Vitamin D in Pregnancy May Be Key for Baby's Brain
Majority of Women Get Inadequate Amounts of Key Vitamin
Walker says certain groups have a higher risk of missing out on adequate levels of vitamin D. Those groups include women who are overweight or obese, women from lower socioeconomic backgrounds, and women with darker skin.
Geography also plays a role. People from northern states, which don’t get much sun during wintertime, often have lower levels of vitamin D.
“Even here in L.A., where it’s often sunny, people don’t get enough sun, because of smog, because they stay indoors, or because they use a lot of sunblock,” Walker says.
How Much D Is Enough?
Access to vitamin D -- whether through sunlight, food sources, dietary supplements, or a combination -- is not the only issue. It’s not clear how much vitamin D is enough to ensure healthy development, says Morales, who adds that trials are under way to determine just that.
Walker says that prenatal vitamins taken by pregnant women often provide 400 IU (international units) of D. Regardless, there's not enough research yet to say whether supplementing with more vitamin D would help.
“This study shows a relationship, not cause and effect,” says Leonardo Pereira, MD. “Would supplements improve development? We don’t know.”
Pereira, head of maternal-fetal medicine at Oregon Health and Science University in Portland, says this study “supports a role for vitamin D in neurological development, but it is not definitive evidence that should change how we practice.”
Pereira, who was not involved in the study, does not test his pregnant patients for vitamin D deficiency. But if a patient is known to have a deficiency, he will make sure to get them up to adequate levels.
“What will this mean for pregnancy outcomes? Again, we don’t know,” he says.
Walker says that although the study will not change what doctors tell their patients, it should serve as a reminder of the importance of optimizing health and nutrition.
“Being healthy matters for your pregnancy and for how well your child does later on,” she says. “Nutrition is absolutely critical to how well children do.”