Will vitamin K2 get an official RDI?

Every vitamin and mineral has a Reference Daily Intake, or Daily Value—the minimal amount required so the body does not succumb to a deficiency disease. For vitamin C, it’s 90 mg/day, or scurvy may come to your lips. For vitamin D, it’s 800 IU/day, or rickets to your bones. For magnesium it’s about 400 mg/day (varies by age and gender), or muscle weakness and cramps.

And yet, vitamin K2—the forgotten vitamin—still has not received its imprimatur from the Institute of Medicine.

Dozens of studies have been published demonstrating vitamin K2’s effect on cardiovascular and bone health. K2 helps the body place calcium by activating two critical proteins—osteocalcin, which brings calcium to bones, and matrix GLA, which takes calcium out of arteries.

Studies have revealed that a vitamin K2 deficiency induces calcification. K2 you can inhibit that and even reverse arterial calcification and therefore cardiovascular death.

The latest study is explicit that its findings identifying the specific benefits and mechanism of action for vitamin K2 make the case for an RDI.

“In this review,” the authors write, “we highlight the specific activity of vitamin K2 based upon proposed frameworks necessary for a bioactive substance to be recommended for an RDI. Vitamin K2 meets all these criteria and should be considered for a specific dietary recommendation intake.”

NattoPharma driving research and campaign

Ingredient supplier NattoPharma has sponsored most of the research around vitamin K2, mostly at Maastricht University in the Netherlands, with its branded MenaQ-7 ingredient. The collaboration between NattoPharma and Maastricht University dates to 2004. In 2018 the two announced their intentions to spearhead the pursuit of a K2-specific RDI, and have since published four additional studies.

While this study makes a full-throated case for a K2 RDI, it’s actually just a step in the process to get it done. NattoPharma plans on calling attentive on to the vitamin and its campaign to attain RDI status at conferences and exhibitions within the nutrition segment in order to build endorsements and momentum for when it takes its case to the IOM.

Another study, currently underway, is exploring K2’s potential therapy for patients who express intense calcification as a symptom of their condition. Being able to show a vitamin is a viable therapy where drugs have failed to provide relief, the thinking goes, could go a long way to convincing governing bodies that K2 does indeed need its own RDI as a means of correcting a global deficiency. \

K2 benefits

Vitamin K is known for its coagulation effects on blood. K2 goes well beyond K’s effects. A few landmark studies really put K2 on the map, in particular the long-chain menaquinone-7 form, which has a much longer half life and is seen as being much better than the MK-4 version.

In one early observational study from 2004, over 10 years, those with the highest intake of vitamin K2 were 52 percent less likely to develop arterial calcification—the harbinger of atherosclerosis, or hardening of the arteries, the top cardio killer—and had a 57 percent lower risk of dying from heart disease.

In a landmark study, from 2015, researchers showed patients with hardening of the arteries actually experienced a reversion of the condition. While early studies showed 45 mcg/day was an effective dose, a much higher dose of 360 mcg/day was used in this study to improve arterial flexibility. That suggested the cardiovascular condition may be due to a deficiency of the vitamin.

A 2019 study delineated the differences between isoforms vitamin K1 and K2, with researchers showing vitamin K2 to regulate osteoporosis, atherosclerosis, cancer and inflammatory diseases.

“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,” said Kjetil Ramsøy, NattoPharma CEO. “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.”

It’s notable that omega-3 fatty acids have hundreds of published studies, and still no RDI to show for it. Can K2 make the cut with a much smaller scientific dossier? It does help mightily that it is recognized as a bona fide vitamin. The science is compelling, and the case continues to build.