Vitamin K2 (menaquinones)

Specific molecules

The form of vitamin K made by bacteria, not by plants.

Natto provides dozens of times more than everything else, in a form (MK-7) that stays in the blood a long time.

Effects and benefits

The vitamin K made by bacteria, not plants. Like all vitamin K, it contributes to normal blood clotting and bones; it also activates the protein that fixes calcium in bone, and another that keeps it from settling in the arteries.

Vitamin K activates proteins by grafting a calcium clamp onto them. Osteocalcin, once activated, fixes calcium in bone; the MGP protein, activated too, keeps calcium from settling in the artery wall (Schurgers et al., 2007).

Vitamin K contributes to normal blood clotting and to the maintenance of normal bones (Regulation 432/2012).

In the Rotterdam study, a high K2 intake was associated with less calcification of the arteries and fewer cardiovascular deaths (Geleijnse et al., 2004): an association. With a vitamin K antagonist anticoagulant, what matters is steady intake, to discuss with your doctor.

Sources: Schurgers et al., Blood, 2007 · EU Regulation 432/2012 · Geleijnse et al., J Nutr, 2004

Where to find it (1)

• Natto

Also, in smaller amounts (9)

• Cheese aged < 3 months
• Crème fraîche
• Gochujang / doenjang
• Kefir
• Miso
• Other fermented vegetables
• Skyr
• Tempeh
• Yogurt