Home Ingredients VitaMK7® (Vitamin K2 as MK-7 — Gnosis)
Bone Health

VitaMK7® (Vitamin K2 as MK-7 — Gnosis)

Evidence Level
Moderate
1 Clinical Trial
3 Documented Benefits
3/5 Evidence Score

VitaMK7® is a natural vitamin K2 in the menaquinone-7 (MK-7) form from Gnosis, produced by fermentation of Bacillus subtilis natto and standardized to over 99% of the active all-trans isomer. Vitamin K2 is required to activate osteocalcin, the protein that binds calcium into the bone matrix. The strongest human evidence for MK-7 is a 3-year randomized trial in postmenopausal women showing slower age-related bone loss. The related idea that MK-7 keeps calcium out of artery walls (via matrix Gla protein) is a proposed mechanism and is not demonstrated by the trial cited on this page.

Studied Dose Commonly 90 to 180 mcg of MK-7 per day. The 3-year bone trial cited on this page used 180 mcg/day. Published trials test MK-7 as a form; no trial of the VitaMK7® brand itself is cited here.
Active Compound Vitamin K2 as menaquinone-7 (MK-7), greater than 99% all-trans isomer, from natto fermentation.

Benefits

Bone strength

In a 3-year randomized trial in 244 healthy postmenopausal women, 180 mcg/day of MK-7 improved vitamin K status and decreased the age-related decline in bone mineral content and bone mineral density at the lumbar spine and femoral neck compared with placebo (Knapen 2013). This is the best-supported use of MK-7 and the evidence is specific to bone.

Supported by Trial 1

Vascular calcium handling — mechanism only

Vitamin K2 is a cofactor for the carboxylation (activation) of matrix Gla protein, which in laboratory and animal work binds calcium in vessel walls. This is a mechanism, not an outcome: the 3-year human trial cited on this page measured bone density and vitamin K status, not arterial stiffness or vascular calcification, so no cardiovascular benefit is demonstrated by the evidence presented here.

Supported by Trial 1

Calcium routing

MK-7 supports the carboxylation of vitamin-K-dependent proteins involved in calcium handling, including osteocalcin in bone, and is commonly paired with calcium and vitamin D. The broader idea that MK-7 "routes" dietary calcium into bone and away from soft tissue is a mechanistic hypothesis rather than an outcome measured in the trial cited here.

Supported by Trial 1

Mechanism of action

1

Osteocalcin activation

MK-7 carboxylates (activates) osteocalcin, the protein that binds calcium into the bone matrix, strengthening bone.

2

Matrix Gla protein activation

MK-7 carboxylates (activates) matrix Gla protein, which in laboratory and animal work inhibits calcium deposition in artery walls. This is a proposed mechanism only — the human trial cited on this page measured bone outcomes, not arterial calcification, stiffness, or cardiovascular events.

Clinical trials

1
MK-7 and Bone Loss — 3-Year RCT
PubMed

Three-year randomized, placebo-controlled trial of 180 mcg/day menaquinone-7 (MK-7) in 244 healthy postmenopausal women. (Knapen et al. 2013, Osteoporosis International). Endpoints were vitamin K status and bone density; the trial tested MK-7 as a nutrient form, and no trial of the VitaMK7® brand itself is cited on this page.

Healthy postmenopausal women.

MK-7 at 180 mcg/day for 3 years significantly improved vitamin K status and decreased the age-related decline in bone mineral content and bone mineral density at the lumbar spine and femoral neck versus placebo. Bone and vitamin K status were the endpoints measured; the trial did not assess arterial stiffness, vascular calcification, or cardiovascular events.

Side effects and drug interactions

Common Potential side effects

Generally well-tolerated at recommended doses.
Vitamin K2 interferes with warfarin-type blood thinners; do not use without medical supervision.
Mild digestive upset is occasionally reported.

Important Drug interactions

Warfarin / vitamin-K-antagonists — directly opposes these blood thinners; medical supervision required.
Beyond vitamin K antagonists, no other significant drug interactions are well documented — but this is an absence of published data, not a guarantee of safety.
Tell your doctor if you take anticoagulants.

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Frequently asked questions about VitaMK7® (Vitamin K2 as MK-7 — Gnosis)

What is VitaMK7?

VitaMK7® is a natural vitamin K2 in the menaquinone-7 (MK-7) form from Gnosis, produced by fermentation of Bacillus subtilis natto and standardized to over 99% of the active all-trans isomer. Vitamin K2 is required to activate osteocalcin, the protein that binds calcium into the bone matrix.

What is VitaMK7 used for?

VitaMK7 is researched primarily for Bone Health. In a 3-year randomized trial in 244 healthy postmenopausal women, 180 mcg/day of MK-7 improved vitamin K status and decreased the age-related decline in bone mineral content and bone mineral density at the lumbar spine and femoral neck comp…

What is the recommended dosage of VitaMK7?

The clinically studied dose is Commonly 90 to 180 mcg of MK-7 per day. The 3-year bone trial cited on this page used 180 mcg/day. Published trials test MK-7 as a form; no trial of the VitaMK7® brand itself is cited here. Always follow the product label and check with a healthcare provider for personal advice.

Is VitaMK7 safe, and does it have side effects?

For most healthy adults, VitaMK7 is well tolerated at studied doses. Reported effects can include: Generally well-tolerated at recommended doses. Vitamin K2 interferes with warfarin-type blood thinners; do not use without medical supervision. It may also interact with some medications. VitaMK7 is not right for everyone, so check with a healthcare provider first if you are pregnant or breastfeeding, have a medical condition, or take prescription medication.

Does VitaMK7 interact with any medications?

Possible interactions include: Warfarin / vitamin-K-antagonists — directly opposes these blood thinners; medical supervision required. Beyond vitamin K antagonists, no other significant drug interactions are well documented — but this is an absence of published data, not a guarantee of safety. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for VitaMK7?

NutraSmarts rates the evidence for VitaMK7 as Moderate (3 out of 5). It is backed by 1 clinical trial and 1 cited reference summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(1 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Knapen MH, Drummen NE, Smit E, et al. Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women. Osteoporos Int. 2013;24(9):2499-507..PubMedUsed to support: 3-year RCT (n=244, 180 mcg/day MK-7) supporting improved vitamin K status and reduced age-related bone loss at the lumbar spine and femoral neck. Bone endpoints only — this reference does not address cardiovascular or arterial outcomes.