Vitamin K1 vs Vitamin K2 MK-4
How vitamin K1 and vitamin K2 MK-4 differ in potency, absorption, tolerance, and cost.
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Side by Side
| Vitamin K1 (Phylloquinone) | Vitamin K2 as MK-4 (Menatetrenone) | |
|---|---|---|
| Absorption | Moderate | Low |
| How it is absorbed | Fat-soluble, absorbed with dietary fat. Taken up mainly by the liver for clotting factor carboxylation; short plasma half-life of a few hours. | Short-chain menaquinone with a half-life of hours. A 420 mcg oral dose was not detectable in serum in Sato 2012, so it requires milligram doses taken several times daily. |
| Typical dose | 90-120 mcg daily (AI for total vitamin K) | 45 mg daily in divided doses (Japanese osteoporosis regimen) |
| Common uses | dietary vitamin K, warfarin reversal (prescription), newborn prophylaxis | osteoporosis (approved drug in Japan) |
| Side effects | Antagonizes warfarin; intake must be kept consistent. | Interacts with warfarin. |
| Cost | Low | Moderate |
| Also called | phylloquinone, phytonadione | menatetrenone, MK-4 |
| Labels in index | 19 | 97 |
When to Choose Vitamin K1 (Phylloquinone)
Choose vitamin K1 when the goal is meeting vitamin K needs for clotting. Listed here as the reference form for comparison with K2. Leafy greens are the main dietary source.
Vitamin K1 (Phylloquinone)
Choose vitamin K1 when the goal is meeting vitamin K needs for clotting.
What to look for: Vitamin K1 named on the Supplement Facts panel, with the amount per serving stated.
Find on iHerb Affiliate linkWhen to Choose Vitamin K2 as MK-4 (Menatetrenone)
Choose vitamin K2 MK-4 when a clinician uses the high-dose Japanese osteoporosis protocol. The body also converts K1 to MK-4 in tissues.
Vitamin K2 as MK-4 (Menatetrenone)
At microgram doses it barely registers in serum. At the 45 mg Japanese dose it is a drug, not a supplement.
What to look for: Skip low-dose MK-4 products. The milligram regimen belongs under medical supervision.
Find on iHerb Affiliate linkProducts on Titrate
In Titrate's index of NIH label data, 19 labels named as vitamin K2 products list vitamin K1 and 97 list vitamin K2 MK-4.
Vitamin K2 does not have its own search category yet. Each product above links to its full label in the NIH database.
Related
References
NIH Office of Dietary Supplements. Vitamin K: Fact Sheet for Health Professionals.
Geleijnse JM, et al. Dietary intake of menaquinone is associated with a reduced risk of coronary heart disease: the Rotterdam Study. J Nutr. 2004;134(11):3100-3105.
Cockayne S, et al. Vitamin K and the prevention of fractures: systematic review and meta-analysis of randomized controlled trials. Arch Intern Med. 2006;166(12):1256-1261.
Schurgers LJ, et al. Vitamin K-containing dietary supplements: comparison of synthetic vitamin K1 and natto-derived menaquinone-7. Blood. 2007;109(8):3279-3283.
Sato T, et al. Comparison of menaquinone-4 and menaquinone-7 bioavailability in healthy women. Nutr J. 2012;11:93.
Theuwissen E, et al. Effect of low-dose supplements of menaquinone-7 (vitamin K2) on the stability of oral anticoagulant treatment: dose-response relationship in healthy volunteers. J Thromb Haemost. 2013;11(6):1085-1092.
Knapen MH, et al. Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women. Osteoporos Int. 2013;24(9):2499-2507.
Diederichsen ACP, et al. Vitamin K2 and D in Patients With Aortic Valve Calcification: A Randomized Double-Blinded Clinical Trial. Circulation. 2022;145(18):1387-1397.