New research -- the first to explore the connection between iron intake and autism rates -- has found that children of women who didn't take iron supplements before and during their pregnancy were significantly more likely to develop autism.
The study, which was carried out by researchers at the UC Davis MIND Institute, found that correlation between low iron intake and autism was strongest -- a five-fold risk increase -- for mothers aged 35 or older at the time of their pregnancy who were either obese or diabetic.
"The association between lower maternal iron intake and increased ASD risk was strongest during breastfeeding, after adjustment for folic acid intake," Rebecca J. Schmidt, study author and assistant professor in UC Davis's Public Health Sciences, said in a press release.
Because iron deficiency is so common in pregnant women, and because the study's findings have yet to be replicated, Schmidt and her colleagues aren't willing to use the research to make new health recommendations to expecting mothers.
"In the meantime the takeaway message for women is do what your doctor recommends," Schmidt added. "Take vitamins throughout pregnancy, and take the recommended daily dosage. If there are side effects, talk to your doctor about how to address them."
And even if the results are replicated, it doesn't solve the mysteries of autism -- some women with high iron intake still had children diagnosed with autism -- but it is one more clue to a complex question with no easy answers.
The study was published this week in American Journal of Epidemiology.