Cross-referencing clinical data
MK-7
- Category
- Vitamin
What MK-7 is, and what it does.
- Time to feel it
- About four weeks of daily use.
How long it takes.
No dosing curve yet.
The dosing trials for MK-7 do not yet agree on a number we would put a line through.
How long it takesPromising
Builds over about four weeks of daily use
A double-blind randomised dose-finding trial gave 60 postmenopausal women aged 50 to 69 either 0, 50, 100 or 200 micrograms of menaquinone-7 daily for four weeks on a controlled diet. The ratio of carboxylated to undercarboxylated osteocalcin rose dose dependently, with significant differences from the 0 microgram group at 100 and 200 micrograms. A companion 12-week trial in 120 people aged 20 to 69 confirmed the change at 100 micrograms daily. Both studies were run by authors affiliated with the R and D division of J-Oil Mills. An independent 8-week double-blind trial in 55 healthy prepubertal children found the same direction at 45 micrograms daily. What was measured is a blood marker of vitamin K status, not bone density and not a sensation.
What the trials show about these together.
Outcomes the engine found studied for these actives as a combination, not one at a time. Each is a finding a named trial measured, cited and dated, never written by the brand.
- PromisingMK-7 + Vitamin DBone
In a meta-analysis of eight randomized trials, vitamin K2 taken together with vitamin D raised total bone mineral density and lowered undercarboxylated osteocalcin, a marker of vitamin K status.
Kuang et al., 2020 (Food & Function)PMID 32219282
Research strength. Research strength says how much work stands behind the combination. It is never a product score.
Fail closed. Where actives were studied on their own rather than together, the record shows each on its own evidence, never a combined effect no trial measured.
Independent record. Every finding is cited to a named trial, dated, and never written by the brand.
Findings from trials that studied these actives as a combination. Context for how the actives were tested together, not a statement about any individual and not a claim about this product.
Plays well withEstablished knowledge, not a trial
No study gave these as a pair, so they are not in the card above. But the reason they belong together is settled biochemistry, not a guess, so it is worth knowing.
MK-7 + Vitamin D3Established sequence of osteocalcin synthesis and carboxylation
Vitamin D drives transcription of osteocalcin in osteoblasts, and vitamin K is the cofactor for the gamma-carboxylation step that lets that protein bind calcium. Supplying one without the other leaves the pathway half finished, which shows up as a higher share of undercarboxylated osteocalcin in circulation. This is why the two are routinely formulated together. The carboxylation ratio is a biochemical marker, not a bone outcome in itself.
MK-7 + CalciumVitamin K dependent proteins are the calcium-binding step
Carboxylated osteocalcin and matrix Gla protein are the proteins that bind calcium in bone matrix and in vessel wall tissue respectively. Menaquinone-7 does not add calcium, it changes how the calcium already present is handled. The pairing is common in bone formulas for that reason.
MK-7 + MagnesiumShared role in bone mineral handling
Magnesium sits in the mineral phase of bone and is involved in the enzymes that handle vitamin D activation. It is a standard third component in bone stacks alongside vitamin D and menaquinone-7. The combination is formulation convention supported by nutrient biology rather than by head-to-head trials of the full stack.
MK-7 + MCT oilMenaquinone-7 is fat soluble
Menaquinone-7 is a lipid, so it needs dietary fat and bile to form the micelles that carry it across the intestinal wall. Oil suspensions and softgels exist for exactly this reason. Taking a dry powder form on an empty stomach gives a lower and more variable absorption than taking it with a fat-containing meal.
MK-7 + Fish oilFat vehicle plus common co-formulation
An omega-3 softgel provides the lipid phase that a fat-soluble vitamin needs, which is why menaquinone-7 is often dissolved directly into one. The pairing is about delivery rather than any shared biological target. Oxidation of the oil is the practical thing to watch, since a rancid carrier is a problem for the vitamin sitting in it.
MK-7 + Vitamin K1Different vitamers of the same cofactor with different pharmacokinetics
Phylloquinone and menaquinone-7 both feed the same gamma-carboxylation reaction, but they behave differently in the body: phylloquinone clears quickly and is taken up strongly by the liver, while menaquinone-7 has a longer circulating half-life and reaches extrahepatic tissue in greater proportion. Neither is the correct choice in general. Phylloquinone tracks the green-vegetable end of dietary intake, menaquinone-7 the fermented-food end.
MK-7 + ProbioticsBacterial synthesis of long-chain menaquinones
Several gut bacteria synthesise menaquinones of varying chain length, and Bacillus subtilis natto is the organism behind commercial MK-7 production. How much of that bacterially made vitamin K a person actually absorbs from the colon is still contested. Read the pairing as plausible rather than quantified.
MK-7 + Vitamin EReported interference of high-dose tocopherol with vitamin K status
High doses of alpha-tocopherol have been reported to lower vitamin K dependent carboxylation, probably through effects on vitamin K metabolism and clearance. The effect is not seen at ordinary dietary intakes. Anyone stacking a high-dose vitamin E product with menaquinone-7 should know the two are not fully independent.
MK-7 + Collagen peptidesMatrix protein plus the carboxylation cofactor
Bone is a collagen scaffold that is then mineralised, and osteocalcin is one of the non-collagen proteins that binds calcium into that scaffold. Combining a collagen supply with the cofactor for the mineral-binding step is a coherent formulation idea. There is no trial of the combination, so this is reasoning from structure, not from measured results.
Who should be cautious
Nothing specific on file for MK-7. Match the label to the daily amount above, and tell your doctor what you take.
Not medical advice. Show the label to your pharmacist.What the strongest studies found
The essence, in one line each.
- Habitual natto intake was associated with higher serum MK-7, greater osteocalcin carboxylation and higher measured bone density.Cohort study. Wen Z et al., 2025 (Frontiers in Nutrition). PMID 41393956 ↗
- Pooled trials of MK-7 supplementation examined body measurements, blood sugar indices and blood lipids, with effects that were small and inconsistent across studies.Meta-analysis. Nikpayam O et al., 2025 (Prostaglandins Other Lipid Mediat). PMID 40054729 ↗
- Reported that effects of MK-7 supplementation on body composition and adiposity markers differed between men and women.Randomised trial. Bittner R et al., 2026 (Nutrients). PMID 42280344 ↗
- No coagulation activation was detected after MK-7 supplementation in the population studied.Randomised trial. Bladbjerg EM et al., 2024 (J Ren Nutr). PMID 38128853 ↗
- No difference was detected between low and high MK-7 doses on bone structure and remodelling measures in the model used.Animal study. Chiang HJ et al., 2026 (Nutrients). PMID 42197064 ↗
- Examined vitamin K2 supplementation and recovery markers after muscle-damaging resistance exercise in younger and older adults.Randomised trial. Lithgow H et al., 2026 (Med Sci Sports Exerc). PMID 41843412 ↗
- Described longitudinal height growth patterns in children receiving menaquinone-7 supplementation.Cohort study. Nguyen ND et al., 2026 (Nutrients). PMID 42356365 ↗
These are the studies our verdict leans on, chosen from the 7 we read for MK-7. The full linked list is below.
The studies, linked.
8 sources behind our MK-7 verdict: peer-reviewed studies and registered clinical trials. Every one links straight to PubMed, the journal, or ClinicalTrials.gov. Read them yourself.
- Clinical trialPilot Study of Vitamin K2 (MK-7) and Vitamin D3 Supplementation and the Effects on PASC Symptomatology and Inflammatory BiomarkersClinicalTrials.gov ↗NA · 151 participants · Completed
- Clinical trialSafety and Efficacy of Vitamin K Antagonists Versus Rivaroxaban in Hemodialysis Patients With Atrial Fibrillation: a Multicenter Randomized Controlled TrialClinicalTrials.gov ↗PHASE4 · 132 participants · Completed
- Clinical trialComparative Study of Three Delivery Systems of Menaquinone-7ClinicalTrials.gov ↗NA · 107 participants · Completed
- Clinical trialFood Supplementation With Vitamin K2 to Activate MGP as an Endogenous Inhibitor of Vascular Calcification in Hemodialysis PatientsClinicalTrials.gov ↗PHASE3 · 53 participants · Completed
- ClinicalTrials.gov ↗
- Clinical trialIntervention Study on the Effect of Vitamin K2 (Menaquinone-7) Supplementation on the Vascular Stiffness in Subjects With Poor Vitamin K-statusClinicalTrials.gov ↗NA · 240 participants · Unknown
- Clinical trialOral Vitamin K2 (Menaquinone-7; MK-7) Supplementation and Effect on Vitamin K Status of Breastfed Term Infants in Early Infancy; a Four-cohort Prospective, Part-randomised, Part-blinded Study.ClinicalTrials.gov ↗NA · 134 participants · Not yet recruiting
- Clinical trialEffects of Vitamin K2 and D3 Supplementation on 18F-NaF PET/MRI in Patients With Carotid and Coronary Artery DiseaseClinicalTrials.gov ↗NA · 52 participants · Unknown
Evidence surfaced via Semantic Scholar (Allen Institute for AI) and ClinicalTrials.gov. Ranked by study type and citation weight, not cherry-picked.
Problems people have reported.
Read this carefully. These are 253 voluntary, unverified reactions reported to the FDA (openFDA). The number mostly reflects how popular MK-7 is, not how risky it is. A report is not proof MK-7 caused anything. It is a signal of what to watch for, nothing more.
Fatigue
11
Nausea
10
Pain
9
Arthralgia
7
Feeling Abnormal
7
Asthenia
6
Source: openFDA adverse-event reports. Voluntary reporting, not an incidence rate.
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. This information is for educational purposes only and is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement regimen.
