Does having different gut bacteria affect children with Autism Spectrum Disorder and ADHD?

Research shows that children with Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) often have different gut bacteria compared to neurotypical children. These differences may play a role in both gut and behavioral symptoms. While the exact cause-and-effect relationship is still being studied, the gut-brain connection appears important in these conditions.

What the research says

Multiple studies have found that children with ASD and ADHD have distinct gut microbiota compositions. A 2023 study showed that children with ASD, ADHD, or both had gut bacteria profiles that were very similar to each other but different from unrelated healthy children ¹⁰. This suggests a shared microbial signature across these neurodevelopmental disorders. Another review noted that ASD children often have increased Firmicutes and decreased Bacteroidetes, with a lower Bacteroidetes-to-Firmicutes ratio linked to behavioral and gastrointestinal issues ⁹. The same review found that probiotics, especially Lactobacillus and Bifidobacterium strains, showed promise in improving symptoms in 66% of studies ⁹. Additionally, a 2021 study found differences in plasma and fecal metabolites in ASD children, including altered amino acid and lipid profiles, which correlated with clinical behavior scores ¹¹. These findings support the idea that gut bacteria and their metabolic products can influence brain function and behavior.

What to ask your doctor

• Could my child's gut bacteria be affecting their ASD or ADHD symptoms?
• Are there any tests to check for gut microbiome imbalances in my child?
• Would probiotics or dietary changes be a safe option to consider?
• How can I tell if my child has gastrointestinal issues related to their condition?
• Are there any ongoing studies or treatments targeting the gut-brain axis for ASD or ADHD?