Science / Study - 3
menatto® helps maintain bone health in post-menopausal women*


A randomized, double-blind study found that menatto® vitamin K2 (MK-7) helped with the carboxylation of osteocalcin.* (Carboxylated osteocalcin aids in binding calcium to bone, which supports bone strength and health.*)


Observational studies have suggested a link between consumption of natto (fermented soybean) and bone health. Researchers set out to determine if menatto® (which is derived from natto) could help with the carboxylation of osteocalcin and if so, the effective minimum dose.

Study details

In the first phase of the study, 60 post-menopausal women aged 50 to 69 took 0, 50, 100 or 200 mcg of menatto® per day while eating a controlled diet for 4 weeks. In the second phase, 120 volunteers aged 20-69 took either a placebo or 100 mcg of menatto® daily for 12 weeks. In both phases, circulating carboxylated osteocalcin (cOC) and undercarboxylated osteocalcin (ucOC) were measured at baseline and at the end of the study period.


When volunteers received all their vitamin K from the controlled diet, the ratio of (cOC) to (ucOC) decreased significantly from baseline (in other words, there was less cOC and more ucOC). In the menatto® groups, however, the (cOC) to (ucOC) ratio increased in a dose dependent manner.* Significant effects were noted at 100 and 200 mcg. The researchers suggest 100 mcg of menatto® or more per day to help maintain bone health.* Importantly, 100 mcg of menatto® did not affect normal blood coagulation.

Inaba N, Sato T, Yamashita T. J Nutr Sci Vitaminol. 2015;61:471-80.