Vitamin K2 + D3, 60 Tablets
Source Naturals Vitamin K2 + D3 combines menaquinone-7 (MK-7), a long-acting form of K2 derived from fermentation, with cholecalciferol (D3) to support calcium metabolism, bone density maintenance, and cardiovascular health.
May be a fit for
- Adults seeking K2 to support calcium routing to bones
- Those using D3 who want complementary K2 co-factor support
- Individuals supporting bone mineral density with K2 and D3 together
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Source Naturals Vitamin K2 + D3 combines menaquinone-7 (MK-7), a long-acting form of K2 derived from fermentation, with cholecalciferol (D3) to support calcium metabolism, bone density maintenance, and cardiovascular health. This pairing is designed for adults seeking to optimize how calcium is directed in the body, toward bones rather than soft tissues.
Why It's Worth Considering: MK-7 offers a longer half-life than MK-4, making it a well-regarded choice for sustained K2 activity, and pairing it with D3 reflects how these two nutrients work synergistically in calcium regulation.
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Product details
Who it may suit
May be a fit for
- Adults seeking K2 to support calcium routing to bones
- Those using D3 who want complementary K2 co-factor support
- Individuals supporting bone mineral density with K2 and D3 together
- Older adults maintaining cardiovascular and skeletal health with vitamin K2
Considerations
- Taking warfarin/Coumadin (K2 counteracts warfarin — consult physician)
- Other vitamin K-dependent anticoagulants
- Note: K2 does NOT interact with non-vitamin-K blood thinners like Eliquis or Xarelto
Compatibility & interactions
Works Well With
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Take Separately From
No significant interactions identified. Always consult your healthcare provider.
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Strong consensus that K2+D3 offers significant cardiovascular and bone benefits, though rare side effects like palpitations and calcium concerns warrant caution.
This summary includes broader brand discussion. Individual experiences are not evidence of product effectiveness.
A few useful answers.
Research & further reading
More category questions
What is the difference between K1 and K2?
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.
What is MK-7 and why is it the preferred form?
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.
How much vitamin K2 should I take?
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.
Can I take K2 if I'm on blood thinners?
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.
Supplement information is provided for education and is not a substitute for personalized medical advice. Supplements are not intended to diagnose, treat, cure or prevent disease. Read the current product label before use.