Somehow, incredibly, it has been almost four years since I last updated on vitamin K2. There’s a lot to catch up on! Here is an overview of the latest studies and trends.
Exciting new research is adding to the case for vitamin K2 as a breast cancer fighter. Breast cancer is the most prevalent form of cancer worldwide and efforts to improve treatment strategies for patients with the disease are critically important in saving lives. In one study vitamin K2 applied to breast cancer cells in vitro lead to a “dramatic” reduction in cell growth. Other recent papers underline the promising benefits of vitamin K2 for prostate cancer.
Good news for cardiovascular health
Findings from a large clinical study published in 2015 signal vitamin K2 as a potential game changer for cardiovascular health – especially for women. Scientists at the University of Maastricht (the Netherlands) performed a double-blind, randomized, intervention study of 244 postmenopausal women given either 180 mcg of vitamin K2 as MK-7 or a placebo daily for 3 years.
Using ultrasound and pulse-wave velocity measurements to monitor blood flow through the arteries are recognized as important markers for cardiovascular health. Stiff arteries are actually a much better predictor of heart disease than high blood pressure, but blood pressure is easier to measure in your doctor’s office, which is why you may never have heard of arterial stiffness tests. Researchers determined that carotid artery flexibility was significantly improved in study participants taking vitamin K2, especially in women having high-arterial stiffness to begin with. The study also showed vitamin K2 helped increase arterial elasticity.
Finding the RDI
If you’re wondering why the dosage used in the arterial stiffness study (180 mcg) is higher than what is commonly available in supplements (100–120 mcg) that is because Health Canada maintains a somewhat arbitrary limit on K2 supplements dose. The fact that there is currently no established RDI (Recommended Daily Intake) for vitamin K2 compounds the confusion around dosing since there is effectively no baseline. To that end, research has begun in Europe to establish a much-needed RDI for vitamin K2. I’m eagerly awaiting those results and will update you about them here.
About the book
As for the definitive guide to vitamin K2 (a.k.a my book, Vitamin K2 and the Calcium Paradox: How a Little-Known Vitamin Could save Your Life), the English language edition has just entered its 19th printing with well over 100,000 copies sold. It has been translated into 6 languages – the German edition has been particularly successful – and the audio version was released just a couple of weeks ago for your listening pleasure. Believe or not, I mention this less for shameless self-promotion than because I think the books sales reflect and reveal a global trend of still-emerging interest in vitamin K2. So, if you’re among those who already know about K2, you’re ahead of the curve.
 Kiely M, Hodgins SJ, Merrigan BA, et al. Real-time cell analysis of the inhibitory effect of vitamin K2 on adhesion and proliferation of breast cancer cells. Nutr Res. 2015 Aug; 35(8):736-43.
 Dasari S, Ali SM, Zheng G, et al. Vitamin K and its analogs: Potential avenues for prostate cancer management. Oncotarget. 2017 May 19;8(34):57782-57799.
 Knapen MHJ, Braam LAJL, Drummen NE, et al. Menaquinone-7 supplementation improves arterial stiffness in healthy postmenopausal women: double-blind randomised clinical trial. Thromb Haemost. 2015 May: 19:113(5).