Vitamin D3 and K2 are fat-soluble vitamins that play complementary roles in calcium regulation and bone metabolism. Vitamin D3 enhances intestinal calcium absorption and supports immune function, while vitamin K2 directs calcium to bones and teeth and away from soft tissues like arteries. Together, they may reduce the risk of osteoporosis and cardiovascular calcification, particularly in individuals with suboptimal vitamin status.
The formulation uses cholecalciferol (D3), the most bioavailable form of vitamin D, and likely includes menaquinone-7 (MK-7), a long-acting form of K2, although the specific form is not stated. Research suggests that combined supplementation can improve bone mineral density and improve vitamin K-dependent protein activation, especially in postmenopausal women and older adults at risk for deficiency.
Quick Summary
All ingredient amounts are clearly listed with no proprietary blends, allowing full transparency into dosing and formulation.
The vitamin D3 dose is effective for maintaining sufficiency in many individuals, especially when baseline levels are low. However, the K2 dose is significantly below levels used in most clinical trials for bone or cardiovascular outcomes, limiting its standalone efficacy.
Vitamin D3 (cholecalciferol) is the most bioavailable form. The liquid format enhances absorption, especially when taken with fats. The form of K2 is not specified, but assuming MK-7, it would have good bioavailability and long half-life.
The product is safe for most adults at the provided doses. However, vitamin D supplementation requires caution in individuals with sarcoidosis, hyperparathyroidism, or those on certain medications (e.g., corticosteroids, orlistat).
Why Take This Product
Key Benefits
- Supports Bone Health: Vitamin D3 improves calcium absorption, while K2 activates osteocalcin, a protein that binds calcium to the bone matrix. Clinical studies show that combined D3 and K2 supplementation can significantly increase bone mineral density over time [8].
- Promotes Cardiovascular Health: Vitamin K2 helps activate matrix Gla protein (MGP), which inhibits calcium deposition in blood vessels. This may reduce the risk of arterial stiffness and cardiovascular disease, especially when combined with adequate vitamin D levels.
- Enhances Nutrient Synergy: Vitamin D increases calcium absorption, but without sufficient K2, calcium may deposit in soft tissues. K2 ensures proper calcium distribution, making the combination more effective than either nutrient alone for skeletal and vascular health.
Who Should Take This
Potential Side Effects
Ingredient Breakdown
Each ingredient in this formula is selected for its role in calcium metabolism and bone-vascular health. Doses are based on clinical research showing benefits for serum 25(OH)D levels and osteocalcin activation.
Primary Ingredients
Vitamin D3
Enhances calcium absorption, supports immune function and bone health
Adequate per single capsule for maintenance in many individuals, though higher doses may be needed for deficiency correction.
Cholecalciferol (D3) is the preferred form of vitamin D due to superior bioavailability and efficacy in raising serum 25(OH)D levels compared to D2 [1][2]. It is particularly effective in individuals with low baseline levels or higher body weight [3].
Vitamin K2
Activates osteocalcin and matrix Gla protein for bone and cardiovascular health
Need 9-18 servings daily to reach clinical dose range; likely intended as a supportive rather than therapeutic dose.
Vitamin K2 (likely MK-7) acts as a cofactor for carboxylating osteocalcin, improving bone mineralization. While low-dose K1 has improved anticoagulant stability, K2 supplementation at higher doses (e.g., 180 mcg/day) has shown more consistent effects on bone turnover [4][5]. At 10 mcg, this dose supports basic K2 function but is below typical therapeutic ranges.
Practical Recommendations
- Monitor Vitamin Levels: Regular testing of 25(OH)D levels is recommended to ensure levels remain in the sufficient range (30–50 ng/mL), especially with long-term use.
Is it Safe?
The product contains safe, low-dose nutrients when used as directed. However, high-dose vitamin D requires monitoring in susceptible individuals, and vitamin K2 may interact with anticoagulants.
Safety & Considerations
- Drug Interaction: Vitamin D absorption may be reduced by orlistat, cholestyramine, and corticosteroids.
- Medical Condition: Individuals with sarcoidosis, tuberculosis, or hyperparathyroidism are at increased risk of hypercalcemia with vitamin D supplementation.
- Drug Interaction: Vitamin K2 may reduce the effectiveness of warfarin and other vitamin K antagonists; use only under medical supervision.
Reports for Similar Products
The Science
The vitamin D3 dose aligns with evidence-based ranges for maintaining sufficient vitamin D status, especially in deficient individuals. While the K2 dose is modest, it contributes to the carboxylation of bone and vascular proteins when combined with D3.
Shows vitamin D3 is more effective than D2 in raising and maintaining 25(OH)D levels.
Confirms D3 is more effective and durable than D2 in increasing total 25(OH)D, particularly at higher doses.
Demonstrates that 800 IU/day (20 μg) of vitamin D3 improves 25(OH)D levels, especially in those with low baseline or high body mass.
RCT in postmenopausal women showing no significant BMD benefit with MK-7 over 3 years, possibly due to dose or population factors.
Dose-response study showing improved osteocalcin carboxylation with escalating MK-4 doses in postmenopausal women with fractures.
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