Dr. Kumar’s Take:
This large Dutch study found that higher dietary intake of vitamin K2—not K1—was associated with a lower risk of coronary heart disease in postmenopausal women. The benefit was strongest for the longer-chain forms of vitamin K2 (MK-7, MK-8, and MK-9), which are mainly found in fermented foods and certain cheeses. If you’re focused on heart health, incorporating K2-rich foods or considering supplementation may be worth discussing with your doctor.
Key Takeaways:
✔ Vitamin K2 intake was linked to a 9% lower risk of heart disease for every 10 mcg consumed daily.
✔ The benefit came mostly from MK-7, MK-8, and MK-9—longer-chain types of K2.
✔ Vitamin K1 (found mostly in leafy greens) showed no protective effect against heart disease.
✔ K2-rich foods included cheese, dairy, and meat products.
✔ Women with higher K2 intake had less heart disease over 8 years of follow-up.
Actionable Tip:
Add vitamin K2-rich foods like aged cheese (Gouda, Edam), fermented soy (natto), and egg yolks to your weekly meals—or talk to your healthcare provider about a K2 supplement containing MK-7 or MK-9.
Brief Summary:
Researchers analyzed data from 16,057 postmenopausal Dutch women who were followed for over 8 years. They found that those with higher intakes of vitamin K2 had significantly fewer cases of coronary heart disease (CHD). The protective effect was most pronounced with the K2 subtypes MK-7, MK-8, and MK-9. Vitamin K1, in contrast, did not show a benefit. These findings suggest that vitamin K2 may help prevent arterial calcification, a key contributor to heart disease.
Study Design:
This was a prospective cohort study using data from the Dutch PROSPECT-EPIC study. Over 16,000 women aged 49–70 were enrolled between 1993 and 1997 and followed for an average of 8.1 years. Participants completed detailed food frequency questionnaires to assess their intake of vitamins K1 and K2. The researchers then tracked incidents of coronary heart disease using national hospital and death registries. Multiple models adjusted for age, lifestyle factors, and dietary variables.
Results:
- Higher vitamin K2 intake was associated with a lower risk of heart disease (HR: 0.91 per 10 mcg/day).
- Vitamin K2 subtypes MK-7, MK-8, and MK-9 showed the strongest protective associations.
- Vitamin K1 intake had no significant impact on heart disease risk.
- The results held up after adjusting for age, smoking, diabetes, cholesterol, hypertension, and calcium intake.
How Vitamin K2 May Protect the Heart
Vitamin K2 helps activate proteins like Matrix Gla Protein (MGP), which prevents calcium buildup in the arteries. Without enough K2, these proteins remain inactive, allowing calcium to deposit in blood vessels—a major factor in heart disease. Unlike vitamin K1, which mainly supports blood clotting, K2 is better absorbed by arterial tissue and may directly reduce calcification.
Related Studies and Research
Explores how vitamin K2 may influence heart disease outcomes, focusing on arterial stiffness and calcification. – Core summary of K2’s cardiovascular mechanisms and clinical evidence.
A comprehensive 2023 review of vitamin K2’s roles in cardiovascular, bone, and metabolic health. – In-depth analysis of the latest findings on K2 across multiple health domains.
Assesses MK-7’s influence on anticoagulation therapy stability and potential dose–response effects. – Evaluates how MK-7 dosing modulates INR and bleeding risk in patients on vitamin K antagonists.
Examines how warfarin use is linked with increased arterial calcification risk due to vitamin K inhibition. – Investigates warfarin’s unintended impact on vascular calcium deposition.
Meta-analysis showing vitamin K’s effect on arterial calcification progression in different populations. – Pooled results quantifying the effect of K supplementation on calcification scores.
Frequently Asked Questions
What foods are highest in vitamin K2?
Cheeses (like Gouda, Edam, and Brie), fermented foods like natto, meat, egg yolks, and dairy are good sources—especially of the MK-7 to MK-9 forms.
How is K2 different from K1?
K1 (phylloquinone) is found in green vegetables and mostly supports blood clotting. K2 (menaquinone) is better absorbed by other tissues and helps prevent calcium buildup in arteries.
Should I take a vitamin K2 supplement?
If you’re at risk for heart disease or have low dietary intake of K2, a supplement (often MK-7) may be helpful. Always consult your doctor before starting any new supplement.
Can I get enough K2 from food?
Possibly, if you regularly eat aged cheeses, natto, or other fermented animal products. However, many Western diets are low in these foods.
Conclusion
This study adds to the growing evidence that vitamin K2—especially its longer-chain forms like MK-7, MK-8, and MK-9—may help reduce the risk of coronary heart disease by protecting arteries from calcium buildup. While vitamin K1 plays a vital role in blood clotting, it does not appear to offer the same heart-protective effects. Including K2-rich foods or supplements may be a promising and natural approach to heart health.