From the Guidelines
Vitamin D insufficiency and deficiency are distinguished by different serum 25-hydroxyvitamin D levels, with insufficiency defined as levels between 20-30 ng/mL and deficiency as less than 20 ng/mL, requiring distinct treatment approaches. The differences in vitamin D insufficiency versus deficiency ranges and their respective treatments are based on serum 25-hydroxyvitamin D levels.
- Insufficiency is typically treated with daily supplementation of 1000 IU of vitamin D2 or D3 per day, in addition to the patient's current intake, and rechecking the level in 3 months 1.
- Deficiency, on the other hand, is treated with prescription vitamin D (ergocalciferol) 50,000 IU weekly for 8 weeks, followed by a recheck of the serum 25(OH) D level, with subsequent dosing based on the results 1. It is essential to note that vitamin D toxicity is uncommon but may occur with daily doses of more than 50,000 IU per day that produce 25(OH) D levels larger than 150 ng/mL 1.
- The current expert opinion on supplementation for adults older than age 50 is 1200 mg of calcium (from all sources) and 800 to 1000 IU of vitamin D daily, which is also recommended for younger patients at risk for cancer treatment–associated bone loss 1. Treatment should aim to bring serum 25(OH) D levels to 30 ng/ml (75 nmol/L) or higher, and vitamin D3 could be more effective in raising 25(OH) D concentrations and maintaining those levels for a longer time when longer dosing intervals are employed.
- Patients with malabsorption disorders, kidney or liver disease may need specialized dosing regimens, and treatment should be monitored to avoid excessive supplementation, which can lead to hypercalcemia, kidney stones, or other complications. The goal of treatment is to normalize vitamin D levels, which is crucial for calcium absorption, bone health, immune function, and possibly cardiovascular health.
From the Research
Definition of Vitamin D Insufficiency and Deficiency
- Vitamin D deficiency is defined as a serum 25-hydroxyvitamin D level of less than 20 ng per mL (50 nmol per L) 2
- Vitamin D insufficiency is defined as a serum 25-hydroxyvitamin D level of 20 to 30 ng per mL (50 to 75 nmol per L) 2
- Severe vitamin D deficiency can be defined as the dose of vitamin D or serum 25OHD concentrations needed to prevent nutritional rickets or osteomalacia, with a threshold of 25OHD above 30 nmol/l (12 ng/ml) 3
Treatment of Vitamin D Insufficiency and Deficiency
- The goal of treatment is to normalize vitamin D levels to relieve symptoms and decrease the risk of fractures, falls, and other adverse health outcomes 2
- Treatment may include oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks, followed by maintenance dosages of cholecalciferol (vitamin D3) at 800 to 1,000 IU per day from dietary and supplemental sources 2
- Regimens with >600,000 IU of ergocalciferol given for a mean of 60 +/- 40 days achieved sufficiency in 64% of cases, without vitamin D toxicity 4
- Oral vitamin D3 supplementation of 1,000 IU/day can reduce vitamin D insufficiency by 37% in patients with chronic kidney disease 5
Supplementation Guidelines
- The American Academy of Pediatrics recommends that infants and children receive at least 400 IU per day from diet and supplements to prevent vitamin D deficiency 2
- Evidence shows that vitamin D supplementation of at least 700 to 800 IU per day reduces fracture and fall rates in adults 2
- A daily dose of 800 IU/d and serum 25OHD above 50 nmol/l (20 ng/ml) is considered sufficient by the majority of experts, with a minority opinion aiming for 75 nmol/l or even higher 3