Your body does not make Urolithin A directly. Instead, it depends on gut microbes that convert ellagitannins from foods like pomegranate, walnuts, and some berries into this postbiotic compound. Urolithin A has drawn attention because of its ability to support mitochondrial renewal, a process tied to cellular energy, muscle function, and healthy aging. But what is the best source of Urolithin A — food or supplementation? Let’s explore the science.

Urolithin A Sources: What the Research Shows

Urolithin A is produced only after microbial conversion of ellagitannins. Foods rich in these precursors include pomegranate, walnuts, raspberries, and strawberries. However, a person’s microbiome determines whether those precursors will actually be transformed. Researchers have defined urolithin metabotypes to classify these differences: some people produce high amounts of Urolithin A (UM-A), others produce Urolithin B or isourolithin A (UM-B), and some produce none at all (UM-0). This variability explains why two people can eat the same pomegranate but experience very different Urolithin A levels. A review in Molecular Nutrition & Food Research highlighted that as many as 40 percent of adults may be low or non-producers.

Pomegranate is the most widely studied whole food source. Importantly, studies show that the peel contains the highest concentration of ellagitannins, particularly punicalagin, which supplies the raw material for Urolithin A production. Reviews in Food Chemistry and Frontiers in Pharmacology have reported that pomegranate peel consistently has more than double the phenolic content compared with arils or juice. This makes the peel an attractive source for supplements that aim to deliver reliable Urolithin A levels.

Food Versus Supplements: Reliability and Consistency

Diet-first is always a sound approach, but the challenge is consistency. A randomized crossover study published in the European Journal of Clinical Nutrition in 2022 compared a single serving of 100 percent pomegranate juice with a standardized 500 mg Urolithin A supplement in healthy adults. The results were striking: supplementation produced more than six times the plasma exposure to circulating Urolithin A over 24 hours compared to juice. Furthermore, only about 40 percent of participants reached meaningful circulating levels after juice, highlighting how much microbiome variability limits natural production.

This means that even if you consume ellagitannin-rich foods, your microbiome may not convert enough to deliver measurable benefits. Direct supplementation bypasses this variability by delivering Urolithin A itself, ensuring consistent exposure across the population.

Why Consistency Matters

The clinical studies that show functional benefits from Urolithin A — including improvements in muscle endurance, strength, and mitochondrial biomarkers — have all used standardized supplementation. For example, a 2019 trial in Nature Metabolism demonstrated that four weeks of daily Urolithin A at 500 to 1,000 mg was safe and led to molecular signatures of improved mitochondrial function in older adults. A 2022 trial in JAMA Network Open found that four months of Urolithin A supplementation improved muscle endurance in adults aged 65 to 90 years, while another Cell Reports Medicine study reported better muscle strength and exercise performance in sedentary middle-aged adults over the same timeframe. These outcomes depend on reliable circulating Urolithin A, which is difficult to achieve with diet alone if your microbiome is not a strong producer.

When Food Still Makes Sense

Whole foods provide much more than ellagitannins. Pomegranates, walnuts, and berries supply fiber, vitamins, minerals, and a spectrum of polyphenols that support cardiometabolic health. Even if your microbiome is a weak Urolithin A converter, these foods still deliver important nutritional benefits. In fact, diet and supplements can work hand-in-hand: whole foods nourish your gut microbiome and overall health, while supplementation ensures consistent Urolithin A exposure to activate mitochondrial pathways.

Practical Tips for Choosing the Best Source

Start with diet: Incorporate pomegranate, walnuts, and berries for their broad nutritional value.

Know your microbiome: If you suspect you are a low or non-producer, supplementation can help you bypass conversion barriers.

Think long-term: The most compelling benefits have been observed after 8 to 16 weeks of steady intake, so plan for consistency rather than quick results.

Personalize your approach: Age, antibiotic use, and overall diet influence conversion. What works for one person may not work for another.

Work with a clinician: Especially if you manage chronic conditions or take medications, professional guidance ensures safe and effective integration.

Supporting Mitochondrial Health with BioLithin

BioLithin was developed with this science in mind. It combines Urolithin A, Urolithin B, and taurine, and sources its urolithins from pomegranate peel, the most efficacious portion of the plant for ellagitannins. By providing standardized doses of both Urolithin A and B, BioLithin delivers consistent mitochondrial support without relying on microbiome variability. Taurine further enhances mitochondrial function, helping to sustain energy, muscle resilience, and healthy aging.

BioLithin is available in single, two-pack, four-pack, and ten-pack options, with subscription savings for long-term use. Stored in Miron violet glass for potency, it represents a comprehensive approach to mitochondrial quality control.

Key Takeaway

Urolithin A is a powerful ally for mitochondrial health, but not everyone can produce it from food alone. While pomegranates and walnuts remain valuable dietary staples, the best way to ensure consistent levels is through standardized supplementation. By combining both strategies — whole-food nutrition and BioLithin — you can cover the variability of your microbiome while supporting energy, endurance, and healthy aging.

This content is for informational purposes only and is not a substitute for medical advice. Individual responses may vary, and research on Urolithin A is ongoing. Always consult with a healthcare professional before starting a new supplement regimen.