Vitamin K2, or menaquinone, has garnered increasing amounts of attention in recent years. It is famous as BONE BUILDER, as it is reported to help maintain bone strength by affecting the formation of osteoclasts, the cells responsible for breaking down bone. Studies have found an association between higher vitamin K levels and lower incidence of bone fractures. Vitamin K2 has also been linked to prevention of plaque build-up in arteries.Some research suggests that it may play a role in treating rheumatoid arthritis and preventing certain cancers.
Vitamin K2 is found primarily in animal foods, such as chicken, beef, organ meats, egg yolks, and milk, and fermented foods such as hard cheeses and sauerkraut (a cabbage salad native to Germany). It is also produced in the digestive tract by “good” bacteria. The best known source of Vitamin K2 is natto, a Japanese food consisting of fermented soyabeans.
In contrast, vitamin K1(phylloquinone) is obtained from plant foods such as green leafy vegetables, broccoli, Brussels sprouts and asparagus. A small amount of vitamin K1, about 10%, is converted into K2 in your body.
Vitamins K1 and K2 both play a role in blood clotting, so if you are taking warfarin or any other anticoagulant drug, you need to exercise caution when consuming foods that contain vitamin K. People taking these drugs should maintain a fairly consistent intake of vitamin K and inform their prescribing physicians to allow for stable dosing of their anticoagulant medication.