, and the damaged mitochondria linger longer than they should.

Where mitophagy comes in

Mitophagy is the cell's targeted recycling program for mitochondria. It is a specialized form of autophagy that tags a worn or damaged mitochondrion, encloses it, and breaks it down so its parts can be reused and healthier mitochondria can take its place. You can think of it as routine maintenance on a fleet of tiny power plants: when maintenance keeps pace, the fleet stays efficient; when it lags, aging and inefficient units pile up. Supporting mitophagy is the mechanistic reason urolithin A is discussed in the context of cellular aging. For a deeper primer, see our explainer on what mitophagy is and our overview of mitochondrial health.

How urolithin A works

Urolithin A is a gut postbiotic. It is not found in meaningful amounts in food directly. Instead, your gut microbiome produces it from ellagitannins, the polyphenols abundant in pomegranates, walnuts, and certain berries. Here is the practical catch: only some people carry the gut bacteria needed to make this conversion efficiently. Estimates vary, but a substantial share of adults produce little urolithin A on their own even with a polyphenol-rich diet, which is a large part of why a standardized supplemental form became a research focus. In laboratory and human work, urolithin A has been studied for its ability to support mitophagy, encouraging the cell to recycle worn mitochondria.

What the human evidence shows

The most rigorous evidence for urolithin A comes from human clinical trials, and it is worth being precise about what they measured.

Safety and mitochondrial gene signature (human)

The first-in-human study, Andreux and colleagues in Nature Metabolism (2019), found urolithin A was safe and well tolerated at single doses up to 1,000 mg per day and, notably, shifted a mitochondrial gene-expression signature in the direction associated with better mitochondrial function. This is meaningful because it connected the mechanism seen in lab models to a measurable biological response in people.

Immune-cell mitochondrial health (human)

A more recent randomized controlled trial published in Nature Aging (2025) followed midlife adults over roughly 28 days and reported that urolithin A supported the mitochondrial health of immune cells, an area sometimes discussed under the heading of inflammaging, the low-grade shift in immune signaling that tends to accompany aging. This is one of the newer human datasets and it broadens the picture beyond muscle.

Muscle strength and endurance (human)

Two trials anchor the muscle evidence. Singh and colleagues (Cell Reports Medicine, 2022) studied middle-aged adults over four months using 500 mg and 1,000 mg daily arms and reported improvements in muscle strength and aspects of exercise performance. Liu, D'Amico and colleagues (JAMA Network Open, 2022) studied older adults over roughly four months and reported gains in muscle endurance. Muscle is relevant to cellular aging because skeletal muscle is densely packed with mitochondria and is one of the tissues where age-related mitochondrial decline is most visible. Additional trials in resistance-trained men (Journal of the International Society of Sports Nutrition, 2024) and distance runners (2025) extend the performance picture in younger, active populations. You can read the full breakdown on our clinical studies page.

An important honesty note: these human trials measured function and specific biomarkers, not a person's "cellular age" as a single number. They support the idea that urolithin A can influence mitochondrial function in people, which is the pathway of interest, but they do not measure aging itself.

What is still preclinical

Much of the mitophagy-and-longevity story began in the lab, and that work should be labeled as such. Ryu and colleagues (Nature Medicine, 2016) showed that urolithin A induced mitophagy, extended lifespan in the worm C. elegans, and improved muscle measures in rodents. This preclinical work is genuinely important because it established the mechanism, but effects on lifespan in a worm do not translate directly to humans. Separately, D'Amico and colleagues (Aging Cell, 2022) reported joint and cartilage effects in osteoarthritis models, again preclinical. Explorations of skin, gut, brain, and heart remain at the early or preclinical stage, so the honest framing is that early research is exploring these areas rather than that benefits are established.

An honest read on the limitations

A 2024 systematic review in Ageing Research Reviews, focused on targeting aging with urolithin A in humans, concluded that the evidence is still emerging. That is the accurate summary. Urolithin A is not a way to reverse the clock, and no supplement can claim to stop aging. What the science supports is narrower and more useful: urolithin A can support a specific, well-defined cellular maintenance process. Individual response also varies, partly because natural production from food differs so widely between people. Aging is a normal biological process rather than a condition to be fixed, and if you have specific health concerns about aging, muscle loss, or mitochondrial conditions, this guide is not a treatment plan and you should speak with your doctor.

Practical guidance

Human trials have used 500 to 1,000 mg per day, with 1,000 mg representing the top of the studied range. Because mitophagy is a maintenance process rather than an acute stimulant, consistency over weeks and months matters more than any single dose, and the trials that reported functional changes ran for roughly four months. Taking it with a meal is a reasonable habit. For a full walkthrough of the science and how to start, see our urolithin A guide, and if you are comparing products, our roundup of the best urolithin A gummies lays out what to look for.

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. This guide is educational and is not a substitute for advice from a qualified healthcare provider.