Blood sugar and insulin
Vitamin K2 (menaquinone-7)and HOMA-IR
Two sources here, and they say different things: one measured lower HOMA-IR and one found no clear difference.
How sure anyone can be
Low certainty, level 2 of 4Further research is likely to change this.
The most certain of the two findings here; each record carries its own.
The numbers reported
One source’s range, drawn against its own line of no difference and scaled to its own numbers.
-0.76-0.56 standardised effect size-0.35
This range stays on one side of the no-difference line.
Two sources, newest first
We do not pick between these or average them into one number.
What we read is the published abstract, not the full paper, so a blank below may still be printed in the paper itself. A fixed rule worked this out from the source’s own fields. Nobody checked this rating by hand.
Systematic review, 2025 · 6 studies pooled
Very low certainty, level 1 of 4Effect of Menaquinone-7 (MK-7) Supplementation on Anthropometric Measurements, Glycemic Indices, and Lipid Profiles: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Prostaglandins Other Lipid Mediat. 2025;177:106970. doi:10.1016/j.prostaglandins.2025.106970. PMID:40054729.
- Number reported
- -0.56 standardised effect size
- Which way it went
- Lower
- Likely range
- -0.76 to -0.35
- Source’s own words
- standardised mean difference in HOMA-IR vs control
- Who was studied
- Adult
- Compared with
- control
- Amount taken
- Recorded detail — MK-7 (the abstract's subgroup cut-off is printed as 90 mg/d)
- For how long
- Not in the abstract
- Disagreement between studies
- I2 = 84.3%
- Kind of record
- Journal article
How this rating was reachedstarts at High, 3 steps down: risk of bias, imprecision and inconsistency
- Starts at High
- Risk of bias brought it down to Moderatethe abstract reports no risk-of-bias or quality appraisal, so study limitations cannot be ruled outNot in the abstract
- Imprecision brought it down to Lowthe abstract does not state how many participants were pooledNot in the abstract
- Inconsistency brought it down to Very lowheterogeneity across pooled studies is high (I² = 84.3%)Reported in the abstract
- Ends at Very low3 steps down.
- Checked, nothing to step it down for
- indirectness
Imprecision stops at the first check that applies; others may apply too.
AI review could not confirm it — an AI agent re-read this finding against the saved source and at least one check failed. The batch record names the check and quotes the sentence that caused the doubt. No person read it.
Randomised trial, 2021
Low certainty, level 2 of 4Vitamin K2 (menaquinone-7) increases plasma adiponectin but does not affect insulin sensitivity in postmenopausal women: a randomized controlled trial.
Eur J Clin Nutr. 2021;75(11):1661-1667. doi:10.1038/s41430-021-00884-8. PMID:33664429.
- Number reported
- Not in the abstract
- Which way it went
- No clear difference
- Likely range
- Not in the abstract
- Source’s own words
- no HOMA-IR point estimate is reported in the abstract
- Who was studied
- Postmenopausal women
- Compared with
- placebo, with both arms on calcium 800 mg and vitamin D 38 microg
- Amount taken
- 375 microg/d MK-7
- For how long
- 365 days
- Disagreement between studies
- Not in the abstract
- Kind of record
- Journal article
How this rating was reachedstarts at High, 2 steps down: risk of bias and imprecision
- Starts at High
- Risk of bias brought it down to Moderatethe abstract reports no risk-of-bias or quality appraisal, so study limitations cannot be ruled outNot in the abstract
- Imprecision brought it down to Lowthe abstract reports no confidence interval for the estimateNot in the abstract
- Ends at Low2 steps down.
- Checked, nothing to step it down for
- indirectness
- Inconsistency
- One study, so there was nothing to disagree
Imprecision stops at the first check that applies; others may apply too.
AI-reviewed & signed — an AI agent re-read this finding against the saved source and checked that the quote, the numbers, the units and the direction match it. No person read it. The owner authorised the agent to sign the batch with the owner's key, and every build rechecks that signature against these exact bytes.
What is still missing from these readings
- One give no number at all, only which way it went.
- One gives no likely range, so how precise that number is is unknown.
- Two do not say how many people took part.
- For how long — One of Two readings: Not in the abstract.
Something nobody wrote down is never a zero and never a guess.
Still to read for Vitamin K2 (menaquinone-7)
One of the nine things on our list for Vitamin K2 (menaquinone-7) has no reading here yet:
- Serum menaquinone-7 (MK-7)
Still to read means nobody here has got to it, not that it was tried and did nothing or that no research exists. A pairing on no list is not a gap: we never set out to read it.
Read next
Vitamin K2 (menaquinone-7)
Seven other questions read for it
Blood sugar and insulin
45 questions read under it
HOMA-IR
Eight other ingredients read against it
First six, alphabetical, and by nothing else. The rest are on Blood sugar and insulin.
This is a library, not advice. No recommendation, no dose, no diagnosis, no ranking. We never ask about your symptoms, and nothing here is tailored to you.