About Vitamin K
K1 (phylloquinone) primarily supports blood clotting, while K2 (menaquinones) directs calcium into bones and teeth rather than arteries. Among K2 forms, MK-7 has a much longer half-life (~96 hours vs 1–8 hours for MK-4), making it far more effective for bone density and cardiovascular health at lower doses. MK-7 is the preferred supplemental form for long-term calcium metabolism support.
What Vitamin K supports
- Strengthens bone density
- Enables proper blood clotting
How much Vitamin K to take
Clinical studies typically use 90–200 mcg of Vitamin K. MK-7 supplements typically provide 100–200 mcg.
- RDA
- 120 mcg
- Effective range
- 90–200 mcg
Forms of Vitamin K compared
- Menaquinone-7 (MK-7)PremiumLong half-life (~3 days). Active in bone and arterial tissue.
- Menaquinone-4 (MK-4)StandardShort half-life; requires multi-daily dosing for full effect.
- Phytonadione (K1)BudgetSynthetic K1; short half-life and weak bone/arterial activity vs MK-7.
Clinical evidence
Strong clinical evidence. MK-7 form confirmed in multiple trials for bone density; K1 essential for blood clotting via coagulation cascade
NIH Fact Sheet