A study that included postmenopausal women with low vitamin K status found less blood vessel stiffness among those who received menaquinone-7 (MK-7), a form of vitamin K2.

The current study analyzed 165 premenopausal, perimenopausal and postmenopausal women with low vitamin K status who had participated in a trial that included 243 men and women between 40 to 70 years of age. Eighty-two women received 180 micrograms of MK-7, and 83 women were given a placebo for one year. The participants underwent pulse wave velocity measurement (which evaluated arterial stiffness), carotid artery ultrasound examination, and arterial blood pressure measurement at the beginning and end of the study.

Women who received MK-7 showed improved vitamin K status at the end of one year. Among postmenopausal women (who had worse vascular factors at the beginning of the study than premenopausal and perimenopausal women), vascular stiffness was significantly reduced in the group that received MK-7 compared with the placebo.

The women were subsequently evaluated according to whether they had high or low vascular stiffness at the beginning of the study. Postmenopausal women with a high stiffness index at the beginning of the study, and who received MK-7, had improved blood vessel markers, including lower arterial systolic blood pressure and improved indicators of blood vessel elasticity at the end of the trial.

"Our findings confirm that menopause adversely affects vascular health, leading to an increased vascular stiffness in postmenopausal women," authors Femke de Vries and colleagues wrote. "Notably, postmenopausal women with a heightened arterial stiffness showed the greatest benefit from MK-7 supplementation, experiencing significant improvements in their blood pressure and vascular compliance."

The findings appeared February 27, 2025, in the journal Nutrients.¹