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• Supports Bone Health by Promoting Carboxylation of Bone Proteins*

• Supports Cardiovascular Health by Affecting Arterial Calcium Deposits*

• Supports Healthy Blood Clotting*


Naturally occurring vitamin K is found as either K1 (phylloquinone), which is derived from food sources such as green leafy vegetables, or K2 (menaquinones). Menaquinones are designated as MK-n, where n denotes the length of the molecule’s aliphatic side chain. Menaquinones are synthesized by bacteria and can be obtained from animal-based and fermented foods. Structural differences between K1 and K2 impact their bioavailability and bioactivity. Furthermore, among menaquinones, menaquinone-7 (MK-7), with its longer side chain, is very hydrophobic. Compared to K1, MK-7’s physiochemical properties make it highly transportable by plasma lipoproteins, increase its extrahepatic (bones, arteries, etc.) availability, and produce its long half-life.[1-3] Absorption of K1 from food can be limited due to its membranebound nature and the individual consumer’s digestive and absorptive variability. Moreover, adequate consumption of foods high in K2 can be challenging. Therefore, dietary supplementation is an important option. In addition, research suggests that higher levels of menaquinones are needed than were previously thought. Supplementary vitamin K can be found in three forms: synthetic K1; MK-4, which is structurally similar to K1; and natural, long-chain MK-7. Biogenetix provides MK-7 as Vitamk7®, a naturally derived and solvent-free vitamin K2 that has been obtained through a patent-granted biofermentation process of Bacillus subtilis natto cultures.* MK-7 Bioavailability Increases Extrahepatic Tissue Utilization Schurgers et al conducted human studies to compare the in vivo properties of orally administered K1 and MK-7. The results supported better bioavailability and utilization of MK-7. Expressed as AUC , MK-7 demonstrated a six-fold better 96 half-life, a seven- to eight-fold higher dose-response level, and a three times higher carboxylated to uncarboxylated osteocalcin ratio (cOC:ucOC†). Furthermore, on a molar basis, MK-7 is a three-to-four times more potent antidote for oral anticoagulation than is K1. Researchers note that, aside from sensitive individuals, “MK-7 supplements containing more than 50 mcg/d may interfere with oral anticoagulant treatment, whereas doses of at least 50 mcg are not likely to affect the INR value in a relevant way.”[2] Nonetheless, practitioners should closely monitor patients taking anticoagulants.* While studies on the absorption and bioavailability of MK-4 at nutritional levels (i.e., doses of 500 mcg/d or lower) suggest less efficacy compared to longer-chain menaquinones at similar doses,[4] this remains subject to debate. It is possible that rapid uptake of MK-4 could account for its observed lack of detection in serum after oral administration,[5] but more studies are needed for clarification.*

D3K2 capsules by Biogenetix