A recent review published by researchers in the Netherlands-based Maastricht University examined recent clinical evidence regarding the unique functions vitamin K2 has within the human body, and argued that vitamin K2 needs to be granted an RDI (recommended daily intake) separate from vitamin K1 by governing bodies around the globe.
 
The vitamin K family plays an essential role in coagulation, which has been well established by decades-long research. However, in the past few decades, the role of vitamin K- dependent proteins in processes beyond coagulation have been discovered and well-substantiated, the authors wrote.
 
The vitamin K family is broken down into two types of molecules. K1, as it has become commonly known, is phylloquinone, and is found mainly in leafy green vegetables. K2 is made up of menaquinones, which can be further classified into the subtypes MK-4, MK-7, MK-8, and MK-9. Menaquinones are found in high concentrations mainly in fermented foods, such as natto, which is common in Japan, but K2 is largely absent in most diets around the globe, and K2 deficiency is ubiquitous. The almost 1,000 years in which Japanese cuisine has incorporated natto, the world’s richest food source of vitamin K2, could also prove to leverage prospective cohort studies on bone loss and fracture risk in comparison to other countries, the authors said, indicating that some of these studies have already taken place.
 
While vitamin K1’s biological mechanisms take place within the liver, an abundance of beneficial mechanisms take place throughout the body as a result of ingesting vitamin K2, including better calcification of bones, and the prevention of arterial stiffness. In layman’s terms, it inhibits calcification from occurring within veins and arteries, promoting greater arterial flexibility, while also preventing bone degeneration to the extent that it has been shown in population-based clinical trials to improve outcomes for osteoperosis. Further preliminary research evidences its efficacy  at improving outcomes for atherosclerosis, cancer, and inflammatory diseases, and that K2 plays an important role in endothelial function.
 
The two families, K1 and K2, are distinguishable through the use of high-performance liquid chromatography (HPLC), which has become the standard method in Europe and other regions.
 
NattoPharma, a company that produces the only vitamin K2 as MK-7 product on the market, MenaQ7, has been a leader in supporting the research, clinical substantiation, and international patents on MK-7, and weighed in on their own pursuits to reach a K2-specific RDI in relation to the review, an endeavor which dates back to 2018. The company supported the review in discussion.
 
“NattoPharma announced its intention to spearhead the pursuit of a K2-specific RDI in 2018,” the company said in a statement. “The program began with a team of researchers in Maastricht University, the Netherlands, the group that has led the way to discovering and validating the health benefits of Vitamin K2, guided by Dr. Leon Schurgers, professor of Biochemistry of Vascular Calcification and vice chair of Biochemistry at the Cardiovascular Research Institute Maastricht (CARIM), Maastricht University. NattoPharma has worked closely with the Maastricht University in documenting benefits of the company’s exclusive branded MenaQ7 vitamin K2 as MK-7, since 2004 – work that has been recognized with many peer-reviewed scientific papers and with recently awarded research grants.”
 
“We have been working with Maastricht University for almost two decades validating the health benefits of Vitamin K2, creating this category,” Kjetil Ramsøy, NattoPharma CEO, said. “Our work, in addition to others’, is building the necessary body of evidence required to convince regulatory bodies how essential Vitamin K2 is for the betterment of global human health. This is no small undertaking, yet we at NattoPharma believe it is vital we reach a global recommendation for K2 intakes if we are to correct the K2 deficiency that has so negatively impacted the bone and cardiovascular health, and correcting this deficiency can benefit men and women, adults and children.”
 
A number of research grants have been awarded to CARIM from the European Union’s Horizon 2020 program, which have been and will be used to host PhD students in order to foster a further understanding of the RDI values set by the U.S. Food and Drug Administration and the European Food Safety Authority.
 
“These [PhD students] utilized this knowledge as they conducted a comprehensive literature review elucidating the data for K2’s bone and cardiovascular benefits,” NattoPharma said. “This cogent argument will work towards the efforts of petitioning for RDIs.”