Comparison
Spermidine vs Urolithin A
Side-by-side of Spermidine and Urolithin A. Every row below is pulled from the compound schema and will update as our data grows. For deeper reads, follow through to each compound page.
Spermidine
Spermidine supplement benefits cover autophagy induction, longevity signals, and cognition. Wheat germ extract data, doses, and human trials reviewed.
Urolithin A
Urolithin A supplement guide: pomegranate-derived metabolite, 500-1000 mg Mitopure dosing, mitophagy and muscle endurance evidence.
Effects at a glance
Spermidine
- •Endogenous polyamine that induces autophagy via EP300 acetyltransferase inhibition and TFEB activation
- •Concentrated in wheat germ, soybeans, aged cheese, and mushrooms; ~10 to 15 mg/day in Mediterranean diets
- •Eisenberg 2016 reported dietary spermidine extended mouse lifespan and improved cardiac function
- •Wirth 2018 pilot (n=28) reported cognitive signal at 0.9 mg/day in older adults at risk for dementia
- •Larger Wirth 2019 follow-up (n=85) did not replicate the memory benefit at 12 months
- •Generally regarded as safe at supplemental doses; food-source position is reassuring
Urolithin A
- •Gut-microbiome-derived metabolite of pomegranate and walnut ellagitannins
- •Roughly 40% of adults are 'urolithin producers' from dietary intake; ~60% are non-producers
- •Ryu 2016 (Nature Medicine) reported lifespan extension in C. elegans and muscle benefits in aged rodents
- •Andreux 2019 first-in-human trial (n=60) established safety and mitochondrial gene-expression upregulation
- •Singh 2022 (n=66, 4 months, 1000 mg/day) reported improved muscle endurance in older adults
- •Most human trial portfolio is Amazentis-funded; independent replication is thin
Side-by-side
| Attribute | Spermidine | Urolithin A |
|---|---|---|
| Category | supplement | supplement |
| Also known as | spermidine trihydrochloride, wheat-germ-extract spermidine | UA, Mitopure, ellagitannin metabolite |
| Half-life (hr) ↗ | 6 | 17 |
| Typical dose (mg) ↗ | 1.2 | 500 |
| Dosing frequency | daily, typically morning with food | daily, morning with food |
| Routes | oral | oral |
| Onset (hr) | 2 | 2 |
| Peak (hr) | 4 | 4 |
| Molecular weight | 145.25 | 228.2 |
| Molecular formula | C7H19N3 | C13H8O4 |
| Mechanism | Induces macroautophagy via inhibition of EP300 histone acetyltransferase and activation of TFEB-mediated lysosomal biogenesis. Substrate for hypusination of eIF5A, required for translation of mitochondrial respiration proteins. | Induces mitophagy via potentiation of PINK1/Parkin signaling, leading to selective degradation of damaged mitochondria. Secondary anti-inflammatory effects via NF-kB modulation. |
| Legal status | OTC dietary supplement (wheat-germ extract has GRAS status in US) | OTC dietary supplement (US GRAS 2018; EFSA Novel Food 2021) |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement (not scheduled) | OTC supplement (not scheduled) |
| Pregnancy | Insufficient data; not routinely recommended at supplemental doses | Insufficient data; not routinely recommended |
| CAS | 124-20-9 | 1143-70-0 |
| PubChem CID | 1102 | 5488186 |
| Wikidata | Q411089 | Q27101321 |
Safety profile
Spermidine
Common side effects
- mild GI upset (rare)
- headache (rare)
Contraindications
- wheat-germ allergy or celiac disease (for wheat-germ-extract products)
- active cancer (theoretical)
- pregnancy and lactation (insufficient data)
Interactions
- DFMO (difluoromethylornithine): competing polyamine metabolism; do not combine without oncology guidance(moderate)
Urolithin A
Common side effects
- mild GI upset (rare)
- soft stools (rare)
Contraindications
- pregnancy and lactation (insufficient data)
- active chemotherapy (consult oncology)
Interactions
- chemotherapy agents: theoretical interaction with mitochondrial-targeting agents; consult oncologist(moderate)
Which Should You Take?
Urolithin A comes out ahead for most readers on the criteria we weight: 3 catalogued goals, OTC dietary supplement, oral dosing, with a Tier-A outcome catalogued. Spermidine is the right call when one of the conditionals below applies.
- → If your priority is focus or working memory, pick Spermidine.
- → If your priority is muscle hypertrophy, pick Urolithin A.
- → If your priority is mitochondrial function, pick Urolithin A.
Default choice: Urolithin A. Lower friction to source, a Tier-A evidence outcome catalogued, and broader goal coverage. Reach for Spermidine only if your priority sits squarely in the goals it owns above.
This verdict is generated from each compound's schema (goals, legal status, evidence outcomes, dosing route). It updates automatically as our compound data evolves; the deeper read sits on each individual compound page.
Common questions
What is the difference between Spermidine and Urolithin A?
Spermidine and Urolithin A differ in category (supplement vs supplement), mechanism, and typical dosing. See the side-by-side table for full details.
Which has a longer half-life, Spermidine or Urolithin A?
Spermidine half-life is 6 hours; Urolithin A half-life is 17 hours.
Can you stack Spermidine with Urolithin A?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
Go deeper