What are urolithins? Urolithins are gut-derived metabolites produced when certain polyphenols — especially ellagitannins from pomegranate — are transformed by gut bacteria. Among them, Urolithin A is the most studied and has been shown to support mitochondrial function, muscle health, and anti-aging signaling ¹.

These bioactives do not occur in food directly — they must be synthesized in the colon by a healthy microbiome. That makes dietary precursors (like punicalagins from pomegranate) crucial.

• Mitochondrial renewal: Urolithin A stimulates mitophagy, a cleanup process that removes damaged mitochondria
• Anti-inflammatory effects: Urolithins reduce NF-κB signaling and systemic inflammation markers
• Gut-mitochondria axis: Their benefits begin in the colon and extend systemically, especially in aging, fatigue, and gut permeability

Unlike most polyphenols, urolithins are the active metabolites — meaning the benefits rely on microbial transformation rather than direct absorption.

• Consume 1 tbsp of high-polyphenol pomegranate concentrate daily
• Maintain gut health with fiber and fermented foods to nourish urolithin-producing bacteria
• Support the gut–mitochondria axis by combining pomegranate with olive oil polyphenols

Some individuals are “non-producers,” but long-term intake of polyphenol-rich foods may shift the microbiota toward urolithin production ².

Urolithins are postbiotic molecules created by your microbiome — and they are essential to mitochondrial renewal and long-term vitality. If you’re wondering what are urolithins, they are powerful metabolites that arise when your body properly digests polyphenols like punicalagins. They activate mitochondrial renewal and reduce systemic inflammation, making them one of the most promising targets for functional aging and fatigue.

Tip: Feed your gut what it needs — and it will reward you with urolithins, your internal biological rejuvenators.