In Massachusetts, new research shows that common dairy products could be a good source of dietary vitamin K, which helps the blood to clot, and is most commonly thought to come from leafy greens such as spinach, kale and broccoli. Tufts University scientists quantified the activity of two natural forms of vitamin K in dairy products including milks, yogurts and cheeses.
Dietary sources of vitamin K are found in two natural forms: phylloquinone or PK, which is widely distributed through plant-based foods, and menaquinones or MK, which appear to be primarily in animal products and fermented foods. Almost all MK forms are also produced by bacteria in the human gut.
Additional research is needed to determine the role of microbes used in production of dairy products and their impact on MK content. Given their abundance in the U.S. diet, researchers need to determine the relative bioavailability of all MK forms.