MK-7 is a form of vitamin K2, which plays a crucial role in blood clotting and bone health. It helps activate proteins that regulate calcium in the body, ensuring that calcium is deposited in bones and teeth rather than in soft tissues, where it could cause harm. This vitamin is primarily found in fermented foods, such as natto, a traditional Japanese dish made from fermented soybeans. MK-7 is also available as a dietary supplement, often marketed for its potential benefits in supporting cardiovascular health and improving bone density.