Moderate evidenceJoints & skin

Bone Support Formulas

Combinations of calcium, vitamin D, vitamin K2 and trace minerals. Calcium plus vitamin D together does modestly reduce fractures; the added minerals and K2 have thinner support, and vitamin D alone does little.

Evidence last reviewed: August 2026

View on iHerb Ships to 180+ countries · welcome discount for new customers

What the science says

Fracture prevention from calcium plus vitamin D Moderate evidence
A 2026 BMJ systematic review and meta-analysis of randomized trials found that combined calcium and vitamin D supplementation reduced total and hip fractures, while vitamin D alone showed no clear fracture benefit. Absolute risk reductions were small and largest in older adults with low intakes or institutional care.
Vitamin K2 (MK-7) and bone loss Limited evidence
A three-year randomized trial in healthy postmenopausal women found that 180 µg/day of MK-7 slowed the age-related decline in bone mineral density at the spine and femoral neck. The effect was modest, the trial was single-centre, and fracture outcomes were not measured.

Dosage & safety

Studied doseTrial-based amounts are roughly 500–1,200 mg/day of elemental calcium (from diet plus supplement) with 800–1,000 IU of vitamin D, and 180 µg/day of MK-7 where K2 is included. Split calcium into doses of 500 mg or less for absorption.

SafetyCalcium supplements can cause constipation and kidney stones, and doses above needs offer no extra benefit; the cardiovascular signal from high-dose calcium remains debated. Vitamin K2 interferes with warfarin and similar vitamin K antagonists — do not take it on those drugs without medical supervision. People with hypercalcaemia, sarcoidosis or kidney disease need medical advice before supplementing.

Scientific references

Calcium, vitamin D, or combined supplementation to prevent fractures and falls: systematic review and meta-analysis
Massé O, Mercurio CM, Dupuis S — BMJ, 2026
Three-year low-dose menaquinone-7 supplementation helps decrease bone loss in healthy postmenopausal women
Knapen MH, Drummen NE, Smit E — Osteoporos Int, 2013

Where to buy

View on iHerb

Ships to 180+ countries · welcome discount for new customers

Referral link — this site may earn a commission on purchases.

Related in Joints & skin

Curcumin (Turmeric extract) Moderate evidence
Collagen Peptides Moderate evidence
Glucosamine Limited evidence
Biotin (Vitamin B7) Limited evidence
MSM (Methylsulfonylmethane) Limited evidence
Chondroitin Sulfate Moderate evidence