Called "Activator X" by Dr. Weston Price, Vitamin K2 is a fat soluble vitamin that supports healthy dental, bone, heart, nerve and brain health. It also supports healthy aging and energy production in the cell. K2 in the MK-7 form is largely missing in the modern diet due to the absence of traditional animal foods, especially aged cheeses. Purely K contains an optimal dose of K2 to support every tissue in the body. One of the primary roles of Vitamin K2 is to regulate calcium and guide it out of soft tissues like arteries to bones and teeth, where it should be.  PURELY K is a synergistic blend of three forms of Vitamin K:  K1 or Phytomenadione K2 in MK-4 form called Menaquinone-4 K2 in MK-7 form called Menaquinone-7 Each one has their strengths and weaknesses. Most vitamin K supplements will contain only K2, only in the MK-7 form, or in too small of amounts to have a substantial effect on the body.  K1, or Phytomenadione, activates proteins in your blood that allow clots to form. When you see the green color in plants, you're seeing phytomenadione. It acts in plants like COQ10 does in humans to allow them to produce energy. It has a similar structure to ubiquinone.  The RDA for K1 is 120 mcg for men and 90 mcg for women. We all know that the Recommended Daily Allowance (RDA) levels are set ridiculously low to support life but not robust health. One capsule of Purely K contains 1000 mcg of K1. K1 is especially important if one is on an animal-based diet and restricting vegetable consumption, which may be a good idea anyway with the rampant NPK fertilizer and tap water use. There is a very small amount in fruit but K1 is mainly present in green vegetables.  While the body can recycle K1 and dietary deficiency is rare, conditions such as intestinal malabsorption or liver disease can inhibit the recycling process. Prolonged bleeding, nose bleeds, easy bruising bleeding gums and heavy menstrual periods are all symptoms of a K1 deficiency.  Vitamin K1, sourced from evening primrose, is primarily included to support healthy blood clotting, which is useful if one is taking systemic enzymes or aspirin therapeutically. Both of those substances thin the blood so K1 from a good source is helpful to balance them.  MK-4 is the form of K2 that we naturally receive from animal foods, namely grass-fed beef, butter and pastured egg yolks. The organ meat liver contains the highest source of MK-4.  Purely K contains 2000 micrograms per serving. The amount used therapeutically in clinical studies is 4500 micrograms. If you consume a balanced diet that includes high quality animal foods, plus take two Purely K daily, it is easy to reach this number. Mammals can synthesize MK-4 from K-1.  Intake of MK-4 has shown to be neuroprotective and help reduce the risk of prostate cancer. Interstingly, MK-4 can also act as a pseudo-CoQ10 molecule. Helping with electron transport in the mitochondria and ultimately making energy for us! MK-7 is the star of the show in Purely K. Exclusively found in fermented soy, or natto, and aged cheese, this crucial nutrient is severely deficient in the majority of the western population.  While its primary role is to activate osteocalcin and matrix GLA protein to regulate calcium throughout your body, its benefits extend far beyond that. Dramatically reducing your risk for arthritis, osteoporosis and atherosclerosis is just the beginning!  K2 MK-7 has been shown to prevent and reverse arterial blockages, prevent heart attacks, increase bone density, prevent diabetes, reduce insulin production, reduce the risk of Alzheimer's disease, prevent wrinkles, prevent varicose veins, and even increase energy production in the cells. Vitamin K1 and K2 MK-4 have a shorter half life than K2 MK-7, meaning that with K2 MK-7, taking it on a regular basis will yield the best results.