Most babies should take a daily vitamin D supplement, a new study shows.
That will be a big change for most parents - and even many pediatricians.
Only 1% to 13% of infants under 1 year now get a vitamin D supplement, available in inexpensive drops, according to a study published online today in Pediatrics.
Those drops are needed, the study says, because only 5% to 37% of American infants met the standard for vitamin D set by the American Academy of Pediatrics in 2008: 400 international units a day.
Vitamin D strengthens bone and the immune system and also appears to prevent type 1 diabetes, heart disease and cancer, the paper says.
Few breast-fed babies - 5% to 13%, depending on their age - received the recommended amount of vitamin D, researchers estimated. Although breast milk is the perfect food in every other way, it's often low in vitamin D, says pediatrician Nicolas Stettler, a spokesman for the pediatrics academy who wasn't involved in the study. Because humans originated in equatorial areas with year-round sunshine, babies in the distant past wouldn't have needed to get vitamin D from breast milk, he says.
Yet many formula-fed infants don't get enough, either. Babies need to drink about 32 ounces of fortified formula a day to get 400 international units of vitamin D, says study author Cria Perrine of the Centers for Disease Control and Prevention. Babies younger than 6 months can rarely drink that much. A supplement can give babies all they need.
Many mothers also are vitamin D-deficient.
A second study in Pediatrics reports that 58% of newborns and 36% of mothers were deficient in vitamin D, according to blood tests. Although taking prenatal vitamins helped, more than 30% of moms who took them were still deficient. Getting lots of sunlight helped raise vitamin D levels in moms, but not in their newborns.
The American Academy of Pediatrics recommends babies get no direct sunlight in their first six months, to prevent skin damage and cancer. After 6 months, the academy says, babies should wear sunscreen, hats and protective clothing in the sun.
Relatively few pediatricians today talk about vitamin D with parents, says Wendy Sue Swanson, a pediatrician at Seattle Children's Hospital who wasn't involved in the new research. That may be because the pediatrics academy's previous vitamin D recommendation — 200 international units a day, set in 2003 — was easier to meet, Swanson says.