FORMERLY MAXIMUM VITAMIN D3+K2

Direct calcium

Name: D3+K2 Cofactor Complex
Brand: Neurobiologix
SKU: NBXA978
Price: 40.50 USD
Availability: InStock

to the bones.

Vitamin D3 raises blood calcium. Vitamin K2 decides where it goes. Without K2, calcium drifts into arteries instead of bone. This formula pairs 10,000 IU of D3 with patented vitaMK7 and the trace cofactors VDR receptors need.

Shop D3+K2 Cofactor Complex View Formula →

Purchases are completed at Neurobiologix, the seller. Gene Direct Nutrition may earn a commission.

PROFESSIONAL GRADE · 60 CAPSULES · D3 10,000 IU · K2 MK-7 · ZINC · BORON

POTENCY

10,000 IU Vitamin D3

Clinical-dose cholecalciferol.

Cholecalciferol is the form the body makes in response to sunlight. At 10,000 IU, this is the therapeutic range many practitioners use to restore serum 25(OH)D in genuinely deficient patients.

TRAFFIC CONTROL

45 mcg vitaMK7 K2 MK-7

Calcium to bone, not artery.

vitaMK7 is a patented, natural menaquinone-7 that activates osteocalcin and matrix-Gla protein — the proteins that shuttle calcium into bone and out of soft tissue. This is the missing co-pilot for high-dose D3.

VDR SUPPORT

4 synergistic cofactors

Built for VDR variants.

VDR Taq polymorphisms can blunt the body's response to vitamin D. Zinc, boron, and K2 support receptor function and calcium partitioning — the chemistry behind real-world utilization, not just blood levels.

MAY BENEFIT

Calcium needs
a traffic director.

Bone density

K2 activates osteocalcin to bind calcium to bone matrix — the molecular basis of skeletal strength.

Cardiovascular support

Matrix-Gla protein keeps calcium out of vessel walls, supporting healthy arterial flexibility.

Immune resilience

Vitamin D receptors on immune cells regulate antiviral and anti-inflammatory gene expression.

Inflammation balance

Adequate D3 status supports healthy cytokine signaling and inflammatory resolution.

Calcium utilization

Boron and zinc support the enzymatic chemistry that allows calcium to reach the right tissues.

MTHFR/VDR optimization

Cofactor-dense design supports patients whose genetic variants blunt D3 activity.

Formula

Four ingredients. One coordinated pathway.

KEY INGREDIENTS

Vitamin D3

Cholecalciferol · 10,000 IU · 250 mcg · 1250% DV

Zinc

as Zinc Picolinate · 4 mg · 36% DV

Boron

as Boron Citrate · 15 mg

Menaquinone-7 (Vitamin K2)

45 mcg

OTHER INGREDIENTS

Hypromellose (Capsule), Silicon Dioxide, Microcrystalline Cellulose, Ascorbyl Palmitate.

DIRECTIONS

Adults: Take one capsule daily with a meal or as directed by a healthcare practitioner.

MAY BENEFIT:

Bone & Joint Health

Cardiovascular Health

Energy

Immune System

Renal Health

Allergy

Questions

Frequently asked.

Why do I need K2 with high-dose D3?

Vitamin D3 raises calcium absorption from the gut and mobilizes it from storage. K2 activates the proteins — osteocalcin and matrix-Gla protein — that tell calcium where to go. Without K2, there is credible research suggesting high-dose D can contribute to soft-tissue calcification. The two vitamins are designed to work together, not alone.

Is 10,000 IU safe to take daily?

For adults with documented deficiency or practitioner-identified need, yes — many functional and integrative clinicians use this dose routinely. For otherwise replete adults, daily 10,000 IU may be more than required. Ask your practitioner about serum 25(OH)D testing to personalize the dose.

What makes vitaMK7 different from other K2 products?

vitaMK7 is a patented, natural, fermentation-derived MK-7 with published stability and bioavailability data. The MK-7 form has a longer half-life than MK-4, allowing once-daily dosing to maintain steady activation of calcium-binding proteins.

Can I take this with blood thinners?

If you take warfarin or other vitamin K-sensitive anticoagulants, consult your practitioner before starting. Vitamin K can affect INR values, and dose adjustments or monitoring may be needed. Most direct-acting oral anticoagulants are not vitamin-K dependent.

Who should take this formula?

Adults with documented vitamin D insufficiency, VDR Taq polymorphisms, bone density concerns, or who want cardiovascular-smart D3 supplementation. Pregnant or lactating women and children should consult a healthcare practitioner before use.

When should I take it?

One capsule daily with a meal that contains fat — both D3 and K2 are fat-soluble and absorb substantially better alongside dietary fat. Morning or midday is typical; late-evening dosing may be activating for sensitive individuals.

The Science

Learn the why.

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