Urolithin A Foods: Pomegranate, Walnuts and Why Not Everyone Makes It

No food contains urolithin A itself. Pomegranates, walnuts and strawberries contain ellagitannins and ellagic acid, and your gut bacteria turn those into urolithin A. How well that works depends on your gut: in human trials, some people make only urolithin A, some make it alongside other urolithins, and 5 to 25 percent make none at all, whatever they eat.

Key Takeaways

• Urolithins are made by gut bacteria from ellagitannins and ellagic acid in foods such as pomegranates, walnuts and strawberries (García-Villalba et al., 2022).
• People fall into three groups: urolithin A only (25 to 80 percent of volunteers across trials), urolithin A plus other urolithins (10 to 50 percent), and no urolithins detected (5 to 25 percent) (Tomás-Barberán et al., 2014).
• Those groups held regardless of age, sex, body mass index or the amount of ellagitannin food eaten.
• Urolithin A taken directly was safe and reached the blood at every dose tested in older adults (Andreux et al., 2019).
• In middle-aged adults, 4 months of urolithin A improved muscle strength by about 12 percent (Singh et al., 2022).

What Is Urolithin A?

Urolithin A is a compound your gut bacteria make from plant polyphenols called ellagitannins and from ellagic acid. It is studied because it supports mitophagy, the process cells use to clear out and replace worn-out mitochondria, the parts that make energy. Thirteen urolithins have been described so far, and urolithin A is the one most studied (García-Villalba et al., 2022). Our guides to urolithin A benefits and mitophagy cover the science, and our urolithin A ingredient page has the basics.

Urolithin A Foods: Where the Building Blocks Come From

These foods supply the ellagitannins and ellagic acid your gut turns into urolithin A:

Food	Easy ways to eat it
Pomegranate	Arils on yogurt or salads, or 100 percent pomegranate juice
Walnuts	A small handful as a snack or on oatmeal
Strawberries	Fresh or frozen, in smoothies or with breakfast

Pomegranates, walnuts and strawberries are the examples researchers name (García-Villalba et al., 2022). They are worth eating for many reasons, and our list of anti-inflammatory foods includes several of them. For other compounds people look for in food, see our guides to resveratrol foods and NMN foods.

Why Not Everyone Makes Urolithin A

The step from food to urolithin A happens in your gut, and it depends on which bacteria live there. Across several human intervention trials, volunteers fell into three consistent groups, called metabotypes (Tomás-Barberán et al., 2014):

Metabotype	What they make	Share of volunteers
A	Urolithin A only	25 to 80 percent
B	Urolithin A plus isourolithin A or urolithin B	10 to 50 percent
0	No urolithins detected	5 to 25 percent

These groups showed up regardless of health status, age, sex, body mass index, or the amount or type of ellagitannin food eaten (Tomás-Barberán et al., 2014). In practice, eating more pomegranate will not turn a non-producer into a producer, and even producers make different amounts. That is the main reason urolithin A is also taken directly as a supplement. For more on how your gut and body talk to each other, see the gut-brain axis.

Urolithin A From Food vs a Supplement

	From food	As a supplement
How you get it	Your gut bacteria make it from ellagitannins	Urolithin A itself, no conversion needed
Who it works for	Producers only; 5 to 25 percent make none	Reached the blood at every dose tested
How much	Varies a lot from person to person	500 to 1,000 mg a day in human trials

The human trials so far gave urolithin A directly:

• First human trial: in healthy, sedentary older adults, urolithin A was safe, reached the blood at all doses, and 4 weeks at 500 mg or 1,000 mg a day changed blood and muscle markers of mitochondrial health (Andreux et al., 2019).
• Middle-aged adults: in a placebo-controlled trial at two daily doses for 4 months, muscle strength improved by about 12 percent, along with aerobic endurance and walking test results (Singh et al., 2022).
• Older adults: in 66 adults aged 65 to 90, 1,000 mg a day for 4 months improved muscle endurance in hand and leg muscles at 2 months compared with placebo, and side effects were no different from placebo (Liu et al., 2022).

Urolithin A, Spermidine and NAD+

Urolithin A is often paired with spermidine, which supports autophagy, the cell's general recycling process, while urolithin A targets mitochondria specifically. See spermidine benefits and autophagy. NAD+ works alongside both as the coenzyme cells use to turn food into energy; see NAD+ boosters and our cellular energy and mitochondria guide. For how urolithin A and NMN differ, see our guide to urolithin A vs NMN. For what spermidine studies measured on hair, see our guide to spermidine for hair growth.

Coming Soon: Our Urolithin A + Spermidine Capsules

Our Urolithin A + Spermidine Capsules are planned with urolithin A 500 mg and spermidine 6 mg per 2 capsules, the urolithin A amount used in human trials, with spermidine from a gluten-free source rather than wheat germ. They are coming soon; join the waitlist on the product page to hear when they launch, and no payment is taken. In the meantime, our Enhanced NMN supports cellular energy with 750 mg of NMN per serving.

Frequently Asked Questions

What foods contain urolithin A?

None contain it directly. Pomegranates, walnuts and strawberries contain ellagitannins, which gut bacteria turn into urolithin A.

Can you get enough urolithin A from food?

It depends on your gut bacteria. Some people make plenty, others make little, and 5 to 25 percent of people in trials made none, however much ellagitannin food they ate.

Is pomegranate juice a good source of urolithin A?

It is one of the richest sources of the building blocks, but how much urolithin A you make from it depends on your gut bacteria.

How do I know if I make urolithin A?

Only a lab test of urine or blood after eating ellagitannin foods can show it. Most people never find out, which is one reason some take urolithin A directly.

How much urolithin A should I take?

Human trials used 500 to 1,000 mg a day. Follow the label of the product you use.

Is urolithin A safe?

In trials lasting up to 4 months, it was well tolerated, and side effects were no different from placebo in older adults. Talk with your clinician first if you are pregnant, breastfeeding or take prescription medicine.

Do walnuts have urolithin A?

Walnuts contain ellagitannins, not urolithin A itself. Your gut bacteria can convert them if you are a producer.

Can you take urolithin A with spermidine?

Yes. They support different parts of cell renewal, mitophagy and autophagy, and are often taken together.

Sources

• García-Villalba R, et al. Urolithins: a comprehensive update on their metabolism, bioactivity, and associated gut microbiota. Molecular Nutrition and Food Research, 2022. https://pubmed.ncbi.nlm.nih.gov/35118817/
• Tomás-Barberán FA, et al. Ellagic acid metabolism by human gut microbiota: consistent observation of three urolithin phenotypes in intervention trials, independent of food source, age, and health status. Journal of Agricultural and Food Chemistry, 2014. https://pubmed.ncbi.nlm.nih.gov/24976365/
• Andreux PA, et al. The mitophagy activator urolithin A is safe and induces a molecular signature of improved mitochondrial and cellular health in humans. Nature Metabolism, 2019. https://pubmed.ncbi.nlm.nih.gov/32694802/
• Singh A, et al. Urolithin A improves muscle strength, exercise performance, and biomarkers of mitochondrial health in a randomized trial in middle-aged adults. Cell Reports Medicine, 2022. https://pubmed.ncbi.nlm.nih.gov/35584623/
• Liu S, et al. Effect of urolithin A supplementation on muscle endurance and mitochondrial health in older adults: a randomized clinical trial. JAMA Network Open, 2022. https://pubmed.ncbi.nlm.nih.gov/35050355/

These statements have not been evaluated by the Food and Drug Administration. This content is for education and is not medical advice. Our products are not intended to diagnose, treat, cure or prevent any disease. Talk with a healthcare provider before starting a new supplement if you are pregnant, breastfeeding or taking medication.