The study’s authors note that, although the associations do not prove causality, the findings raise new questions about the potential neurological effects of the chemical, especially in light of earlier studies that suggest increased prematurity and cardiometabolic health impacts among infants and children exposed to aspartame during pregnancy.

Similarly, another recent study from Florida State University College of Medicine researchers also suggested that aspartame consumption may cause multigenerational spatial learning and memory deficits. The study’s authors urged the U.S. Food and Drug Administration (FDA) to take a closer look at the safety of the chemical.

For the present study, the UT Health San Antonio team asked the mothers of 235 children with autism spectrum disorder (ASD) and of 121 neurotypical children to provide retrospective written estimates of diet beverage and aspartame consumption during pregnancy or breastfeeding. From the written estimates, exposure odds ratios were computed for children with autism, which revealed that males diagnosed with ASD had triple the likelihood of having being exposed to aspartame through their mothers during pregnancy or breastfeeding, when compared to males in the neurotypical control group. The exposure odds were greatest among males with non-regressive autism, also known as early-onset autism.

The researchers call for further studies with larger sample sizes of both sexes and prospective measurement of dietary exposure to aspartame and additional risk factors. In the meantime, the scientists say that pregnant or breastfeeding mothers should exercise caution when consuming diet drinks or other foods and beverages containing aspartame.