In a recently published study by Emaus et al. at the University of Tromsø (Osteoporos. Int. 2009, Epub ahead of print), the effect of vitamin K2 on bone loss in women in early menopause was measured. 334 healthy women between 50 and 60 years old were divided into two groups, one group received 360μg MK-7 capsule and the other group received placebo capsules. After 1 year of study, the treatment group demonstrated a positive change in the biochemical markers related to improved bone health. No significant difference was found in bone loss or bone mass between the two groups. Emaus et al. therefore draw the conclusion that vitamin K2 has no effect on bone loss in women between 50-60 years old.
It is a fact that changes in biochemical markers appear faster than changes in bone mass. NattoPharma therefore believes that if the study had stretched over longer time, one would most likely have seen a positive result also in bone mass.
NattoPharma sees that some Norwegian media has recently referred to the Emaus study and concluded that there is no association between vitamin K2 and bone health. NattoPharma believes this creates unnecessary uncertainty among consumers. Experts in vitamin K research recommend strongly, based on worldwide research results over the past decade, all people to take vitamin K2 for general bone health. Based on all relevant studies and thorough evaluation by experts in this field, the authorities in the EU has also concluded that there is a positive association between intake of vitamin K2 and good bone health.
NattoPharma has received a comment regarding the results of Emaus et al from Dr. Cees Vermeer at VitaK BV, Maastricht University, a respected and experienced vitamin K researcher at the world's leading vitamin K research center: "In a new review of Iwamoto et al. (2009) the minimum criteria for studies of vitamin K and bone health are defined (Iwamoto, J. et.al., 2009. High-dose vitamin K supplementation reducer Fracture incidences in postmenopausal women: a review of the literature. Nutr. Res. 29: 221-8).
These criteria are:
- A minimum of 50 persons per study arm
- A minimum study duration of 2 years (preferably longer).
Many studies have been published that do not meet these criteria, and one of them is the recently published study by Emaus et al (2009). Studies in which changes in biomarkers are used as endpoints may be 3-6 months, while those using bone mineral density (BMD) as a clinical endpoint should be longer than 2 years. I expect that an extension of the study by another 2 years would have shown a positive effect of vitamin K2 in bone density and bone strength. "
Dr. Leon Schurgers, VP R&D in NattoPharma, explains that this is why NattoPharma has chosen a 3-year randomized clinical trial to demonstrate the effect of MenaQ7, NattoPharma's vitamin K2. Dr. Schurgers elaborates further: "All vitamin K intervention trials lasting less than 2 years have unfortunately contributed to confusion regarding the effect of vitamin K supplements. The study of Emaus et al is no exception."