Learn what urolithins are, what they do and where you get them with MNB’s quick guide to nutraceuticals.
What are urolithins?
Urolithins are a type of antioxidant that can prevent damage to the proteins in our cells, protect our DNA and interact with a variety of cellular processes. They are made from tannins, a type of polyphenol micronutrient that we get from food. Polyphenols are amazing chemicals that plants use to protect themselves from all manner of damage. One of their main functions is to act as a natural sunscreen, protecting them from UV damage while allowing them to soak up the sun’s rays to make food. In addition to their powerful DNA protecting properties, they also help plants to fight off disease and even recover from attacks by pests. Pomegranates, walnuts, strawberries and raspberries are all high in the tannin, ellagitannin, which is converted into ellagic acid and then to urolithins for us to use.
Unlike most nutrients we can’t simply eat a food rich in ellagic acid, digest it in our stomach, and absorb it into our body through the intestinal wall. Polyphenols have a chemical structure that prevents our cells from absorbing them. Instead we rely on our gut microbiome to break them down into a bioavailable form. The bugs living in our intestines feast on the parts of plants we can’t digest – we give them safe shelter and sustenance in exchange for them converting indigestible molecules into nutrients our cells can take up and use.
Can I get urolithins by eating more pomegranate?
Frustratingly, no. humans need bacteria in our intestines to convert ellagic acid into a usable form. The amount of urolithin we can get from food is decided by the quantity of ellagic acid eating bugs living in our gut. Some people have lots of microbes that love to chow down on tannins and can access a ton of urolithin. Others have a different microbiome composition and barely gain any benefit from eating ellagic acid rich foods.
What are urolithins good for?
So far, lab tests on cell culture and animal models have shown that urolithins have the potential to:
- Keep our skin looking fresh
- keep our hearts healthy
- Reduce inflammation
- Get rid of faulty mitochondria
- Help to beat microbial infections
- Keep our brains healthy
- Help some cancer drugs to work better
How can I get more urolithin in my diet?
At the moment the best way to get more urolithins is through supplement pills. Chemists have discovered a way to extract them from tannins and make them into a form we can directly absorb. Another avenue, in development now, is prebiotics. Antioxidant researchers are trying to find out which types of bacteria are the best at converting polyphenols into urolithins, but it could be some time before we see ellagic acid prebiotics that really work on our shelves.
If you are lucky enough to have a microbiome that loves ellagic acid you can find it in:
- Pomegranate juice, skin, bark
- Red berries, for example strawberries, raspberries, cloud berrries, black berries
- Walnuts
- Pecans
Sources
Dini I, Grumetto L. Recent Advances in Natural Polyphenol Research. Molecules. 2022;27(24):8777. doi:10.3390/molecules27248777
Francisco M, Mendes F, Martins D, Liberal J. Unveiling the Anticancer Potential of Urolithin A in Colorectal Cancer: A Systematic Review. Oncol Res. 2026;34(2):3. doi:10.32604/or.2025.070276
Mihaylova R, Elincheva V, Momekov G, Simeonova R. Unlocking the Therapeutic Potential of Ellagitannins: A Comprehensive Review of Key Representatives. Molecules. 2025;30(22):4328. doi:10.3390/molecules30224328
Tomás-Barberán FA, González-Sarrías A, García-Villalba R, et al. Urolithins, the rescue of “old” metabolites to understand a “new” concept: Metabotypes as a nexus among phenolic metabolism, microbiota dysbiosis, and host health status. Mol Nutr Food Res. 2017;61(1). doi:10.1002/mnfr.201500901
