Dr. Kumar’s Take:
This 3-year randomized study adds strong evidence that daily low-dose Vitamin K2 (MK-7) can help reduce bone loss in postmenopausal women. The supplement improved markers of vitamin K status, preserved bone mineral density in the spine, and improved femoral bone strength compared to placebo. These benefits took time—only emerging after 2–3 years—so consistency and patience are key.
If you’re postmenopausal and looking for non-drug ways to support bone health, this is a compelling case for adding MK-7 to your routine.
Key Takeaways:
✔ 180 µg of MK-7 daily significantly improved bone health over 3 years
✔ Spine and femoral neck bone density loss was slowed in the MK-7 group
✔ Markers of vitamin K status improved, showing better osteocalcin activation
✔ No major side effects were reported, and supplement compliance was high
Actionable Tip:
Consider adding 180 µg of MK-7 (menaquinone-7) daily, especially if you are postmenopausal and concerned about bone loss. Choose a supplement with verified stability and quality.
Brief Summary:
This 3-year, double-blind, placebo-controlled trial followed 244 healthy postmenopausal women who received either placebo or 180 µg/day of MK-7 (menaquinone-7). Bone density in the lumbar spine and femoral neck declined more slowly in the MK-7 group, and bone strength improved. The supplement also significantly improved vitamin K status by reducing uncarboxylated osteocalcin (ucOC), a marker of poor vitamin K status, by over 50%. No significant effects were seen in total hip BMD, and changes in vertebral fracture rates were too rare for statistical comparison.
Study Design:
- Type: 3-year randomized, double-blind, placebo-controlled trial
- Participants: 244 healthy postmenopausal women (55–65 years old)
- Groups: Placebo vs. 180 µg/day MK-7 (MenaQ7)
- Measurements: Bone mineral density (BMD), bone mineral content (BMC), vertebral fracture assessment, and blood levels of osteocalcin (ucOC and cOC)
- Compliance: High, with 97% adherence rate
Results:
Vitamin K status improved:
- ucOC decreased by ~51%
- cOC increased by ~21%
- ucOC/cOC ratio improved by 58%
Bone mineral density:
- Slower decline in lumbar spine and femoral neck BMD
- No change in total hip BMD
- Lumbar spine BMD remained nearly stable in MK-7 group
Bone strength indices (femoral neck):
- Compression strength and impact strength improved in the MK-7 group
- No change in hip geometry
Fractures:
- Very few new vertebral fractures occurred
- Mid-site vertebral height loss (T10–T12) was lower in MK-7 group (−3.3% vs. −4.1%, p = 0.003)
How Vitamin K2 (MK-7) Supports Bone Health
Vitamin K2 helps activate proteins that regulate bone formation and prevent calcification in the wrong places. It does this through a process called carboxylation, which allows proteins like osteocalcin to bind calcium properly in bone. MK-7 is a long-chain form of K2 with better absorption and longer half-life compared to K1 and MK-4, making it ideal for maintaining consistent activation of these proteins.
MK-7 may also reduce bone breakdown by suppressing inflammatory pathways such as NF-κB activation, independent of carboxylation.
Related Studies and Research
Three-year RCT evaluating low-dose MK-7’s impact on bone loss in healthy postmenopausal women. – Core trial assessing MK-7’s capacity to preserve bone mass.
Comprehensive meta-analysis of randomized trials on MK-7 supplementation and osteoporosis prevention in postmenopausal women. – Meta-level evidence of K2’s bone benefits.
Analysis of warfarin therapy’s relationship with increased osteoporotic fracture risk in elderly atrial fibrillation patients. – Evaluates fracture risk under anticoagulation.
Examines warfarin’s influence on bone mineral density reduction and fracture incidence. – Detailed look at BMD declines with warfarin.
Population-based study linking habitual natto consumption to higher bone density in elderly Japanese women. – Observational link between natto and bone density.
Frequently Asked Questions
Is MK-7 a better supplement than MK-4?
Yes. MK-7 supplementation is highly abosorbale orally, stays in the body longer, and is more effective at improving vitamin K status. But there is ample evidence that MK-7 is converted to MK-4 in the body to achieve the benefits of Vitamin K2. Why not just take MK-4? Well… MK-4 may be the main usble form of Vitamin K2 in the body, but its very poorly absorbed orally.
How long do I need to take MK-7 to see benefits?
The study showed measurable benefits only after 2–3 years. MK-7 is a long game supplement—it works gradually but steadily.
Are there any risks or side effects?
No serious side effects were reported in this study. Minor complaints like rash or hot flashes were rare.
Can MK-7 be taken with calcium or vitamin D?
Yes. Though this study didn’t include calcium or D supplementation, combining them is common and may be synergistic.
Conclusion
Long-term supplementation with MK-7 (180 µg/day) is a safe and effective way to slow age-related bone loss in healthy postmenopausal women. It improves vitamin K status, supports bone strength, and may help reduce vertebral deterioration over time. This study provides strong support for MK-7 as a daily addition to bone health regimens.