Nutrition in autism spectrum disorders: A review of evidences for an emerging central role in aetiology, expression, and management

Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders whose aetiology remains largely unknown, but for which environmental factors appear to be important. Emerging evidences suggest that nutrition may play a major role in the aetiology of ASD; also, specific maternal nutritional-deficiencies appear to be associated with an increased risk in offsprings. In addition, studies are beginning to reveal the beneficial effects of dietary supplementation or restriction in the management of ASD; while at the same time debunking the myths that surround certain purportedly-therapeutic dietary manipulations. In this narrative review (using information from internet databases such as Google scholar, PubMed, Scopus and authoritative texts), we examine the emerging central role of nutrition in relation to aetiology, symptomatology, management, and indices of outcome in ASD; by highlighting available scientific evidences pertaining to the impacts of different dietary manipulations and nutritional supplementation. We also consider the likely future roles of nutrition in ASD, as science continues to grapple with the understanding of a group of neurodevelopmental disorders that are emerging to be largely “nutritional illnesses”.