Supplement Comparison
Vitamin K2 MK-7 vs MK-4: Which Form Should You Take?
We analyzed what top longevity experts — Huberman, Attia, Patrick, Johnson, and Hyman — actually say about vitamin k2 (mk-7) vs vitamin k2 (mk-4). Here is where they agree and where they don't.
Moderate Consensus
on Vitamin K2 overall
TL;DR — MK-7 for practical daily dosing (longer half-life)
For everyday supplementation, MK-7 is the practical choice: it has a much longer half-life, so a single daily dose keeps blood levels steady, and it's the form in nearly every D3+K2 supplement (100-200mcg). MK-4 clears in hours, so it needs high, multiple daily doses to keep up. The experts who cover K2 — Hyman, Patrick, Johnson — take it as part of a D3+K2 combo (typically MK-7); Attia notably leaves K2 out of his bone-health 'big three' entirely.
What Each Expert Actually Takes
No coverage
Zero vitamin K2 mentions across his analyzed library, despite detailed magnesium/D3/omega-3 coverage.
Omits K2 entirely
Across 5+ bone-health episodes defines the key micronutrients as 'the big three: calcium, D3, and magnesium' — K2 is absent from every discussion, the most notable expert omission in the report.
K2 as a 'longevity vitamin' (form not specified)
Gives the deepest mechanism via Bruce Ames' Triage Theory — K2 supports osteocalcin and matrix GLA protein (bone + arterial calcification). Endorses K2's importance; does not specify MK-4 vs MK-7.
D3K2 daily (combo)
Includes a combined D3K2 supplement in the Blueprint stack; describes D and K2 as the 'workers' that direct calcium to bone rather than arteries.
D3 + K2 (MK-7 combo), always paired
Considers D3+K2 inseparable and one of his top-3 foundational supplements; takes it as a combined D3/K2 product (the MK-7 format) and pairs with magnesium.
Key Differences
Half-life
Vitamin K2 (MK-7)
Long — one daily dose keeps blood levels stable
Vitamin K2 (MK-4)
Short (hours) — needs multiple daily doses or very high amounts
Typical Dose
Vitamin K2 (MK-7)
100-200mcg once daily
Vitamin K2 (MK-4)
Often 1,500mcg+, dosed multiple times a day
Source
Vitamin K2 (MK-7)
Natto (fermented soy) — highest K2 food source
Vitamin K2 (MK-4)
Animal-derived or synthetic
Supplement Availability
Vitamin K2 (MK-7)
The default in almost every D3+K2 product
Vitamin K2 (MK-4)
Less common over the counter
Expert Use
Vitamin K2 (MK-7)
The practical form in the D3+K2 combos Hyman & Johnson take
Vitamin K2 (MK-4)
Not specifically singled out by any expert
Evidence Note
Vitamin K2 (MK-7)
Favoured for practicality + stable levels
Vitamin K2 (MK-4)
Has some Japanese osteoporosis trial data at pharmacologic doses
What the Experts Said (Direct Quotes)
"Vitamin K is prioritized for blood clotting, while its role in preventing arterial calcification and bone fractures is neglected during deficiency, a process exacerbated by drugs like warfarin."
Bruce Ames on Triage Theory, Longevity Vitamins & Micronutrients at 14:15
"Vitamin K1 prioritizes coagulation in the liver, potentially at the expense of preventing arterial calcification. The Triage Theory suggests long-term health functions are sacrificed for short-term survival."
Rhonda Patrick at Orthomolecular Medicine Congress at 05:08
"Minerals like calcium, phosphorus, magnesium, and boron are the concrete, while Vitamin D and K2 are the workers that facilitate calcium absorption and binding."
How Weak Are Your Bones? (Test & Fix) at 01:24
"Supplements including broccoli extract, astaxanthin, ashwagandha, and vitamin D3K2, all aimed at improving health and aging."
My Complete Anti-Aging Diet (ft. Steve Aoki) at 02:37
"Dr. Hyman recommends a core foundation of a high-quality multivitamin, fish oil, and vitamin D3 with K2 for optimal health."
The Ultimate Supplement Guide to Slow Aging (And The 3 to Start With) at 13:06
"Supplementation with D3, ideally with K2 and magnesium, is the most reliable method, with doses tailored to individual needs and levels monitored through testing."
The Truth About Vitamin D & Warning Signs Your Body Is Deficient at 10:07
Bottom Line
Both MK-7 and MK-4 are vitamin K2 — the difference is pharmacokinetics. MK-7 stays in your blood far longer, so 100-200mcg once a day maintains steady levels, and it's what you'll find in essentially every D3+K2 supplement (it's derived from natto). MK-4 is cleared within hours, so the trials that used it relied on high pharmacologic doses taken several times daily — impractical for everyday use. Among our experts, the debate isn't really MK-4 vs MK-7; it's whether to take K2 at all. Hyman treats D3+K2 as inseparable, Patrick calls K2 a 'longevity vitamin' via Triage Theory, and Johnson takes a D3K2 combo daily — all effectively the MK-7 format. The striking omission is Attia, who covers bone health extensively but leaves K2 out of his 'big three,' suggesting he doesn't find the supplementation evidence compelling. If you do supplement, take MK-7 with your vitamin D3 and a fat-containing meal; if you're on a blood thinner, talk to your doctor first.
Consensus Protocol — Vitamin K2
Dosage
100-200mcg MK-7 daily is the commonly cited supplemental dose. No expert specifies an exact K2 dosage in analyzed videos — Hyman and Johnson take it as part of a combined D3/K2 supplement.
Form
MK-7 (menaquinone-7) is the most common supplemental form due to longer half-life. Combined D3/K2 supplements are the most practical format. Food sources include natto (highest K2 content), hard cheeses, egg yolks, and grass-fed butter.
Timing
Take with a fat-containing meal for absorption, same as vitamin D. Morning or midday preferred. Take alongside vitamin D3 for synergistic calcium metabolism.
Notes
Individuals on warfarin or other anticoagulants must consult their physician before supplementing with any form of vitamin K — it can interfere with blood-thinning medication. Vitamin K2 (MK-7) has a longer half-life than K1, meaning consistent daily dosing maintains more stable blood levels. There is no established RDA specifically for K2 — only for total vitamin K (90-120mcg/day).
Now you know which form. Get the full protocol.
Exact dosages — what each expert recommends, not just which form
Daily schedule — morning vs evening, what to pair with food, what to separate
Expert watchdog — get alerted when an expert changes their recommendation
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