Coronary artery calcification (CAC) occurs when calcium deposits build up in the walls of the coronary arteries, which supply blood to the heart. Although most calcium is found in teeth and bone, approximately 1% is dissolved in the bloodstream. As the human body ages, calcium can be deposited in various body parts. This process is generally considered part of normal ageing.
Over time, these calcium deposits can harden and narrow the arteries, contributing to a condition known as atherosclerosis. 1
What influences Coronary Artery Calcification?
Coronary artery calcification (CAC) is influenced by a combination of biological, age-related, and lifestyle factors. In postmenopausal women, reduced estrogen levels increase susceptibility to CAC, as estrogen normally confers vascular protection by supporting endothelial function and limiting oxidative stress. Aging itself is an independent risk factor, driven by chronic low-grade inflammation, progressive endothelial dysfunction, and a decline in endogenous inhibitors of vascular calcification such as matrix Gla protein (MGP).
In addition, lifestyle factors play a critical role; physical inactivity, diets high in saturated fats, cholesterol, and refined sugars, and excessive alcohol consumption promote hypertension, dyslipidemia, and obesity, all of which accelerate the development and progression of coronary artery calcium. 1,2
Nutritional Interventions for Cardiovascular Health:
Vitamin K’s beneficial actions on cardiac and vascular function
Cardiovascular health is strongly influenced by dietary patterns and nutritional quality. Beyond macronutrient composition, specific bioactive food components such as essential fatty acids from fatty fish, seaweed, chia or flax seeds and polyphenols found in berries, nuts, and multicolored fruits and vegetables, have been shown to exert cardioprotective effects, with growing evidence supporting their ability to lower blood pressure, improve lipid metabolism, and promote vascular endothelial regeneration. 3
Vitamin K also plays an important role in regulating vascular function and potentially slowing the progression of calcification. Epidemiological studies have shown associations between lower vitamin K status and increased risks of coronary heart disease and hypertension, suggesting vitamin K may be beneficial for cardiovascular health. 4
The Difference of Vitamin K1 and K2
Vitamin K is a family of fat-soluble vitamins that exist in two primary forms: phylloquinone (vitamin K1), found predominantly in leafy green vegetables, and menaquinones (vitamin K2), including menaquinone-7 (MK-7), which are present in smaller amounts in foods such as meats and dairy products. Both vitamin K1 and vitamin K2 serve as cofactors for the activation of vitamin K–dependent proteins (VKDPs). Scientific evidence suggests that the metabolism and tissue distribution of these forms may differ. Vitamin K1 is primarily utilized by the liver to support normal blood coagulation function, whereas vitamin K2 is more readily distributed to extrahepatic tissues, including bone and vascular tissue, to support physiological structure and function. Among the vitamin K forms, MK-7 has been reported to have greater bioavailability and a longer circulating half-life. 5,6
Despite its importance, dietary intake of vitamin K2 (especially in Western populations,) is often insufficient to fully activate matrix Gla protein (MGP), a key inhibitor of calcification.
MK‑7 intake is generally low in Western diets, as it is primarily in fermented foods such as natto and only present in limited amounts in commonly consumed foods. While meat and dairy products do provide vitamin K2, they contain primarily other forms rather than MK‑7. To reach adequate vitamin K2 levels from meat and dairy alone, very large quantities would need to be consumed, which is neither practical nor desirable and may be associated with adverse health effects. Therefore, MK‑7 represents an important and efficient way to support sufficient vitamin K2 intake.
highlighting the growing interest in targeted nutritional strategies to support long-term bone and cardiovascular health. 5
How Vitamin K2 works in the Body
Vitamin K2 Directs Calcium Where It Belongs
Vitamin K2 activates key vitamin K dependent proteins that guide calcium into bones while preventing its accumulation in arteries and soft tissues.
How Does Vitamin K2 Activate MGP to Benefit Blood Vessels
Through a process called carboxylation, vitamin K2 converts matrix Gla protein (MGP) into its active form that can prevent calcium from depositing in soft tissues, which helps maintain normal calcium balance within the vascular system. When vitamin K levels are low, MGP remains inactive. This inactive form (known as dp-ucMGP,) can be measured in the blood and is widely used as a marker of poor vitamin K status. Higher levels of dp-ucMGP are linked to increased calcium buildup in blood vessels, which can lead to arterial stiffness and contribute to vessel wall and plaque calcification.
How Vitamin K2 Supports Strong and Healthy Bones
Vitamin K2 is important for activating osteocalcin, a protein required for bone mineralization. Activated osteocalcin enhances bone density while also helping prevent calcium and phosphate from depositing in soft tissues.
The Relationship between Vitamin K2 and D
From a mechanism of action, Vitamin D increases intestinal calcium absorption and stimulates the production of vitamin K–dependent proteins (such as MGP). However, MGP requires vitamin K2 for activation; without adequate K2, vitamin D driven calcium metabolism may promote calcium deposition in arterial walls rather than directing it safely to bone. 4 Together, they work synergistically to regulate calcium metabolism and support a healthy vascular system.
How Vitamins K2 and D Are Shaping Cardiovascular Nutrition
Growing clinical evidence continues to position vitamins K2 and D as important contributors to cardiovascular health, particularly through their role in calcium regulation. This body of research is anchored by the Aortic Valve Decalcification (AVADEC) trial, a multicenter, double-blind, placebo-controlled study conducted across four Danish hospitals. AVADEC evaluated 389 older men (mean age 71) with no prior cardiovascular surgery or medication use, randomized to receive vitamin K2 (MK-7, 720 µg/day) and vitamin D3 (25 µg/day) or placebo for 24 months.
Using blood biomarkers (dp-ucMGP) and advanced cardiac CT imaging, researchers demonstrated that combined vitamin K2 and D supplementation favorably influenced coronary artery calcium progression—a key marker of cardiovascular disease risk. In a sub-group analysis with 304 males, where combined K2 and D3 supplementation significantly slowed coronary artery calcium progression in high-risk individuals with baseline CAC scores above 400, a result not previously achieved in randomized controlled trials. To further validate these results, the ongoing DANCODE trial is now investigating MK-7 and vitamin D supplementation in both men and women with elevated CAC scores, aiming to strengthen the clinical foundation for targeted cardiovascular nutrition strategies. 5,7,8
