Healthy Origins Vitamin K2 (from Natto) provides Vitamin K2 in its most biologically active form called Menaquinone-7 or MK-7 for short. Vitamin K2 as MK-7 has superior absorption and retention in the body when compared to Vitamin K1 – the typical supplemental form. Natural Vitamin K2 may help to support bone healt. cardiovascular healt. calcium metabolism and arterial health.