Vitamin K2 (Menaquinone)
Best for
Lower fracture risk in older adults
Likely strong benefit · 45 mg/day for 104 weeks · 2 meta-analyses , n=4.5k
27 papers · 6 claims · 61 outcomes scored · 6 positive
Outcomes
What vitamin k2 (menaquinone) actually does, by outcome
Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.
Fewer hip, spine, forearm, and other fractures from weakened bones.
Activates the proteins your body needs for blood clotting and bone building.
Your skeleton tips toward building bone faster than it breaks down.
Keeps mineral packed tightly into hip, spine, and whole-body bone.
Keeps your bone mass intact during the mineral drain of lactation.
Builds thicker walls and a denser internal framework so bones resist fracture.
| Outcome | Effect | Evidence | Dose | Weeks | Rank |
|---|---|---|---|---|---|
| Lower fracture risk in older adults Likely strong benefit | | 2 meta-analyses n=4.5k Meta-analyzed | 45 mg | 104 wk | #1/3 |
| Raise vitamin K levels Likely strong benefit | | 7 meta-analyses n=412 Meta-analyzed | 100–45000 mcg | 2–104 wk | — |
| Strengthen bones by favoring buildup Likely benefit | | 4 meta-analyses n=1.3k Meta-analyzed | 57–1500 mcg | 1–12 wk | #1/5 |
| Build and maintain bone density Promising early signal | | 6 meta-analyses n=623 Meta-analyzed | 45–360 mg | 26–156 wk | #2/9 |
| Protect bones while breastfeeding Promising early signal | | 2 RCTs n=122 | 360 mcg | 26–104 wk | #1/4 |
| Strengthen bone structure Faint early signal | | 1 RCT n=257 | 45 mg | 156 wk | #1/3 |
Recommended Vitamin K2 (Menaquinone) products
Real products that dose Vitamin K2 (Menaquinone) where the research does, in a clean formulation, from brands we've audited. We only list ones we'd stand behind.
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Carlson
Vitamin K2 MK-7 (Menaquinone-7) 180 mcg
Well dosed 180 mcg/day A formulaBrand audit 83/100
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Life Extension
Mega Vitamin K2 45,000 mcg
Well dosed 45,000 mcg/day B formulaBrand audit 90/100
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NutraBio
D3 5000 IU K2 180 mcg
Well dosed 180 mcg/day A formulaBrand audit 90/100
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NOW
MK-7 Vitamin K-2 Extra Strength - 300 mcg
Well dosed 300 mcg/day B formulaBrand audit 87/100
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Protocol For Life Balance
MK-7 Vitamin K2 300 mcg
Well dosed 300 mcg/day B formulaBrand audit 86/100
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Pure Encapsulations
PureHeart K2D
Well dosed 480 mcg/day A formulaBrand audit 78/100
Chosen for adequate Vitamin K2 (Menaquinone) dosing vs. the studied range, a clean formulation (grade A–C), and independent brand-quality audits. Not sponsored.
Sources
- 1. Vitamin K and the prevention of fractures: systematic review and meta-analysis of randomized controlled trials. (2006) ↑
- 2. Vitamin K to prevent fractures in older women: systematic review and economic evaluation. (2009) ↑
- 3. Low-dose menaquinone-4 improves γ-carboxylation of osteocalcin in young males: a non-placebo-controlled dose-response study. (2014) ↑
- 4. The effect of menaquinone-7 supplementation on vascular calcification in patients with diabetes: a randomized, double-blind, placebo-controlled trial. (2019) ↑
- 5. Vitamin K supplementation and arterial calcification in dialysis: results of the double-blind, randomized, placebo-controlled RenaKvit trial. (2021) ↑
- 6. The effect of menaquinone-7 supplementation on dp-ucMGP, PIVKAII, inflammatory markers, and body composition in type 2 diabetes patients: a randomized clinical trial. (2022) ↑
- 7. Vitamin K supplementation impact in dialysis patients: a systematic review and meta-analysis of randomized trials. (2023) ↑
- 8. Vitamin K2 Supplementation in Hospitalised COVID-19 Patients: A Randomised Controlled Trial. (2024) ↑
- 9. Habitual natto intake elevates serum MK-7 levels, enhances osteocalcin carboxylation, and supports bone density: a meta-analysis of Japanese evidence. (2025) ↑
- 10. The Effects of Vitamin K2 on Recovery from Muscle-Damaging Resistance Exercise in Young and Older Adults: The TAKEOVER Randomized Controlled Trial. (2026) ↑
Generated August 14, 2026
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