A high menaquinone intake reduces the incidence of coronary heart disease

Background and Aim: Vitamin K dependent proteins have been demonstrated to inhibit vascular calcification. Data on the effect of vitamin K intake on coronary heart disease (CHD) risk, however, are scarce. To examine the relationship between dietary vitamins K₁ and K₂ intake, and its subtypes, and the incidence of CHD. Methods and Results: We used data from the Prospect-EPIC cohort consisting of 16,057 women, enrolled between 1993 and 1997 and aged 49-70 years, who were free of cardiovascular diseases at baseline. Intake of vitamin K and other nutrients was estimated with a food frequency questionnaire. Multivariate Cox proportional hazards models were used to analyse the data. After a mean ± SD follow-up of 8.1 ± 1.6 years, we identified 480 incident cases of CHD. Mean vitamin K₁ intake was 211.7 ± 100.3 μg/d and vitamin K₂ intake was 29.1 ± 12.8 μg/d. After adjustment for traditional risk factors and dietary factors, we observed an inverse association between vitamin K₂ and risk of CHD with a Hazard Ratio (HR) of 0.91 [95% CI 0.85-1.00] per 10 μg/d vitamin K₂ intake. This association was mainly due to vitamin K₂ subtypes MK-7, MK-8 and MK-9. Vitamin K₁ intake was not significantly related to CHD. Conclusions: A high intake of menoquinones, especially MK-7, MK-8 and MK-9, could protect against CHD. However, more research is necessary to define optimal intake levels of vitamin K intake for the prevention of CHD.