But many health experts (including the Mayo Clinic) recommend at least 1000 ius for those who are D-deficient, and the fact is you may well be one of them.

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The American Academy of Pediatrics says breast-fed infants should get 400 IUs of supplemental D daily.

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However, he said, there's no harm in taking a 200-IU dose of vitamin D because it's difficult to get the recommended daily amount of 600 IUs from food alone for children and adults up to age 70.

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