September 2018

Our Diabetes Center faculty are leaders in diabetes research but occasionally their research leads them to some other areas that are of broad societal interest. This is exemplified by the work of FOEDRC member Dr. Wei Bao MD Ph.D., who is an Assistant Professor in the Department of Epidemiology, of the University of Iowa’s College of Public Health. Dr. Bao’s research is focused on the relationship between diet, food choices and diabetes. Recently Dr. Bao has found an important relationship between certain food allergies and autism. Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder. While surveillance projects have consistently shown an alarming increase in the rate of ASD in US children, the causes of ASD remains unclear. Evidence from animal studies shows that food allergy in mice can induce autistic-like behavioral changes, including reduced social interaction, increased repetitive behavior, and impaired spatial memory. However, little is known on the relation between food allergy and ASD in humans.

In an analysis of a nationwide population-based study involving nearly 200,000 children, Dr. Bao and colleagues reported that children with food allergy are twice more likely to have been diagnosed with ASD. Respiratory allergy and skin allergy are also linked to ASD in this study, but their associations were much smaller in magnitude than the association between food allergy and ASD. Dr. Bao and his colleagues proposed that immune dysfunction may be a shared mechanism for different types of allergic conditions in association with ASD, and additionally, impairment in a gut-brain-behavior axis may link food allergy to ASD. The team acknowledged that this study is observational and does not prove cause and effect. The work was published in the Journal of the American Medical Association (JAMA – Network Open).

In an Invited Commentary accompanying with this research article, Dr. Christopher J. McDougle, the Director of the Lurie Center for Autism at Harvard Medical School, wrote that “To my knowledge, the results [from the present study] are the first to document the association of food allergy with ASD with confidence, in part based on the large sample size [the authors] accessed.” He believes that evidence from the present study in conjunction with previous animal studies underscores the need to define “an immune-mediated subtype of ASD”.