Affiliate disclosure: links may earn us a commission at no extra cost to you.
Vitamin K2 (menaquinone-7, or MK-7) is the long-acting, animal-derived form of vitamin K that activates two proteins central to calcium routing in the body: osteocalcin, which directs calcium into bone, and matrix Gla protein, which keeps calcium out of arteries. While vitamin K1 (from leafy greens) primarily supports blood clotting, K2 is increasingly recognized as essential for bone density and cardiovascular health. MK-4 vs MK-7: both are real vitamin K2, but they behave very differently. MK-7 has a long half-life of around 72 hours, so one small daily dose keeps blood levels steady, while MK-4 clears in just a few hours and needs large, multiple daily doses (often 15 mg, several times a day) to match it. For everyday bone and cardiovascular support, MK-7 is the more practical, better-absorbed, and better-studied form, which is why most modern D3+K2 supplements use it. It is especially important to pair K2 with vitamin D3 supplementation. Typical doses are 90-200 mcg of MK-7 per day.
Routes calcium into bones and away from arteries. Critical companion when supplementing high-dose vitamin D3.
Read the full ingredient guide →on blood thinners. Consult a clinician before use.
Take our quiz. We'll compose a complete stack that fits your goals, body, and budget, in minutes.
Take the quiz →