MK-7, or menaquinone-7, is a specific form of vitamin K2, renowned for its significant role in human health, particularly in bone and cardiovascular health. It is distinguished by its long side chain, which consists of seven isoprenoid units, contributing to its unique properties and biological activities.
Sources of MK-7:
MK-7 is predominantly found in fermented foods. Natto, a traditional Japanese food made from fermented soybeans, is an exceptionally rich source of MK-7. Other fermented foods like certain cheeses and fermented dairy products also contain MK-7, but in lower amounts compared to natto.
Absorption and Bioavailability:
MK-7 is notable for its excellent bioavailability and longer half-life in the blood compared to other forms of vitamin K, such as vitamin K1 (phylloquinone) and MK-4. This extended half-life allows MK-7 to be administered in lower doses while still maintaining effective blood levels.
Role in Bone Health:
MK-7 plays a critical role in activating proteins that regulate calcium utilization in the body. It activates osteocalcin, a protein that helps bind calcium to the bone matrix, enhancing bone strength and density. Consequently, adequate intake of MK-7 is associated with improved bone health and a reduced risk of osteoporosis.
Impact on Cardiovascular Health:
MK-7 contributes to cardiovascular health by activating matrix Gla protein (MGP), which inhibits vascular calcification. By preventing the deposition of calcium in the blood vessel walls, MK-7 helps maintain arterial flexibility and reduces the risk of cardiovascular diseases.
Supplementation and Health Benefits:
Given the limited content of MK-7 in Western diets, supplementation can be beneficial, particularly for individuals at risk of bone or cardiovascular diseases. Clinical studies suggest that MK-7 supplements improve bone mineral density and reduce the rate of bone loss in postmenopausal women. They also show potential in reducing arterial stiffness, a marker of cardiovascular risk.
Safety and Recommendations:
MK-7 is generally considered safe, with no significant adverse effects reported at typical dietary and supplemental intakes. However, individuals taking anticoagulant medications should consult with healthcare providers before starting MK-7 supplements, as vitamin K can interact with these medications, affecting their efficacy.
Analyzing MK-7 using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)
Analyzing MK-7 using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) offers high sensitivity and specificity, crucial for detecting and quantifying MK-7 in complex matrices like food or biological samples. This technique separates MK-7 based on its chemical properties, then fragments and identifies it based on its unique mass-to-charge ratios, providing accurate concentration measurements essential for nutritional studies and quality control.