High adherence to a healthy prenatal dietary pattern is associated with a lower likelihood of autism diagnosis in offspring, according to a study published online on July 18 in JAMA Network Open.

The research, led by Dr. Catherine Friel from the University of Glasgow, utilized data from two major birth cohort studies: the Norwegian Mother, Father, and Child Cohort Study (MoBa) and the Avon Longitudinal Study of Parents and Children (ALSPAC). The study aimed to investigate how prenatal dietary patterns relate to autism diagnosis and associated traits.

The analysis included data from 84,548 pregnancies in MoBa and 11,760 pregnancies in ALSPAC. The findings revealed that high adherence to a healthy dietary pattern during pregnancy was linked to reduced odds of an autism diagnosis in adjusted models (odds ratio, 0.78). Additionally, a healthy diet was associated with fewer social communication difficulties at age 3 in MoBa and at age 8 in ALSPAC (odds ratios, 0.76 and 0.74, respectively). However, the study did not find consistent associations with other autism-related outcomes.

The authors acknowledge the need for further research to establish causality, noting that the current findings contrast with previous literature and the variability in autism-associated traits measured. "At present, we remain uncertain as to whether the associations observed are causal," they write, emphasizing the importance of additional studies to confirm these results.