Recommended Daily Vitamin D Intake for Bone Health

For maintaining optimal bone health, adults should consume 800-1000 IU of vitamin D daily. 1

Recommended Daily Intake by Age Group

Persons 9 to 18 years: 600 IU of vitamin D daily 1
Persons 19 to 50 years: 600 IU of vitamin D daily 1
Persons 51 to 70 years: 600 IU of vitamin D daily 1
Persons 71 years and older: 800 IU of vitamin D daily 1
Adults at risk for bone loss (including those with HIV infection or other conditions affecting bone health): 800-1000 IU of vitamin D daily 1

Serum 25-hydroxyvitamin D [25(OH)D] levels are the best indicator of vitamin D status 1, 2
The target 25(OH)D level for optimal bone health is ≥30 ng/mL (75 nmol/L) 1, 2
Levels below 30 ng/mL are considered vitamin D "insufficiency" and are associated with elevated parathyroid hormone levels and reduced bone mineral density 2
Annual monitoring of 25(OH)D levels is recommended, especially in high-risk populations 2

For maintenance in those with adequate levels: 800-1000 IU of vitamin D daily 1
For mild insufficiency (25(OH)D levels between 20-30 ng/mL): Add 1000 IU of vitamin D3 daily to current intake and recheck in 3 months 1, 2
For deficiency (25(OH)D levels <20 ng/mL): Consider prescription vitamin D2 (ergocalciferol) 50,000 IU weekly for 8-12 weeks, followed by maintenance therapy 1, 2

Vitamin D3 (cholecalciferol) is more bioavailable than vitamin D2 (ergocalciferol) 1
For daily dosing, either form is acceptable 1
For longer dosing intervals, vitamin D3 may be more effective in maintaining 25(OH)D levels 1, 2

Calcium and vitamin D work synergistically for bone health 1, 3
Recommended daily calcium intake:
- Adults under 50 years: 1000 mg 1
- Adults over 50 years: 1200 mg 1
Total calcium intake should include both dietary sources and supplements 1

Vitamin D toxicity is rare but can occur with daily doses exceeding 50,000 IU that produce 25(OH)D levels above 150 ng/mL 1, 2
Very high yearly loading doses (500,000 IU vitamin D3) may increase risk of fractures and falls 1
Vitamin D deficiency may reduce efficacy of bisphosphonates and increase risk of bisphosphonate-related hypocalcemia 1
Vitamin D supplementation not only improves bone mineral density but also reduces the risk of falls, possibly by improving balance 1, 3

Regular weight-bearing exercise (30 minutes at least 3 days per week) 1
Smoking cessation and limitation of alcohol intake 1
Adequate protein intake but moderate in animal protein 4
Consumption of 5 or more servings of fruits and vegetables daily to ensure adequate intake of other bone-supporting nutrients 3, 4