There’s no doubt that beyond building strong bones, calcium is incredibly important. It plays a key role in cell signaling, blood clotting, and muscle contractions—including that most important muscle, the heart.
But as we get older, calcium can also build up in the heart and the arteries. As you can imagine, this condition makes the arteries stiff and inflexible. It also increases the risk of blood clots, strokes, and heart attacks.
Fortunately, research shows that vitamin K2 can help keep calcium in its proper places and in the right proportions. Two Dutch studies have reported encouraging results. One found that individuals with a higher dietary intake of vitamin K2 had a lower risk of death from coronary heart disease.
One reason for this is that vitamin K2 activates naturally occurring proteins in the body, including matrix GLA-protein (MGP) and osteocalcin to inhibit the mineral’s accumulation in the body, and help it absorb into the bones to keep them strong.
Additionally, vitamin K2 has been shown to reduce circulating levels of an inactive form of MGP (dp-ucMGP) that would otherwise lead to calcium deposits in the arteries. For in women in menopause who were especially at risk, vitamin K2 cut the levels of harmful dp-ucMGP in half and reduced arterial stiffness as well.
Knapen MH, Braam LA, Drummen NE, Bekers O, Hoeks AP, Vermeer C. Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women. A double-blind randomised clinical trial. Thromb Haemost. 2015 May;113(5):1135-44.
Observational data suggest a link between menaquinone (MK, vitamin K2) intake and cardiovascular (CV) health. However, MK intervention trials with vascular endpoints are lacking. We investigated long-term effects of MK-7 (180 µg MenaQ7/day) supplementation on arterial stiffness in a double-blind, placebo-controlled trial. Healthy postmenopausal women (n=244) received either placebo (n=124) or MK-7 (n=120) for three years. Indices of local carotid stiffness (intima-media thickness IMT, Diameter end-diastole and Distension) were measured by echotracking. Regional aortic stiffness (carotid-femoral and carotid-radial Pulse Wave Velocity, cfPWV and crPWV, respectively) was measured using mechanotransducers. Circulating desphospho-uncarboxylated matrix Gla-protein (dp-ucMGP) as well as acute phase markers Interleukin-6 (IL-6), high-sensitive C-reactive protein (hsCRP), tumour necrosis factor-α (TNF-α) and markers for endothelial dysfunction Vascular Cell Adhesion Molecule (VCAM), E-selectin, and Advanced Glycation Endproducts (AGEs) were measured. At baseline dp-ucMGP was associated with IMT, Diameter, cfPWV and with the mean z-scores of acute phase markers (APMscore) and of markers for endothelial dysfunction (EDFscore). After three year MK-7 supplementation cfPWV and the Stiffness Index βsignificantly decreased in the total group, whereas distension, compliance, distensibility, Young’s Modulus, and the local carotid PWV (cPWV) improved in women having a baseline Stiffness Index β above the median of 10.8. MK-7 decreased dp-ucMGP by 50 % compared to placebo, but did not influence the markers for acute phase and endothelial dysfunction. In conclusion, long-term use of MK-7 supplements improves arterial stiffness in healthy postmenopausal women, especially in women having a high arterial stiffness.
Vermeer C, Vik H. Effect of Menaquinone-7 (vitamin K2) on vascular elasticity in healthy subjects: results from a one-year study. Vascul Dis Ther. 2020 5:3-4.
Background: Matrix Gla-Protein (MGP) is involved in the prevention of arterial calcification. During vitamin K-insufficiency, MGP is produced in its inactive form: dp-ucMGP. Two 3-year intervention studies in the general population have shown that increased vitamin K intake may decrease arterial stiffening, but the difference with placebo became only significant in the third year of treatment. In the present trial we have investigated whether in a pre-selected group of vitamin K-insufficient subjects (men and women) an effect of vitamin K-supplementation may be demonstrated within one year.
Methods: A randomized placebo-controlled clinical trial was performed in 243 subjects (40-70 years old) characterized by circulating dp-ucMGP concentrations above the median of the general population. Arterial stiffness was concluded from the carotid-femoral pulse-wave velocity (cfPWV), and other vascular characteristics were measured by echotracking of the common carotid artery. Treatment was performed with either vitamin K (menaquinone-7, MK-7) or placebo for one year.
Results: In the total study group, MK-7 induced a significant decrease of both dp-ucMGP and cfPWV. After subdividing by gender, it appeared that the effects were only seen in women, in whom we also found beneficial effects in other vascular characteristics as well as in body weight and BMI.
Conclusions: High vitamin K intake decreased age-related vascular stiffening. The effects were most obvious in women with poor vitamin K status and were statistically significant after one year of treatment.