By the Mito Renewal Editorial Team · Last updated 5 July 2026
In the human clinical trials published to date, Urolithin A has been reported as safe and well tolerated, including in older adults over four months of daily use. As with any supplement, that's not a guarantee for every individual, and some sensible precautions apply. Here's an honest summary.
What the safety research says
The first-in-human study of Urolithin A (Nature Metabolism, 2019) was designed primarily to assess safety, and reported a favourable safety profile at doses including 500mg and 1000mg. A later randomised trial in adults aged 65–90 (JAMA Network Open, 2022) reported it was safe and well tolerated over four months. This is a relatively strong safety record for a supplement ingredient, though the studies are still limited in size and length.
Possible side effects
Reported side effects have generally been minimal. As with many supplements, some people may notice mild digestive changes when first starting. If anything feels off, stop and check with your healthcare provider.
Who should check with a doctor first
Speak with your doctor or pharmacist before starting Urolithin A if you are pregnant or breastfeeding, taking prescription medication, or managing an existing health condition. Urolithin A is not known to interact with common medications, but individual circumstances vary, and your own clinician is the right person to advise you. Our article on who should and shouldn't take Urolithin A covers this in more depth.
Sensible ways to reduce risk
- Start at the dose on your product label rather than exceeding it.
- Take it with food, which many people find easier on the stomach.
- Introduce one new supplement at a time so you can tell how you respond.
- Keep your healthcare provider informed about supplements you take.
The bottom line
Urolithin A has a reassuring safety record in the research so far, but “well tolerated in trials” is not the same as “right for everyone.” Use it sensibly, and treat your own doctor — not a product website — as the final word for your situation. For dosing, see our dosage guide; for the full picture, our complete guide to Urolithin A. Mito Renewal Complete provides 500mg per capsule.
References
- Andreux PA, et al. Nature Metabolism. 2019;1:595–603. Link
- “Effect of Urolithin A Supplementation on Muscle Endurance and Mitochondrial Health in Older Adults.” JAMA Network Open. 2022. Link
This article is for general education and is not medical advice. Mito Renewal Complete is a dietary supplement and is not intended to diagnose, treat, cure or prevent any disease. Consult your healthcare practitioner before starting any supplement. See our medical disclaimer.