Vitamin K2 has received some attention lately, from doctors, dietitians, wellness blogs and supplement manufacturers were quick to jump in and market new K2 pills. Since the publication of the book Vitamin K2 and the Calcium Paradox by Kate Rhéaume-Bleue in 2012, this little known vitamin has become quite the focus as the book asks an important question: is calcium actually killing us?
You probably have discussed calcium and vitamin D supplementation with your doctor, in particular if you are female and over 40. Increasing calcium is good for our bones (fighting osteoporosis), but not so good for our arteries, as they become “calcified”, i.e. the arteries become stiff with calcium deposits. So you end up with a paradox: There is not enough calcium in the bones, but too much in our arteries. So do you take calcium to protect your bones or do you avoid calcium to protect your heart?
Enter vitamin K2. Vitamin K2’s role is to get calcium out of the arteries and into the bones. It does so by activating a protein called osteocalcin which pulls calcium into bones. It also activates matrix GLA proteins (MGPs). These MGPs remove calcium from soft tissue such as arteries, veins and skin.
Vitamin K2 is mainly found in certain animal foods and fermented foods. Natto, a Japanese dish made of fermented soy beans would be a great source. Unfortunately, it is a bit of an acquired taste and I don’t know many Japanese, let alone non-Japanese, who like it.
Rich animal sources include high-fat dairy products from grass-fed cows, liver and other organs, as well as egg yolks. Vitamin K is a fat-soluble vitamin (like vitamins A, D and E), which means low-fat and lean animal product diets don’t help.
Calcium is important for our teeth and bones, but we don’t want to increase the risk for heart disease with calcified arteries. Vitamin K2 could be the answer, so if you are concerned that you are not getting enough vitamin K2 in your diet, you may want to discuss this with your doctor.