Menaquinone-7

A long-chain form of vitamin K2 (MK-7) used in tiny amounts to support vitamin K status, especially for bone and cardiovascular health.

Should I eat Menaquinone-7?

For most adults, MK-7 is a safe, micro-dose form of vitamin K2 with the strongest evidence for supporting bone health. If you take warfarin, involve your clinician and keep your vitamin K intake steady.

Summary

MK-7 comes from bacterial fermentation and is commonly purified by hexane extraction before being standardized into tiny-dose oils or powders. Safety reviews by U.S. and EU authorities support it as a vitamin K source, and a multi-year trial shows benefits on bone-related markers and strength indices. Vitamin K has no established upper intake limit, and long-term MK-7 use in studies has been well tolerated. Cardiovascular benefits are biologically plausible but less certain in clinical outcomes. MK-7 is not appropriate for newborn vitamin K prophylaxis, and U.S. labels may not list menaquinones under “Vitamin K,” so read ingredient lists and coordinate with your care team if you use anticoagulants.

Key Research Points

Can counteract warfarin and similar drugs

All forms of vitamin K, including MK-7, reduce the effect of warfarin; keep your vitamin K intake steady and involve your clinician before making changes.

Highly refined and solvent-extracted

Commercial MK-7 is typically extracted from fermented broth using hexane and then formulated into oils or powders; reputable GRAS dossiers describe controls for residual solvents and purity.

Not for newborn vitamin K prophylaxis

MK-7 is not a substitute for the medically recommended vitamin K1 given to newborns to prevent bleeding; infant dosing should follow medical protocols.

Overview

What is it?

Source: Bacterial fermentation; fermented soy natto

Method: Ferment, extract, refine, and standardize

Processing Level: 8 / 10

Why is it used?

Purpose: Long-acting vitamin K2 used to support activation of bone and vascular proteins.

Commonly found in: supplements; nutrition bars; fortified drinks; dairy; cheese

Why manufacturers choose it: It works at microgram doses without changing taste or macros and is widely accepted as safe.

Origin

MK-7 is the dominant vitamin K form in natto, a sticky fermented soybean food popular in Japan for centuries. Certain bacteria (e.g., Bacillus subtilis used to ferment natto) produce MK-7, which is why aged cheeses and some fermented foods also contain K2. Modern MK-7 ingredients cultivate Bacillus strains in controlled tanks, then extract and standardize MK-7 into microgram-potency oils or powders.

Process: Ferment, extract, refine, and standardize

Steps

1. Ferment: Grow non-pathogenic Bacillus on nutrient media to biosynthesize MK-7.

2. Separate: Dry broth and prepare for solvent extraction.

3. Extract: Use food-grade solvent (e.g., hexane) to isolate MK-7-rich oil.

4. Refine: Concentrate and filter; blend with carriers (e.g., vegetable oil) or emulsifiers.

5. Standardize: Adjust potency to target microgram levels for finished products.

Chemicals

Hexane

Vegetable oil carriers

Glycerol monostearate

Research & Safety

Potential Concerns

The main concern is drug–nutrient interaction: MK-7 can reduce the effect of warfarin and similar anticoagulants; intake should be consistent and medically supervised. Commercial MK-7 is typically made by fermentation and hexane extraction, then blended into an oil or powder; manufacturers report controls on residual solvents and purity in GRAS dossiers. MK-7 is not a substitute for the vitamin K1 dose given to newborns to prevent bleeding. In the U.S., menaquinones are not counted as “Vitamin K” on the Nutrition Facts panel, which can make labels confusing even though the ingredient still affects vitamin K status.

Potential Benefits

MK-7 supports activation (carboxylation) of osteocalcin, a bone protein. In a three-year randomized trial, 180 micrograms per day improved these markers and maintained bone strength indices in postmenopausal women. Vitamin K has an adequate intake level in the EU (about 1 microgram per kilogram body weight daily), and MK-7 can contribute small, steady amounts toward that. Evidence that MK-7 benefits arteries by activating matrix Gla protein is biologically plausible but remains less certain in clinical endpoints.

Digestive Effects

At typical microgram doses, digestive side effects are uncommon. Human studies using 180 micrograms per day for three years reported good overall tolerance with no significant adverse effects. Because doses are tiny and fat-soluble, products are usually formulated in oils or powders to aid delivery, and most people tolerate them well. If you notice stomach upset from a particular product, consider the specific excipients or oils used and discuss alternatives with your clinician.

Limit Consumption

People on warfarin or other vitamin K–antagonist drugs should not change vitamin K intake without clinician guidance; consistency is key. MK-7 is not appropriate for neonatal vitamin K prophylaxis; newborns should receive vitamin K1 per medical protocols. FDA’s GRAS review describes intended uses that can deliver tens of micrograms per day in foods, including for children, within conservative exposure estimates, supporting general safety at these levels. Overall toxicity is considered low, and no upper intake level is established for vitamin K, but individuals with medical conditions affecting clotting should seek personalized advice.

Fact Sheet

Regulatory Status

US FDA: GRAS notice (GRN 887): FDA had no questions for intended use (2020-06-12).

EU Status: EFSA/EC consider menaquinone from Bacillus natto a safe vitamin K source; vitamin K AI set at 1 µg/kg bw/day.

Codex INS: None

JECFA ADI: Not established

ESG & Sustainability

Environmental Footprint: Produced via microbial fermentation; footprint depends on fermentation inputs and solvent recovery—generally low mass per dose.

Sustainability: Fermentation-based production; potential for closed-loop solvent recovery and minimal resource use per microgram dose.

Animal Welfare: No direct animal inputs required for fermentation-derived MK-7.

Carbon Footprint: Very low per serving due to microgram dose; dominated by upstream fermentation energy.

Allergens and Diet

Allergen Status: None

Diet Compatibility: Vegan, Vegetarian, Gluten-free, Dairy-free, Non-GMO

Natural Alternatives

Natto

Source: Fermented soybeans (Bacillus subtilis natto)

Processing Level: Light

Common Uses: Traditional food; small toppings; whole-food K2 source

Replacement Benefit: Whole food source with fiber and additional nutrients.

Why it's not used: Natto’s taste/texture is polarizing and perishable; purified MK-7 is neutral and precise in micrograms.

Aged cheeses

Source: Milk fermented and aged by bacteria

Processing Level: Light

Common Uses: Food topping; snacks

Replacement Benefit: Provides K2 along with protein and calcium as a whole food.

Why it's not used: Cheese adds fat, sodium, allergens; MK-7 adds K2 without altering macros.

Whole-food blends

Source: Powdered natto or K2-rich cheese powders

Processing Level: Moderate

Common Uses: Functional snacks; blends

Replacement Benefit: Less refined than isolated MK-7; contains matrix nutrients.

Why it's not used: Less precise K2 content and stronger flavors; isolated MK-7 offers label control and stability.

Citations

GRAS Notice No. 887 Agency Response Letter (MK-7)

2020-06-12

FDA CFSAN • FDA CFSAN

Commission Decision referencing EFSA opinion on Vitamin K2 sources (Bacillus subtilis natto safe source)

2009-04-22

European Commission • European Commission

Dietary reference values for vitamin K

2017-05-22

EFSA NDA Panel • EFSA Journal

Three-year low-dose menaquinone-7 supplementation...

2013-04-01

Knapen MHJ, Drummen NEA, Smit E, et al. • PubMed

Vitamin K – Health Professional Fact Sheet

2021-03-29

ODS Staff • NIH Office of Dietary Supplements

GRAS Notice No. 245 – Menaquinone-7 (summary page)

2025-09-22

FDA • FDA