Table 1.

Recommendations for daily intake of vitamin D and treatment for vitamin D deficiency.

Population	The Institute of Medicine’s Recommendations [49]			The Endocrine Society Clinical Practice Guideline on Vitamin D’s Recommendations [8]
	Adequate Intake	Estimated Average Allowance Per Day	Recommended Daily Allowance	Daily Requirement	Upper Limit Per Day	Treatment for Vitamin D Deficiency
0–1 year	400 IUs	-	-	400–1000 IUs	2000 IUs	2000 IU/d or 50,000 IU/wk of vitamin D2 or D3 for at least 6 weeks to achieve serum 25(OH)D >30 ng/mL (75 nmol/L) maintenance therapy of 400–1000 IU/d
1–18 years	-	400 IUs	600 IUs	600–1000 IUs	4000 IUs	2000 IU/d or 50,000 IU/wk of vitamin D2 or D3 for at least 6 weeks to achieve serum 25(OH)D >30 ng/mL (75 nmol/L) maintenance therapy of 600–1000 IU/d
18–70 years	-	400 IUs	600 IUs	600–1000 IUs	10,000 IUs	6000 IU/d or 50,000 IU/wk of vitaminD2 or D3 for 8 weeks to achieve serum 25(OH)D >30 ng/mL (75 nmol/L) maintenance therapy of 1500–2000 IU/d
>70 years	-	400 IUs	800 IUs	1500–2000 IUs	10,000 IUs
Adult patients with abnormal kinetics of vitamin D *	-	-	-	6000–10,000 IUs	10,000 IUs	Dosage should be increased by 2–3 times

* Patients with abnormal kinetics of vitamin D include those with obesity or intestinal malabsorption, or those taking medications that increase the catabolism of vitamin D, including corticosteroids, antiseizures, antiretrovirals, etc.