Autism or autism spectrum disorder (ASD) is a complex issue with brain development that can manifest as problems with verbal or nonverbal communication, repetitive behaviors, and difficulty with social interactions. ASD affects over three million people in the United States and has been identified in 1 out of 68 children.
Gastrointestinal disorders are very common in children with autism. In fact, children with autism are 3.5 times more likely to suffer from chronic constipation or chronic diarrhea than their developmentally normal peers. The exact cause of why this happens is not yet completely understood. Some experts have proposed that toxins produced from abnormal gut bacteria may trigger or worsen autism. Parents with children with autism need to have a heightened awareness that digestive issues may be contributing to their child’s discomfort or even behavior regression, especially in children who are non-verbal or have difficulty with expression.
Chronic constipation is the most common gastrointestinal issue in children with autism. In developmentally normal children, chronic constipation usually presents as stool-withholding behavior. However, in children with autism, chronic constipation issues may not be so obvious. Chronic constipation may present as pressing the belly against objects, increased stimming, sluggishness, grinding the teeth, arching the back, or refusal to eat. Causes of chronic constipation may include a diet poor in fiber, slow intestinal motility, anatomical abnormalities, or a sensory issue. Further evaluation by a medical expert may be needed.
Chronic diarrhea in children with autism is not normal and should be further investigated. Bouts of diarrhea in children with autism can be normal, but diarrhea lasting more than two weeks could indicate an intestinal infection, food allergies, malabsorption, immunodeficiency, or an inflammatory condition. Children with autism can have the same reasons to have chronic diarrhea as developmentally normal children, so common causes of chronic diarrhea should always be investigated before looking into rare disorders. Chronic diarrhea may also occur as a result of loose stool coming out around chronically hard stool trapped in the colon.
Gastroesophageal reflux disease and eosinophilic esophagitis can affect children with autism and may be very difficult for a parent to recognize. Children with autism may make odd body postures, try to gag themselves, or even start to refuse to eat. Other children may start to have sleep disturbance if they are having symptoms at night. Some children may have texture issues with feeding or refuse to eat solid food. Such concerns should always be discussed with your child’s doctor.
Many parents with children with autism have reported their child does better on a gluten- or dairy-free diet. This may definitely be true, but there is currently limited data supporting this benefit. It is best to consult with your child’s physician before any special diets are started so proper testing can be done if needed.