The new recommendation is to get at least 400 international units (IU), according to guidelines published by the American Academy of Pediatrics (AAP) in November's edition of Pediatrics.
Some vitamin D experts say the AAP's new vitamin D guidelines don't go far enough.
"I was hoping they'd be more aggressive," says Bruce Hollis, PhD, professor of pediatrics, biochemistry, and molecular biology and director of pediatric nutritional services at the Medical University of South Carolina in Charleston, S.C.
How Much Is Enough?
Greer explains that the AAP used to back the current daily dose recommended by the Institute of Medicine (IOM) but doubled that amount because vitamin D's importance has become clearer in the last five years.
"It's very clear now that, at least in adults, there is some association between insufficient vitamin D and various chronic diseases," including diabetes and rheumatoid arthritis, says Greer. He notes that the research -- mainly done on adults -- doesn't prove that vitamin D prevents those diseases.
Hollis says the new guideline is still too low. "In my estimation, this recommendation just doesn't do much," he tells WebMD.
"I would have probably gone with 400 IU in the first year or two of life, and after that I would have increased it to at least 1,000 and also monitor the vitamin D [blood] level," says Hollis. He questions the AAP's decision to set the same standard for babies as for much bigger adolescents.
Asked about that, Greer says, "we don't have any really good information to say that we should be giving children in the United States more than 400 international units a day," even for adolescents.
The Institute of Medicine, which sets Dietary Reference Intakes for vitamins, hasn't changed its vitamin D recommendations.
"IOM is in discussions with various agencies and other groups that would sponsor a new review by the IOM of the science about vitamin D and calcium intakes to maintain health," IOM spokeswoman Christine Stencel tells WebMD.