Vitamin K for the primary prevention of cardiovascular disease.

Systematic review of randomized trial evidence for primary prevention of cardiovascular disease, with one included study in apparently healthy adults from the Netherlands. Participants were adults aged 40 to 65 years with BMI 18.5 to 30, and the active MK-7 arms randomized 22 participants to 180 µg/day and 19 to 360 µg/day.

Vitamin K2 as menaquinone-7 (MK-7) was given orally for 12 weeks in two active regimens: 180 µg/day as one MK-7 capsule plus one placebo capsule daily, or 360 µg/day as two MK-7 capsules daily. The comparator was placebo capsules containing linseed oil.

Vitamin K2 (MK-7) did not show meaningful effects on blood pressure or lipid levels over 12 weeks, and no clinical cardiovascular outcomes were reported. In the 180 µg/day arm, the mean difference versus placebo was -6.75 for systolic blood pressure, 0.0 for diastolic blood pressure, 0.20 for total cholesterol, 0.0 for LDL-C, 0.0 for HDL-C, and 0.1 for triglycerides. In the 360 µg/day arm, the corresponding mean differences were 1.74, 2.32, -0.10, 0.20, 0.0, and 0.1. The evidence base is extremely limited, so no firm conclusion can be drawn about vitamin K for primary prevention of cardiovascular disease.

Evidence came from only one small randomized trial with short 12-week follow-up, so clinical cardiovascular prevention cannot be assessed. Outcomes were limited to risk factors, adverse events were not reported, and the population was restricted to relatively healthy adults from the Netherlands, limiting generalizability.