Maternal Iron Intake Linked to Autism Risk

A new study reveals that mothers of children with autism spectrum disorder (ASD) are less likely to have taken iron supplements before and during their pregnancies.

Researchers at the University of California Davis (UCD; USA) and the UCD Mind Institute Clinic (Sacramento, CA, USA) analyzed data from 866 mother-child pairs who were enrolled in the Childhood Autism Risks from Genetics and the Environment (CHARGE) study between 2002 and 2009; of these, 520 were diagnosed with ASD. The researchers recorded frequency and dosages of maternal iron intake during pregnancy and breastfeeding, including from breakfast cereals, vitamins, and other nutritional supplements.

The results showed that there was a five-fold greater risk in children whose mothers had low supplemental iron and other risk factors for delivering a child with ASD. The association between lower maternal iron intake and increased ASD risk was strongest during breastfeeding (after adjustment for folic acid intake). The risk associated with low maternal iron intake was also greater when the mother was older than 35 years and had metabolic conditions during her pregnancy, such as obesity hypertension or diabetes. The study was published on September 22, 2014, in the American Journal of Epidemiology.

“Iron deficiency, and its resultant anemia, is the most common nutrient deficiency, especially during pregnancy, affecting 40 to 50 percent of women and their infants,” said lead author Rebecca Schmidt, PhD, an assistant professor in the UCD department of public health sciences and affiliated with the MIND Institute. “Iron is crucial to early brain development, contributing to neurotransmitter production, myelination, and immune function. All three of these pathways have been associated with autism.”

ASD affects 6 per 1,000 children, and occurs more often among boys than girls. ASD affect three different areas of a child's life: social interaction, communication (both verbal and nonverbal), and behaviors and interests. The three main types of ASD are Asperger's syndrome, pervasive developmental disorder, not otherwise specified (PDD-NOS), and autistic disorder. The DSM-5 also included two rare but severe autistic-like conditions - Rett syndrome and childhood disintegrative disorder.

Related Links:
University of California Davis
UCD Mind Institute Clinic