The gut brain axis is an important relationship very few people discuss or even understand. It is composed of a two-way communication system between your gut (digestive system) and your brain which constantly send messages to each other. This connection explains why emotions can affect digestion (e.g., “butterflies” in your stomach when anxious) and why gut issues can influence mood and mental health.
The brain can influence gut function through the nervous system (including the vagus nerve), hormones, immune system and metabolites and can affect digestion, appetite, and even the composition of the gut microbiome. These signals can affect behavior, and even the development of certain neurological disorders including neurodegenerative diseases like Alzheimer’s and Parkinson’s disease, psychiatric disorders and neurodevelopmental disorders such as autism spectrum disorder, and mental health conditions like depression and anxiety.
What does all of this mean for the Autism Spectrum (AS) and Intellectually and Developmentally Disabled (IDD) communities?
Gastrointestinal Issues are a common comorbid condition in individuals diagnosed with an Autism Spectrum Disorder (ASD) or Intellectual Developmental Disability (IDD). These issues can significantly impact behavior and overall health which supports the need for more education for individuals, family members and providers, as well as increased individualized comprehensive treatments.
What causes gastrointestinal disorders to be higher in AS and IDD communities than the general population?
Studies show that gastrointestinal disorders like chronic constipation, irritable bowel syndrome (IBS) and other disorders of gut-brain interaction (DGBIs) are strongly influenced by the gut-brain axis. Both ASD and IDD have been linked to immune system abnormalities. Chronic low-grade inflammation in the gut, a common feature in individuals with ASD, can contribute to systemic inflammation and potentially affect brain function and behavior. Certain genetic factors may also predispose individuals to both ASD/IDD and GI disorders. Some studies suggest that shared genetic variants may contribute to the co-occurrence of these conditions.
Individuals with ASD often experience heightened sensory sensitivities, which can impact their eating behaviors and contribute to GI issues. For example, PICA, food selectivity and aversions can lead to nutritional deficiencies and digestive problems. Additionally, certain medications used to manage symptoms of ASD and IDD can have GI side effects.
Mental health
Maladaptive behaviors, such as irritability, social withdrawal, and self-injurious behavior can be associated with GI dysfunction in ASD, while anxiety and stress can exacerbate GI symptoms.
Research Update
Mojdeh Mostafavi, MD, describes gastrointestinal conditions commonly seen in individuals with autism, including Gastroesophageal Reflux Disease (GERD), Inflammatory Bowel Disease (IBD), Eosinophilic GI disease (EGID), Avoidant/Restrictive Food Intake Disorder (ARFID), Disorders of the Gut-Brain Interaction (DGBI), and constipation. She outlines recent research on the prevalence of these conditions in people with autism, emphasizing the complexities of symptom presentation, drivers, and care.
Microbiota-Targeted Interventions in Autism Spectrum Disorder
Interventions aimed at modulating the gut microbiota—including fecal microbiota transplant (FMT), microbiota transfer therapy (MTT), probiotics, prebiotics, synbiotics, antibiotics, antifungals, and dietary strategies—hold promise for improving gastrointestinal health and potentially alleviating neurological symptoms in individuals with autism spectrum disorder (ASD). Among these, MTT has shown particularly encouraging results, demonstrating sustained improvements in both gastrointestinal (GI) symptoms and core features of autism.
Education and Support
Parent to parent, peer support groups, ECHO Model Initiatives and other means to share information with individuals, families and providers who are looking to gain knowledge through lived experiences can help, and a few are listed below. Also, check to see if Family Support Partners are available in your area. If you can’t find a specific organization, check your Local Management Entity/Managed Care Organizations (LME/MCO). If you are not familiar with these entities, start with your local Department of Health and Human Services or any Medicaid service provider.
National and International Resources
Online Support Group for Parents with Special Needs Children
ECHO Model – The ECHO (Extension for Community Healthcare Outcomes) model was developed by Dr. Sanjeev Arora at the University of New Mexico Health Sciences Center, starting in 2003. He was frustrated by the limited access to specialized care, particularly for Hepatitis C patients in New Mexico, and sought a way to extend his expertise to a wider population. This led to the creation of a free, educational model that uses videoconferencing to connect specialists with community providers, enabling them to learn and collaborate on complex cases. More specific Initiatives like ECHO Autism provide training and mentorship to healthcare professionals regarding common and chronic areas of concern can be found here: ECHO Autism Communities
Scientists increasingly emphasize the importance of sharing knowledge about the gut-brain axis with autism spectrum disorder (ASD) and intellectual and developmental disabilities (IDD) communities due to several key findings. Here’s a synthesis of what experts are saying:
Growing scientific consensus underscores the vital role of the gut-brain axis in neurodevelopment, emotional regulation, and behavior—domains directly relevant to autism spectrum disorder (ASD) and intellectual and developmental disabilities (IDD). Experts emphasize that gastrointestinal issues in these populations are not merely peripheral but may be integral to the symptom profile, with implications for diagnosis, intervention, and quality of life. Building knowledge of the gut-brain axis within ASD and IDD communities represents a promising step toward improving symptom management, promoting well-being, and fostering holistic, person-centered care.
About the Author: Jackie Pilgrim is a fellow with The Loreen Arbus Accessibility is Fundamental Program, a fellowship created with Women’s eNews to train women with disabilities as professional journalists so that they may write, research and report on the most crucial issues impacting the disabilities community.