Vitamin K2 exerts a more powerful influence on bone than does vitamin K1.* Vitamin K2 is a series of molecules known as menaquinones, some of which are found naturally in fermented soybeans. The most common and well studied of the menaquinones is MK-4. Thorne's vitamin K2 is MK-4. Vitamin K2 appears to offer significant benefit for supporting bone health. Although much of the vitamin K2 research has been conducted on postmenopausal support for bones, because vitamin K2 does not have any estrogenic effects, vitamin K2 also offers bone support for other populations, including anorexics, dialysis patients, individuals with Parkinson's disease, those who have cirrhosis of the liver, individuals who have had a bone marrow transplant, those immobilized after a stroke, and individuals on chronic steroid therapy. Thorne's Vitamin K2 Liquid supplies 1 mg of vitamin K2 per drop. Research shows doses up to 15 mg three times daily may be used.