In May 2019 researchers from Singapore published their review of the medical scientific literature to assess the effect of prebiotics and probiotics on individuals with autism spectrum disorder. Individuals with this type of disorder frequently have gastrointestinal symptoms and there is some anecdotal evidence that probiotics are able to reduce these as well as improve behavioural issues in children with autism spectrum disorder. A total of 8 studies were included in the review. Two of the studies examined the use of prebiotics and/or diet exclusion while six involved the use of probiotic supplementation in children with autism spectrum disorder. Results showed that prebiotics only improved certain gastrointestinal symptoms. However, when prebiotics were combined with a gluten and casein free exclusion diet there was a significant reduction in anti-sociability scores. As for probiotics, there is limited evidence to support the role of probiotics in reducing the gastrointestinal symptoms or behavioural problems in children with autism spectrum disorder. The researchers concluded by stating that at the current time prebiotics and probiotics have only a limited effect in the management of gastrointestinal symptoms or behavioural problems in children with autism spectrum disorder. However, it was noted that currently there is no standardised regulated course of probiotics, with multiple different strains and concentrations of probiotics being used, as well as variable durations of intake.
Ng QX et al. A Systematic Review of the Role of Prebiotics and Probiotics in Autism Spectrum Disorders. Medicina (Kaunas). 2019 May 10;55(5). pii: E129.