It is no surprise that kids with autism tend to be rather picky eaters, sticking to more or less the same kind of food, or eating in excess the food of their preference. Unfortunately, many kids on the spectrum also frequently encounter various gastrointestinal (GI) problems that seems to exacerbate behaviours of ASD, calling to question if it could be a chicken or an egg issue.
According to a study which examines the association between GI symptoms and maladaptive behaviours , it was reported that parental reports of food allergies, food restrictions, and food dislikes were highest in children with ASD. When measuring the frequency of those maladaptive behaviours and reports of GI symptoms, children with ASD were 3 times more likely to experience frequent GI symptoms  than typically developing children (Chaidez et al., 2014).
In another study using data from the Autism Genetic Resource Exchange, parents reported significantly more GI problems in children with ASD than in their neurotypical siblings, further lending support to the finding that children with ASD are more likely sufferers of GI symptoms as compared to typically developing children. Although the link between ASD behaviour and GI symptoms has not been fully established, it is plausible that continuous pain and discomfort could lead to increased anxiety, irritability and social withdrawal in the child.
Furthermore, the child may display increased stereotypy behavior and hyperactivity as a way to cope with the unpredictable discomfort that accompanies a poorly functioning gut. This is why it is essential for your child to get checked regularly by your doctor for GI problems in ruling out tantrum behaviours that may be caused by intestinal pain and discomfort instead.
Can diet help to regulate uncomfortable GI symptoms?
From several parental reports, it seems that children with ASD display food sensitivities particularly to milk protein and gluten. However a lack of medication has led many parents to adopt the Gluten Free Casein Free (GFCF) diet. This diet, although still considered an alternative treatment, has shown to alleviate some of the GI problems that children with ASD face on a regular basis and subsequently improving their moods as well. Some physicians and nutritionists may also recommend consuming a diet high in omega-3 fatty acids such as salmon, cod liver oil, and other mercury-free supplements to help reduce inflammation in the gut and reduce symptoms of GI.
In another recent study looking at nutritional intake of children with ASD, the lack of fiber has been found to be strongly affecting the upper and lower GI tract that can lead to abdominal pain, bloating, constipation, flatulence, and diarrhea (Ferguson et al., 2019). They also found that many of these children do not meet recommendations for daily intake of fiber, calcium, iron, vitamin E and D, which may be a possible consequence of the GFCF diet. Due to the nature of ASD children preferring routines and showing food selectivity to taste, texture, or temperature, many parents find it hard to ensure their child consumes a well-balanced diet. It is however important to keep track of your child’s nutritional needs according to age, using the Dietary Reference Intake , to ensure a healthy development throughout. Also, keeping a food diary can help you to keep tabs on any food that is potentially causing a bad reaction in your child’s stomach.
Are there any other treatments available?
Yes! New research has recently revealed that kids with ASD lack certain healthy gut bacteria that is essential for maintaining a healthy gut environment, leading researchers to develop treatment that is focused on improving the gut environment from within. This new treatment involves collecting, processing and freezing fecal material of individuals with healthy gut, and administering orally or rectally to introduce the healthy bacteria into the GI tract. The aim here is to tackle GI symptoms at its root by re-establishing a balance in the gut micobiome as a way to improve and alleviate behaviours that might have arisen due to GI problems. The treatment is still currently undergoing clinical trials, and would require more tests to be conducted before it can be approved to be administered to the mass. However, results from the small clinical trial looks promising and may open up a whole new alternative that can possibly alleviate chronic symptoms of GI, and significantly improve the lives of children with ASD.
Written by Marjorie.
 Maladaptive behaviours were measured using the Aberrant Behaviour Checklist (ABC) on five sub domains of irritability, lethargy/social withdrawal, stereotypy, hyperactivity, and inappropriate speech.
 Symptoms include abdominal pain, pain on stooling, constipation, gaseousness/bloating, diarrhea, sensitivity to foods, as well as vomiting and difficulty swallowing