Vitamin K2 dosage and evidence
Written by Aaron CuhaReviewed Sep 2026
The short answer
The K2 half of the owner's D3 plus K2 floor pairing. Observational menaquinone intake tracked with less coronary heart disease in Rotterdam. A three-year MK-7 trial reported less bone loss in healthy postmenopausal women. Warfarin is a hard stop.
- People given it
- 0
- Human studies
- 0
- Found nothing
- 0
Dose
No human dose established
No published study on this page has given this compound to people and reported a result.
2 human studies where nobody was given it
No first-hand reports gathered yet. That is a gap in what we have collected, not a finding that nothing has been reported.
What it has been measured to do
Measured in people
Goals Vitamin K2 has been measured for in a human being, most people first. Counts come from the study lines on this page and deliberately undercount.
- Bone strengthno headcount stated · 1 study
35 of the 36 indexed goals have no study of any kind behind Vitamin K2
No trial, no animal work, no cell work on this page reports a result for these. That is an absence of evidence rather than evidence of absence, but it does mean anything you have been told about Vitamin K2 and one of these did not come from a study cited here.
When this earns a spot
It sits on the owner's floor next to D3 as MK-7, not as a stand-alone longevity drug. The Rotterdam cohort associated higher dietary menaquinone with less coronary heart disease. That is observational. A three-year MK-7 trial in healthy postmenopausal women reported less bone loss. Warfarin or any vitamin-K antagonist is a hard clinician gate. Do not start K2 on those medicines from a page.
Owner stack tier 1
Bloodwork that belongs beside the bottle
Read K2 beside 25-OH D and the medicine list, not as its own stack.
Default retest window: 90 days. If the named marker did not move, stop.
- There is no routine consumer 'K2 blood test' this site will tell you to chase.
- INR belongs to the clinician if you are anticoagulated, and K2 does not.
Reading the number
If you are on warfarin, this bottle is not yours to add. If you are not, K2 is a pairing choice with D3. Coronary calcium talk is a clinician imaging conversation, not a K2 protocol.
Marker glossary: 25-hydroxy vitamin D.
What people typically order
Ask the clinician who owns your vitamin D whether K2 is compatible with your medicines. Do not order an INR-to-self kit to justify a capsule.
Show full evidence
Overview
Vitamin K2 is a family of menaquinones, most often sold as MK-7. The owner takes it beside vitamin D3. That pairing is a stack choice, not a trial that randomised D3 plus K2 against D3 alone for deaths or fractures in a general longevity audience.
The Rotterdam Study associated higher dietary menaquinone with a lower risk of coronary heart disease. That is food-frequency observation, not a capsule trial. A three-year randomised MK-7 study in healthy postmenopausal women reported reduced bone loss. It is one of the cleaner human files this stub can honestly cite.
The hard limit is anticoagulation. Anyone on warfarin or another vitamin-K antagonist does not add K2 from a webpage. There is no consumer K2 blood test this site will tell you to chase. Read it beside 25-OH D and the medicine list.
Mechanism of action
Vitamin K is a cofactor for gamma-carboxylation of vitamin-K-dependent proteins, including clotting factors and osteocalcin. MK-7 is a long-chain menaquinone with a longer circulating half-life than MK-4. Carboxylation of osteocalcin and matrix Gla protein is the mechanistic basis of the bone and calcification claims. Mechanism is not an outcome.
Human evidence
One useful randomised bone-density file for MK-7, plus a large dietary observation on menaquinone and coronary disease. No outcome trial of a D3 plus K2 capsule for death or heart attacks sits on this stub.
- Rotterdam associated dietary menaquinone, not a supplement aisle MK-7, with less coronary heart disease.
- A three-year MK-7 trial in healthy postmenopausal women reported less bone loss.
- Nobody on this page was randomised to D3 plus K2 versus D3 alone for mortality.
What this does not tell you: This is not a license to start K2 on warfarin. Observational diet is not a capsule. Bone density is not fracture. A later pass should write the calcification-imaging file properly or say it cannot.
The evidence, charted
Fig. 1a · evidence scale
2human studies cited, participant count not stated
participants not stated
No participant total is drawn, because none of the human citations on this page gives one. Read the citations below for what each study measured.
Participant counts are read from the citation lines on this page. Where a line states no number, nothing is counted for it rather than estimated.
Fig. 1b · evidence mix
All 2 citations here are human work.
- Human · given to people2100%
Counted from the citation list on this page, typed as this page types it. It understates any literature larger than the sources we cite, and a review counts once however many studies it covers.
Fig. 2 · evidence over time
Citations here span just two years, 2004 and 2013.
Too few distinct publication years on this page to plot as a timeline. The newest citation on file is from 2013, more than five years ago; the published record may have gone quiet.
Fig. 3 · legal status at a glance
US
Not approved
UK
Not approved
AU
Not approved
CA
Not approved
Not approved in any of the four jurisdictions shown. A jurisdiction's classification is a regulatory fact, not a verdict on the science; see Legal status below for the full text and any notes.
Fig. 4 · dose response
No human dose response curve exists
We draw this figure where the data supports it. For this compound in humans it does not, so the panel stays empty rather than borrowing an animal curve and implying it transfers.
Fig. 5 · molecular identity
- Modality
- Supplement
- Molecular weight
- MK-7 about 649 Da. A fat-soluble vitamin, not a peptide.
- Half-life
- None on file
- Sequence length
- None on file
No amino acid sequence is on file for Vitamin K2, which is expected: a supplement is not built from residues.
Key studies & citations
- Human2004Dietary intake of menaquinone is associated with a reduced risk of coronary heart disease: the Rotterdam Study.
Observational. Higher dietary menaquinone associated with less coronary heart disease and aortic calcification. Not a capsule trial and not phylloquinone (K1) showing the same pattern.
- Human2013Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women.
Randomised MK-7 for three years in healthy postmenopausal women. Reported attenuated bone loss. Not a fracture-outcome trial and not a general-population longevity trial.
Frequently asked questions
Has Vitamin K2 been tested in people?
The K2 half of the owner's D3 plus K2 floor pairing. Observational menaquinone intake tracked with less coronary heart disease in Rotterdam. A three-year MK-7 trial reported less bone loss in healthy postmenopausal women. Warfarin is a hard stop. 2 human studies where nobody was given it. 0 people given it across 0 completed trials. 0 found nothing.
What is the Vitamin K2 dosage?
No human dose established. No published study on this page has given this compound to people and reported a result. 2 human studies where nobody was given it
Is Vitamin K2 FDA-approved?
Sold as a dietary supplement in the United States. Not approved to prevent heart disease or fractures. Warfarin remains a prescription anticoagulant that K2 can disturb.
Do I take K2 because I take vitamin D?
The owner does. That is a pairing, not a trial mandate. The reason to pause is medicines that depend on vitamin K, not a missing blood test.
Is this a blood-marker supplement?
Not by itself. Read 25-OH D. There is no routine consumer K2 assay this site treats as a start/stop gate.