Comparison
Creatine Monohydrate vs Vitamin D3 + K2
Side-by-side of Creatine Monohydrate 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.
Creatine Monohydrate
Creatine monohydrate supplement guide: 3-5 g/day raises phosphocreatine stores, lifts anaerobic output 5-15%, supports lean mass and cognition under sleep loss.
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
Creatine Monohydrate
- •Increases anaerobic strength and power output by ~5 to 15% across multiple training studies
- •Adds ~1 to 2 kg of lean body mass over 4 to 12 weeks, partly intracellular water and partly true tissue gain
- •Improves 1-rep max on bench and squat by ~5 to 10% versus placebo in resistance-trained adults
- •Cognitive benefit appears mainly under sleep deprivation or high mental load, less so in well-rested individuals
- •Saturation reached in ~28 days at 3 to 5 g/day, or ~5 to 7 days with a 20 g/day loading phase
- •No evidence of renal harm in healthy adults across long-term studies; caution in pre-existing severe renal disease
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 | Creatine Monohydrate | Vitamin D3 + K2 |
|---|---|---|
| Category | supplement | supplement |
| Also known as | creatine | cholecalciferol + menaquinone, D3/K2, vitamin D3 with MK-7 |
| Half-life (hr) ↗ | 3 | 360 |
| Typical dose (mg) ↗ | 5000 | 0.05 |
| Dosing frequency | daily | daily with a fat-containing meal |
| Routes | oral | oral |
| Onset (hr) | 168 | 24 |
| Peak (hr) | - | 168 |
| Molecular weight | 149.15 | 384.64 |
| Molecular formula | C4H9N3O2 | C27H44O (D3); C46H64O2 (MK-7) |
| Mechanism | Donates a phosphate group to ADP via creatine kinase, regenerating ATP during high-intensity, short-duration efforts. | 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 | Dietary supplement (most jurisdictions) | Dietary supplement (global) |
| WADA status | allowed | allowed |
| DEA / Rx | OTC supplement | Not scheduled |
| Pregnancy | Insufficient data | Recommended at standard doses for fetal bone development; consult clinician at higher doses |
| CAS | 57-00-1 | 67-97-0 |
| PubChem CID | 586 | 5280795 |
| Wikidata | Q408389 | Q139347 |
Safety profile
Creatine Monohydrate
Common side effects
- water retention
- mild GI upset at loading doses
- weight gain (2 to 4 lb from intracellular water)
Contraindications
- severe renal impairment
Interactions
- caffeine (high-dose acute): mixed data on ergogenic interference; chronic use appears compatible(minor)
- nephrotoxic drugs (NSAIDs, cyclosporine): theoretical additive renal strain in at-risk patients(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?
Creatine Monohydrate 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 strength or hypertrophy, pick Creatine Monohydrate.
- → If your priority is focus or working memory, pick Creatine Monohydrate.
- → If your priority is bone density, pick Vitamin D3 + K2.
- → If your priority is healthspan extension, pick Vitamin D3 + K2.
Edge case: Half-lives differ materially (Creatine Monohydrate ~3 hr vs Vitamin D3 + K2 ~360 hr). Vitamin D3 + K2 reaches steady state faster; Creatine Monohydrate is easier to dial in if tolerability is uncertain.
Default choice: either is defensible. Creatine Monohydrate 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 Creatine Monohydrate and Vitamin D3 + K2?
Creatine Monohydrate 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, Creatine Monohydrate or Vitamin D3 + K2?
Creatine Monohydrate half-life is 3 hours; Vitamin D3 + K2 half-life is 360 hours.
Can you stack Creatine Monohydrate 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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