Menaquinone-7

Menaquinone-7 is sold as a supplement to prevent postmenopausal osteoporosis. The evidence is mixed. Knapen 2013 (RCT, 244 women, 3 years, 180 mcg MK-7/day) showed moderate slowing of bone mineral density loss at the femoral neck and lumbar spine. The 2024 Cochrane review did not confirm fracture reduction and rated the evidence as low certainty. First-line treatments for confirmed osteoporosis are bisphosphonates, denosumab and anabolic therapy. If MK-7 was offered as a substitute for proven osteoporosis therapy, consider seeking a second opinion. Important: vitamin K reduces the effect of warfarin and other vitamin K antagonists; patients on these anticoagulants, including those with a mechanical heart valve, must not take vitamin K supplements without medical agreement.

Menaquinone-7 (MK-7) is a form of vitamin K2 marketed as a supplement to slow aging and extend lifespan. So far no convincing benefit for this use has been shown – there is no evidence base for anti-aging or longevity. Lifespan and age-related changes respond more reliably to sleep, physical activity, diet and not smoking; if you have a vitamin K deficiency, talk to a doctor about supplementation. Important: vitamin K reduces the effect of warfarin and other vitamin K antagonists; patients on these anticoagulants, including those with a mechanical heart valve, must not take vitamin K supplements without medical agreement.

MK-7 is marketed as protection against arterial calcification. The idea comes from the Rotterdam Study (J Nutr 2004), an observational analysis of 4807 people showing higher dietary K2 intake associated with less aortic calcification. That is a correlation, not proof. The 2024 Cochrane review could not assess direct cardiovascular endpoints because of the lack of well-powered RCTs. Proven cardiovascular prevention rests on blood pressure control, statins, smoking cessation and physical activity. If MK-7 was offered as a substitute for those measures, consider seeking a second opinion. Important: vitamin K reduces the effect of warfarin and other vitamin K antagonists; patients on these anticoagulants, including those with a mechanical heart valve, must not take vitamin K supplements without medical agreement.