Comparison
Urolithin A vs Vitamin D3 + K2
Side-by-side of Urolithin A and Vitamin D3 + K2. 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.
Urolithin A
Urolithin A supplement guide: pomegranate-derived metabolite, 500-1000 mg Mitopure dosing, mitophagy and muscle endurance evidence.
Vitamin D3 + K2
Vitamin D3 K2 supplement profile: cholecalciferol at 1000-4000 IU/day corrects deficiency, MK-7 directs calcium to bone, away from arteries.
Effects at a glance
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
Vitamin D3 + K2
- •Reduces non-vertebral fractures 10-20% in older adults at 800 IU/day or above when combined with calcium
- •VITAL trial showed neutral results on primary CV and cancer endpoints at 2000 IU/day over 5 years
- •Vitamin D supplementation reduces respiratory infection incidence ~10-20% in deficient populations
- •K2 MK-7 has 72-hour plasma half-life vs 1-2 hours for MK-4; once-daily dosing is sufficient
- •Synergy hypothesis is largely preclinical; dedicated combination RCTs are limited
- •Daily dosing outperforms bolus dosing for immune and infection outcomes
Side-by-side
| Attribute | Urolithin A | Vitamin D3 + K2 |
|---|---|---|
| Category | supplement | supplement |
| Also known as | UA, Mitopure, ellagitannin metabolite | cholecalciferol + menaquinone, D3/K2, vitamin D3 with MK-7 |
| Half-life (hr) ↗ | 17 | 360 |
| Typical dose (mg) ↗ | 500 | 0.05 |
| Dosing frequency | daily, morning with food | daily with a fat-containing meal |
| Routes | oral | oral |
| Onset (hr) | 2 | 24 |
| Peak (hr) | 4 | 168 |
| Molecular weight | 228.2 | 384.64 |
| Molecular formula | C13H8O4 | C27H44O (D3); C46H64O2 (MK-7) |
| Mechanism | Induces mitophagy via potentiation of PINK1/Parkin signaling, leading to selective degradation of damaged mitochondria. Secondary anti-inflammatory effects via NF-kB modulation. | D3 converts to calcidiol then calcitriol, activating the vitamin D receptor (VDR) to increase intestinal calcium absorption and modulate immune and bone gene transcription. K2 carboxylates osteocalcin and matrix Gla protein, directing calcium toward bone and inhibiting vascular calcification. |
| Legal status | OTC dietary supplement (US GRAS 2018; EFSA Novel Food 2021) | Dietary supplement (global) |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement (not scheduled) | Not scheduled |
| Pregnancy | Insufficient data; not routinely recommended | Recommended at standard doses for fetal bone development; consult clinician at higher doses |
| CAS | 1143-70-0 | 67-97-0 |
| PubChem CID | 5488186 | 5280795 |
| Wikidata | Q27101321 | Q139347 |
Safety profile
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)
Vitamin D3 + K2
Common side effects
- GI upset at high doses
- headache (rare)
- hypercalcemia (only at sustained very high D3 doses)
Contraindications
- hypercalcemia
- sarcoidosis
- active hyperparathyroidism
- warfarin therapy (K2 component requires stable intake)
Interactions
- warfarin: K2 component can affect anticoagulation; maintain stable intake and inform anticoagulation clinic(moderate)
- thiazide diuretics: additive calcium retention; hypercalcemia risk with high-dose D3(moderate)
- digoxin and calcium channel blockers: additive effects from D3-induced hypercalcemia(moderate)
- glucocorticoids: reduced vitamin D efficacy and bone effects(moderate)
- cholestyramine and orlistat: bind fat-soluble vitamins; separate dosing by 2 to 4 hours(moderate)
Which Should You Take?
Urolithin A and Vitamin D3 + K2 score evenly on the criteria we weight (goal breadth, legal accessibility, evidence depth). The conditionals below should drive the decision more than any aggregate score.
- → If your priority is muscle hypertrophy, pick Urolithin A.
- → If your priority is mitochondrial function, pick Urolithin A.
- → If your priority is bone density, pick Vitamin D3 + K2.
- → If your priority is cardiovascular health, pick Vitamin D3 + K2.
Edge case: Half-lives differ materially (Urolithin A ~17 hr vs Vitamin D3 + K2 ~360 hr). Vitamin D3 + K2 reaches steady state faster; Urolithin A is easier to dial in if tolerability is uncertain.
Default choice: either is defensible. Urolithin A edges out on goal breadth + legal accessibility; Vitamin D3 + K2 is the right call if your priority sits in the goals listed 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 Urolithin A and Vitamin D3 + K2?
Urolithin A and Vitamin D3 + K2 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, Urolithin A or Vitamin D3 + K2?
Urolithin A half-life is 17 hours; Vitamin D3 + K2 half-life is 360 hours.
Can you stack Urolithin A with Vitamin D3 + K2?
Stack compatibility depends on mechanism overlap, legal status, and individual response. Check each compound page for specific interactions and contraindications before combining.
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