During the first six months of life, infants should not get more than 1,000 IU of vitamin D daily, while the daily
dosage of vitamin D
for infants up to 12 months old should not exceed 1,500 IU. The tolerable upper intake level for vitamin D for toddlers younger than 4 years old and young children between 4 and 8 years old are 2,500 IU and 3,000 IU, respectively. Anyone age 9 or older should not get more than 4,000 IU of vitamin D in a day.
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