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Vitamin K1 is obtained in the diet primarily from dark leafy vegetables (lettuce, spinach, and broccoli). Unfortunately, vitamin K1 is tightly bound to the chlorophyll in green plants, thus, aging humans are not always able to benefit from ingested K1-containing plants. While vitamin K1 is not absorbed particularly well from food, it is absorbed from supplements, provided that the supplements are taken with meals.

Vitamin K2 (menaquinones) is found in meat, eggs, and dairy products and also made by bacteria in the human gut, which provides a certain amount of the human vitamin K requirement. Human studies show that vitamin K2 is absorbed up to ten times more than K1. Vitamin K2 remains biologically active in the body far longer than K1. For instance, K1 is rapidly cleared by the liver within eight hours, whereas measurable levels of K2 have been detected 72 hours after ingestion.2

Super K provides vitamin K1 and a new biologically active form of vitamin K2 known as menaquinone-2 and menaquinone-7. The menaquinone-7 form of vitamin K is not metabolized quickly by the liver, thereby making it available to provide a more consistent supply of vitamin K to the body.

An abundance of human clinical data reveals that vitamin K plays a critical role in maintaining healthy bone density by facilitating the transport of calcium from the bloodstream into the bone.3,5,6,13,19*  Scientists are getting to understand that vitamin K is also required by calcium-regulating proteins in the arteries. Matrix Glaprotein (MGP) is a vitamin K-dependent protein, and must be carboxylated to function properly; poor vitamin K status results in synthesis of uncarboxylated MGP (ucMGP). Since MGP is a potent local inhibitor of arterial calcification, MGP is important in relation to the health of the entire cardiovascular system. Without adequate vitamin K, calcium in the blood can bind to the arterial wall resulting in calcification. As people age, even a subclinical vitamin K deficiency can pose risks to the vascular system.

The Rotterdam Heart Study, a large-scale, well-controlled clinical trial that tracked 4,800 participants for seven years, revealed that participants who ingested the greatest quantities of vitamin K2 in their diet experienced a better cardiovascular condition than people who ingested the least. High intakes of vitamin K2 also corresponded to less calcium deposition in the aorta, whereas participants who ingested less K2 were more likely to show moderate or severe calcification. Animal studies suggest vitamin K intake not only blocks the progress of further calcium accumulation but also induces 37% regression of preformed arterial calcification.7,8

Those individuals currently taking anticoagulants such as Coumadin® (warfarin) should consult with their personal physician before taking supplemental vitamin K.