Urolithins and their Many Health Benefits

Urolithin A and B are natural polyphenol compounds found in fruits, such as pomegranates and berries, and walnuts.  These urolithins are both produced by gut bacteria.

Claims about Urolithin A include its effect on mitochondria, stimulating their proliferation to increase energy production. It also stimulates mitophagy, i.e. the elimination of senescent mitochondria that may be pro-inflammatory. Other purported benefits include increased muscle mass, strength, and endurance, and generalized anti-inflammatory effects. Urolithin A may also improve cognitive function and protect against neurodegenerative diseases, including Alzheimer’s disease. Given these benefits, Urolithin A is marketed as an anti-aging supplement. 

Urolithin B appears to have more impact on bone health and has anti-cancer activity and anti-inflammatory effects. Urolithin A is better absorbed and is more commonly taken as a dietary supplement. Urolithin A is sold as a dietary supplement that varies in price between $10 per month to over $100 per month at a dose of 500 mg per day.

Urolithin supplements are considered to be safe. Side-effects are generally absent or mild, and include GI upset and diarrhea.

Let’s look at the many health benefits of Urolithins: What do the research data show?

Urolithins have anti-cancer activity. They suppress proliferation and promote apoptosis of leukemic cells (https://pubmed.ncbi.nlm.nih.gov/34067305/). Urolithin A treatment has anti-cancer and anti-inflammatory action in various in vivo studies, including colitis rat model, carrageenan-induced paw edema mice model, models of pancreatic cancer, and models of obesity (https://pubmed.ncbi.nlm.nih.gov/35657053/). Urolithin A suppresses oral squamous cell tumor growth in vitro and in mice and may be active in prevention of this common malignancy (https://pmc.ncbi.nlm.nih.gov/articles/PMC10497365/).

There are also data supporting the anti-inflammatory effects of both Urolithin A and B, including in neuroinflammatory disorders associated with oxidative stress (https://pubmed.ncbi.nlm.nih.gov/30668443/).

Should we all take Urolithin supplements? Urolithins are polyphenol compounds, which are vital for human health. There are more than 8,000 types of polyphenols, including flavonoids (apples, onions, red cabbage), phenolic acids (coffee, whole grains), and others. Curcumin in tumeric, dark chocolate, tea, and berries are some of the best-known sources of polyphenols in our diet. Supplements rich in polyphenols include green tea extract (EGCG), curcumin, and quercitin.

We need to be selective about what supplements we choose, since most of us do not want to take dozens of supplements every day. We might be well-advised to consume lots of polyphenols in our diet and take 1 or 2 supplements rich in these valuable compounds, including Urolithin A.

Note: Although I am a physician, the content in this article is not meant to diagnose, treat, cure or prevent illness or disease in the reader – it is for educational purposes only.

References

1. Alzahrani AM, Mohammed MRS, Alghamdi RA, et al. Urolithin A and B Alter Cellular Metabolism and Induce Metabolites Associated with Apoptosis in Leukemic Cells. Int J Mol Sci 2021;22(11):5465. https://pubmed.ncbi.nlm.nih.gov/34067305/
2. Rogovskii VS. The Therapeutic Potential of Urolithin A for Cancer Treatment and Prevention. Curr Cancer Drug Targets 2022;22(9):717-24. https://pubmed.ncbi.nlm.nih.gov/35657053/
3. Remadevi V, Jaikumar VS, Vini R, et al. Urolithin A, induces apoptosis and autophagy crosstalk in Oral Squamous Cell Carcinoma via mTOR /AKT/ERK1/2 pathway. Phytomedicine. 2024 Jul 25;130:155721.
4. Lee G, Park JS, Lee EJ, Ahn JH, Kim HS. Anti-inflammatory and antioxidant mechanisms of urolithin B in activated microglia. Phytomedicine. 2019 Mar 01;55:50-57. https://pubmed.ncbi.nlm.nih.gov/30668443/