Some natural sources of vitamin K2 are fermented soy foods, beef, chicken, organ meats and dairy products that have a high fat content. However, food sources with the highest amounts of vitamin K2 are grass-fed animals, as noted by Today's Dietitian.
Vitamin K2 is a fat-soluble vitamin, which is also called menaquinone, as noted by World's Healthiest Foods. In the vitamin K family, both K1 and K2 play essential roles in blood coagulation. Although most people can get adequate amounts of vitamins K1 and K2 from food sources, a deficiency in these vitamins can lead to bleeding issues.
Vitamin K2 is especially important for bone and heart health, as stated by Today's Dietitian. For this reason, it is necessary to get adequate amounts of vitamin K2 through diet. Natural sources that contain this vitamin are meats, poultry, liver, butter, ham, egg yolks, whole milk and cheese. For example, 1 cup of both beef liver and dark meat turkey contain approximately 5 micrograms each of vitamin K2.
When compared with food by-products that come from grain-fed animals, food products from grass-fed animals may contain higher levels of K2 because animals can convert vitamin K1 found in grass into K2. Additionally, fermented soy products, such as natto and miso, are good sources of this nutrient. There are 1,000 micrograms of vitamin K2 in 3.5 ounces of natto and between 10 and 30 micrograms in miso.