Taking vitamin D supplements appears to be safe for healthy pregnant women, according to a recent study from the Journal of Bone and Mineral Research. In tests on 350 healthy expectant mothers, researchers found that even high doses of vitamin D were safe during pregnancy.
At the start of the study, all participants were 12 to 16 weeks into their pregnancy. Researchers split participants into three groups: one group received 400 IU of vitamin D per day, the second group received 2,000 IU per day, and the third group received 4,000 IU per day. Currently, the recommended vitamin D intake for pregnant women in 600 IU daily.
At the study's end, women who had taken 4,000 IU of vitamin D daily were found to be more likely to achieve and sustain optimal blood levels of vitamin D throughout their pregnancy. What's more, vitamin D caused no adverse effects in any of the women or their newborns. The study's authors note that vitamin D deficiency during pregnancy can negatively affect the immune system and heart health. Although promising, pregnant women should not change their vitamin D intake without consulting their physicians.

