If you’ve wandered into the MK-4 vs MK-7 debate, you’ve probably seen passionate opinions and confusing dosing. Here’s the short version from Dr. Brown’s clip: MK-4 is a form of K2 with a short half-life that generally requires milligram-level dosing, while MK-7 is a naturally fermented K2 with a long half-life effective at microgram-level doses. Translation: MK-7 stays active longer and is easier to take once daily.
Vitamin K, Quickly: K1 vs K2 (MK-4 vs MK-7)
- Vitamin K1: abundant in leafy greens; mainly supports normal blood clotting.
- Vitamin K2: activates proteins that put calcium into bones and keep it out of arteries.
- MK-4: short-acting K2 subtype; often used in mg amounts multiple times per day.
- MK-7: long-acting K2 subtype from fermentation; effective in mcg amounts, typically once daily.
From the video: “MK7…has a long half-life. So you only have to use micrograms as compared to milligrams. The research…most effective is on MK7…and that is what’s been clearly documented to build bone and protect from arterial calcification.”
Why Many Clinicians Favor MK-7
Consistency matters. MK-7’s longer half-life maintains steadier blood levels, supporting continuous activation of bone-building (osteocalcin) and artery-protective (matrix-GLA) proteins. Multiple clinical trials link daily MK-7 with improved bone markers and healthier arterial flexibility.
How to Use Vitamin K2 Wisely
- If you want ease + once-daily dosing, MK-7 is the practical pick.
- Consumer-friendly intake commonly falls around 90–200 mcg/day for MK-7 (check with your clinician).
- Dr. Brown prefers 180 mcg for bone health.
- Pair K2 with Vitamin D3: D helps absorb calcium; K2 helps direct it into bones (and away from soft tissues).
- Don’t forget the basics: magnesium, protein, and weight-bearing exercise also build bone.
Safety Notes
- If you’re on warfarin or other vitamin-K–interacting anticoagulants, consult your prescriber before taking K2.
- For most healthy adults, typical supplemental intakes are well tolerated.
Frequently Asked Questions
Do I need both Vitamin D and K2?
Vitamin D helps you absorb calcium; Vitamin K2 helps use that calcium correctly by activating proteins that put it into bones and keep it out of arteries. They work best together.
Is MK-7 the only effective form?
Both MK-4 and MK-7 are forms of K2. MK-7’s longer half-life makes it easier to take once daily in microgram amounts, which is why most modern research and consumer products focus on MK-7.
