From the Guidelines
The recommended daily vitamin D intake for adults is 600-800 IU (15-20 mcg), with adults over 70 needing the higher amount, while children aged 1-18 should receive 600 IU (15 mcg) daily, and infants under 12 months need 400 IU (10 mcg) as per the guidelines from the ESPGHAN Committee on Nutrition 1.
Key Considerations
- The main function of vitamin D is the regulation of calcium and phosphate, essential for bone health, as noted in the study by the ESPGHAN Committee on Nutrition 1.
- Vitamin D is available in two forms: D2 (ergocalciferol) and D3 (cholecalciferol), with D3 generally considered more effective at raising blood levels.
- The fat-soluble vitamin can be obtained through limited food sources (fatty fish, fortified dairy, egg yolks), supplements, or sun exposure.
- Taking vitamin D with a meal containing some fat improves absorption.
Dosage Guidelines
- Preterm infants on parenteral nutrition (PN) should receive 200-1000 IU/day (or 80-400 IU/kg/day) of vitamin D, term infants up to 12 months of age 400 IU/day (or 40-150 IU/kg/day), and older children 400-600 IU/day, as recommended by the ESPGHAN guidelines 1.
- The Institute of Medicine recommends a total daily vitamin D intake (from all sources) of 400 IU/day for infants and 600 IU/day for children and adolescents 1.
Safety and Toxicity
- While vitamin D toxicity is rare, it's best to avoid exceeding 4,000 IU daily for adults without medical supervision, as excessive supplementation can lead to hypercalcemia and related complications, as noted in the study by the Institute of Medicine 1.
- Prolonged daily intake up to 10,000 IU or up to serum concentrations of 25(OH)D of 240 nmol/L appears to be safe, but serum concentrations >375 nmol/L are associated with acute hypercalcaemia and hyperphosphataemia 1.
From the FDA Drug Label
DIRECTIONS: Take 0ne (1) capsule each week, or as directed by your physician. Take with food. WARNINGS: Vitamin D3 is a high Potency dietary supplement. Do not exceed recommended dosage Not recommended for children, pregnant or lactating women, or individuals with liver disease, and those taking thiazide diuretics may be at greater risk of toxicity.
The recommended vitamin D dosing guideline for adults is to take one capsule (50,000 IU) each week, or as directed by a physician.
- Key Points:
- The label does not provide dosing guidelines for children or infants.
- The product is not recommended for children, pregnant or lactating women, or individuals with liver disease.
- Patients taking thiazide diuretics may be at greater risk of toxicity 2.
From the Research
Vitamin D Dosing Guidelines
The recommended vitamin D dosing guidelines vary by age group. Here are some key points to consider:
- For adults, a daily dose of 2000 international units (IU) (50 µg) of vitamin D3 is recommended to prevent and treat vitamin D deficiency 3.
- The choice of vitamin D compound is important, with cholecalciferol (vitamin D3) being the preferred form for supplementation due to its stability and potency 4.
- For children and infants, the recommended dosing guidelines are less clear, but it is generally recommended to follow the guidelines set by national health organizations.
- A study comparing vitamin D label dosing recommendations to North American national guidelines found that many products recommended doses that were inconsistent with national guidelines 5.
- In older adults, cholecalciferol (vitamin D3) is preferred over ergocalciferol (vitamin D2) for supplementation 6.
- A proposed algorithm for vitamin D dosing suggests testing serum 25-hydroxy-vitamin D (25OH-D) levels before prescribing supplementation, but also provides guidance for cases where testing is not available 7.
Age-Specific Guidelines
Here are some age-specific guidelines for vitamin D dosing:
- Adults: 2000 IU (50 µg) per day 3
- Children and infants: follow national health organization guidelines
- Older adults: cholecalciferol (vitamin D3) preferred over ergocalciferol (vitamin D2) 6
Key Considerations
When considering vitamin D dosing, it is important to: