Your child needs this vitamin to help her body absorb calcium and build healthy bones. Plus, there's mounting evidence that vitamin D reduces the risk of Type 1 diabetes, multiple sclerosis, and certain cancers. Kids need at least 200 international units a day -- about two eight-ounce glasses of milk. Formula is fortified, but breastfed babies should get liquid supplements starting at 2 months, says Catherine Gordon, M.D., lead researcher of a new study on vitamin D at Children's Hospital Boston.
38: The percentage of babies and toddlers who don't get enough vitamin D