Presenting the findings, Maastricht University researcher Dr. Leon Schurgers described the VitaK-CAC study as part of a much longer effort to understand whether vitamin K could influence calcium deposits in blood vessels.
“Vitamin K became really the story of my life,” he told presentation attendees.
Dr. Schurgers initially studied vitamin K in relation to bone health before turning his attention to the blood vessels, where calcium buildup can contribute to arterial stiffness.
He recalled approaching cardiologists about studying vitamin K’s potential to prevent calcification, only to be told that the process was irreversible.
“We are talking 25 years ago,” he said. “There was nothing about healthy food and healthy living.”
Building the evidence
Dr. Schurgers’ research has included matrix Gla protein (MGP), which depends on vitamin K to help protect blood vessels from calcium deposits.
Some of the earliest evidence came from animal experiments. In early experiments, animals lacking a functioning MGP protein developed extensive calcification in their arteries.
Dr. Schurgers also examined the link between vascular calcification and vitamin K antagonists, drugs used to prevent blood clots by interfering with vitamin K activity.
His presentation then turned to the VitaK-CAC trial, published in JAMA Cardiology, which tested whether MK-7 supplementation could slow existing coronary artery calcification.
The researchers enrolled 180 patients with coronary artery disease. Half were assigned 360 mcg of MK-7 daily and half received a placebo, with 150 completing the two-year study.
CT scans at the start of the study and during follow-up measured how quickly calcification progressed.
Slower calcium buildup
As detailed in the presentation, participants taking MK-7 had a 29% lower increase in coronary artery calcium scores than the placebo group, and calcium mass accumulation was also approximately 42% lower.
Researchers also measured circulating vitamin K levels and dephosphorylated-uncarboxylated matrix Gla protein (dp-ucMGP), a marker of vitamin K status. MK-7 supplementation significantly increased circulating MK-7 levels and limited the rise in dp-ucMGP compared with placebo.
Dr. Schurgers highlighted that the study investigated MK-7 alone, unlike other trials that have combined vitamin K2 with vitamin D3.
“It attenuated the progression of the calcification of coronary arteries, but also it reduced new coronary artery calcification,” he said.
The researchers suggested that MK-7’s effect was most evident in developing plaques, where it may have slowed the transition from noncalcified to partially calcified lesions. However, the study did not establish whether this translates into improved cardiovascular outcomes.
He also pointed to research from Denmark examining vitamin K2 alongside vitamin D3, which reported slower calcification progression.
Questions for future studies
Although the findings were encouraging, Dr. Schurgers acknowledged that nutritional research often lacks the resources needed for large clinical trials.
“We have to work with 180 people, two years, low budget,” he said.
He noted that future studies should investigate optimal dosing and whether certain populations are more likely to respond to vitamin K supplementation.
“What is the optimal dose? We gave 360. Is that enough? We should test that,” he said.
Dr. Schurgers also called for researchers to distinguish between responders and non-responders, particularly among people with poor vitamin K status or underlying health conditions.
The researchers noted that larger studies measuring clinical outcomes will be needed to establish whether slowing coronary artery calcification translates into meaningful cardiovascular benefits.
Source: JAMA Cardiology 2026;11;(8):719-726. doi:10.1001/jamacardio.2026.1279 “Two Years of Menaquinone-7 Supplementation and Coronary Artery Calcification” Authors: Vossen, L.M. et al
