Feature Summary Natural Factors Vitamin K2 features vitamin K2 as menaquinone-7 (MK-7), an advanced, fat-soluble form of vitamin K that serves multiple functions in the body. The K family consists of a trio of vitamins: K1 (phylloquinone), naturally occurring in leafy green vegetables and plant oils; K2 (mena-quinone) present in butter, cows liver, eggs, certain cheeses and natto, a fermented soybean food; and K3, a synthetic form of the vitamin. K3 has been shown to have toxic effects on the liver and K1 doesn't have adequate benefits for calcium metabolism to dramatically improve osteoporosis or atherosclerosis. Only K2 in the form of MK-7 has been shown to offer 24-hour protection from a single daily dose. Other commercially available subtypes of K2, such as MK-4, only last four to six hours in the body and are required in much larger dosages to be effective. Vitamin K1 is easy to obtain from green leafy vegetables. The bacteria in our intestines will convert some of that to K2, but not enough to prevent or treat atherosclerosis and osteoporosis. K2 is found in the diet in natto, a fermented soybean food popular in Japan, as well as in butter, meat, egg yolks, and organ meats from animals that are fed grass instead of grain. As grass-fed animal products are rare nowadays and a taste for natto is difficult to acquire for most Westerners, a vitamin K2 supplement is the best way to ensure you are getting an optimal daily dose of this important nutrient. Researchers worldwide are only beginning to uncover the many essential roles that vitamin K2 plays in our health. Our growing understanding of this nutrient is rapidly redefining cardiovascular disease as an illness of nutritional deficiency. In addition, a vitamin K2 deficiency appears to be an underlying factor in the development of diabetes and liver cancer. Vitamin K2 also plays an essential role in bone metabolism and promoting healthy teeth. For most people, diet alone will not help them meet their daily requirement of vitamin K2. Daily use of Natural Factors Vitamin K2 makes it easy to get optimum levels of this important nutrient. Safe Vitamin K2 is very safe with no known upper limit or toxic dose. An optimal daily intake of vitamin K has not yet been established. Contraindications Doses of vitamin K2 over 45 mcg daily may negatively interact with oral anticoagulant therapy Patients receiving blood-thinning medications (e.g., Warfarin) should not take vitamin K without consulting a health care practitioner Suggested use 1 capsule daily or as directed by a health care practitioner.