Comparison of Efficacy of Different Dosages Vitamin K2

Vitamin K is a group name for a number of compounds: K1 is present in chloroplasts in green vegetables, K2 is of microbial origin. Lactic bacteria produce a mixture of higher menaquinones, including menaquinone-7, menaquinone-8, and menaquinone-9. Higher menaquinones not only have very long half-life times (over 3 days rather than 1 hour for vitamin K1); K2 vitamins are also transported to extra hepatic tissues such as bone and vessel wall whereas K1 is preferentially transported to the liver. Nothing is known yet about the efficacy of bacterial K2 vitamins for in vivo K function (carboxylation of essential proteins). This study describes a dose-response experiment for different dosages of bacterial K2 which are compared with one selected dose of K1 and placebo. The efficacy is concluded from the carboxylation of the bone Gla-protein osteocalcin and of the vascular Gla-protein matrix-Gla protein (MGP).

Inclusion criteria

• Healthy men and women between 40 and 60 years old
• Subjects of normal body weight and height according to BMI < 30
• Subjects of Caucasian race
• Subject has given written consent to take part in the study

Exclusion criteria

• Subjects with (a history of) metabolic or gastrointestinal disease
• Subjects presenting chronic degenerative and/or inflammatory disease
• Subjects presenting diabetes mellitus
• Abuse of drugs and/or alcohol
• Subjects receiving corticoϊd treatment including inhalators
• Subjects using oral anticoagulants
• Subjects using vitamin K containing multivitamins or vitamin K supplements