A potential link between vitamin D and autism has been suspected for some time now. One study found that children with autism had significantly lower levels of vitamin D than children who did not have autism, and another small study suggested that vitamin D supplementation could assist in improving some of autism’s “core symptoms.” Newly published research in Molecular Psychiatry suggests that the link may begin very early indeed: a study involving more than 4,200 children and their mothers in the Netherlands found that women who were vitamin D deficient at 20 weeks pregnant were more likely to have a child with autistic “traits” at the age of six years-old. Low levels of vitamin D in pregnancy are common as is vitamin D deficiency in general. Between 40% and 60% of women in the United States are vitamin D deficient. Pediatricians and family doctors generally urge liquid vitamin D supplementation for all infants within the first few days of life to boost and maintain baby’s vitamin D stores, but this study may also encourage doctors to push vitamin D for pregnant women too. Although the study’s authors urge further research for determining more about the causality of this link, they note that Vitamin D supplements are widely available, inexpensive, and could be helpful in reducing rates of autism spectrum disorder and related traits. Supplementation with vitamin D could be beneficial in more ways than one for pregnant women and new moms since vitamin D deficiency has been linked to symptoms including fatigue, joint pain, and depression.