Jarrow Formulas enjoys broad brand trust across product lines, though reviews rarely address MK-7 specifically.
Jarrow Formulas MK-7 delivers 90 mcg of menaquinone-7, the long-chain form of vitamin K2 derived from natto fermentation, in a softgel format designed to support calcium utilization, bone matrix formation, and cardiovascular health. MK-7 is favored over shorter-chain K2 forms for its extended half-life in circulation, meaning a single daily dose may help maintain active K2 levels throughout the day. This product is suited for adults focused on skeletal integrity and arterial health, particularly those already supplementing with vitamin D3.
Why It's Worth Considering: The 90 mcg dose reflects a clinically studied range for MK-7, and the natto-derived sourcing aligns with the form most researched for bioavailability and durability in the body.
Vitamin K1 (phylloquinone) is for blood clotting — abundant in leafy greens. Vitamin K2 (menaquinone) directs calcium metabolism — puts calcium in bones and keeps it out of arteries. Most people get enough K1 from diet but are deficient in K2, which is found mainly in fermented foods (natto, certain cheeses) and animal liver.
MK-7 is the most bioavailable and longest-acting form of K2, with a half-life of ~3 days (vs ~1 hour for MK-4). This means a single daily dose maintains therapeutic blood levels 24/7. MK-7 is derived from natto (fermented soybeans) and has the strongest clinical evidence for bone density and arterial health.
For general health with D3: 100-200mcg MK-7 daily. For osteoporosis: 180-360mcg. For cardiovascular calcification prevention: 180-200mcg. The dose should scale with your D3 intake — higher D3 doses require more K2 to handle the increased calcium absorption.
If you're on warfarin/Coumadin: NO — K2 counteracts warfarin and will destabilize your INR. Consult your cardiologist. If you're on newer anticoagulants (Eliquis/apixaban, Xarelto/rivaroxaban, Pradaxa/dabigatran): these are NOT vitamin K-dependent, so K2 is safe. Always confirm with your prescribing physician.
Ask Gabriel for personalized stacking recommendations.
No significant interactions identified. Always consult your healthcare provider.
† These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
