What are the vitamin D targets and typical dosing for older adults with osteoporosis?

• A. Aim for 25(OH)D above 20 ng/mL; commonly 400-800 IU/day.
• B. Aim for 25(OH)D above 30 ng/mL; commonly 800-2000 IU/day; adjust to achieve sufficiency.
• C. Aim for 50 ng/mL; 10000 IU/day.
• D. No supplementation needed.

Answer: (B)

The key idea is maintaining enough vitamin D to support calcium absorption and bone health in older adults with osteoporosis. The best target is a 25(OH)D level above 30 ng/mL. This level helps optimize calcium uptake from the gut and supports bone remodeling, which is crucial for reducing fracture risk in osteoporosis.

Typical dosing to reach that target is commonly 800–2000 IU of vitamin D daily, with adjustments made based on measured 25(OH)D levels until sufficiency is achieved. This approach balances effectiveness with safety, recognizing that many older adults need more than the minimal amounts sometimes suggested for general health.

Higher doses like 10,000 IU daily to push toward 50 ng/mL are not routine for osteoporosis management and carry a greater risk of toxicity if not monitored. Conversely, the option of no supplementation would leave a large risk of deficiency in this population. Aiming for a level above 30 ng/mL with 800–2000 IU/day, tailored by testing, best fits current practice for supporting bone health in older adults with osteoporosis.