Constant tummy trouble in children? It could signal autism, says new study

Long-term digestive distress in kids may be linked to autism spectrum disorder, highlighting the need for early screening and tailored care

Imagine a child complaining, not just occasionally of stomach pain or bloating, but persistently over months or years. Most parents might attribute it to diet, infections, stress or an excuse to skip meals. However, new research suggests that there could be a link to autism spectrum disorder (ASD).

 

The study, published in the journal Autism, tracked children over time to map how gastrointestinal (GI) symptoms evolve in those with and without ASD. The findings highlight important intersections between gut health and neurodevelopment, and underline why digestive symptoms in children should not be dismissed too lightly.

 

The study at a glance 

In the study, titled ‘A longitudinal evaluation of gastrointestinal symptoms in children with autism spectrum disorder’, researchers followed 475 children between the ages of 2 and 12, including 322 children with autism and 153 with typical development.  

 

They recorded a range of gastrointestinal complaints like diarrhoea, constipation, abdominal pain, bloating, reflux, at multiple time points. They also examined associations with sleep disturbances, anxiety, and sensory sensitivity. 

The first assessment occurred when the children were between two and four years old. A second assessment took place two years later after the first one, and a final one happened during middle childhood, when the children were between nine and twelve years old.

 

“The gut is often described as the ‘second brain’, and growing research highlights the importance of the gut–brain axis. In children with autism spectrum disorder (ASD), this connection is frequently disrupted. Many autistic children also show a higher incidence of selective eating, preferring foods with specific textures and tastes while avoiding others,” says Dr Ruchi Golash, paediatrician at The Calcutta Medical Research Institute (CMRI). Another behaviour sometimes observed is pica, the consumption of non-nutritive substances such as mud, dirt, or paper, which is far less common in neurotypical children, she says.

 

Key findings of the study

1. Higher prevalence of GI symptoms

Children with autism were found to have nearly double the likelihood of experiencing gastrointestinal issues compared with non-autistic peers. Moreover, many autistic children reported multiple GI problems simultaneously, not just occasional bouts of constipation or bloating, but overlapping symptoms over time.

 

2. Patterns over time

Rather than GI symptoms being transient ‘one-off’ events, the longitudinal design showed that for many autistic children, such difficulties persist or recur across developmental stages. This suggests the gut issues are not merely incidental, but may be intertwined with underlying biology and development.

 

3. Links to sleep and anxiety

Within the autistic group, those with GI symptoms more often reported sleep disturbances, higher anxiety, and sensory sensitivities. This points to possible shared mechanisms influencing both gut and neural systems.

 

“The connection between autism and gut symptoms has not been fully understood. Parents often sense that their child is having digestive issues, but can’t tell what is causing them,” says Bibiana Restrepo, the lead author of the study.

 

“Our research shows that these symptoms are common, persistent, and can affect many areas of a child’s daily life. By identifying and treating them, we may be able to improve both physical comfort and developmental outcomes,” she adds. She is a developmental paediatrician and a professor at the paediatrics department in UC Davis Health (University of California) .

 

Limitations of the study

 

• The information on digestive health relied on parent reports rather than direct medical examinations or lab tests.
• The study was also conducted at a single research centre in California, which means the results may not be generalisable to all populations.
• Some families discontinued their participation over the years.

 

What it means for clinicians

The study adds weight to the idea that gastrointestinal problems should be part of the clinical conversation in autism. It urges clinicians, caregivers and paediatricians to look beyond just diet or infection when GI complaints are recurrent.

 

Don’t ignore digestive complaints 

Children with autism spectrum disorder may sometimes struggle to express why they are feeling uncomfortable, shares Dr Golash. “For instance, they could be experiencing abdominal pain but find it difficult to communicate this. Similarly, they may dislike or feel discomfort with certain foods, textures, or tastes, yet be unable to explain it. This is why caregivers need to be extremely attentive and work closely with qualified paediatricians to design a diet that is tailored to the child’s individual needs,” she says.

 

Holistic, integrated assessment 

Paediatricians, gastroenterologists and developmental specialists should ideally coordinate as managing GI issues in children with ASD presents unique challenges, shares Dr Mukesh Batra, founder and chairman emeritus, Dr Batra’s Healthcare.

“Treating GI problems can significantly improve not only digestive health but also behaviour, mood, and overall quality of life. Interventions like dietary changes, probiotics, and faecal microbiota transplantation (FMT) show promise, though further research is needed. Early autism therapies may also benefit gut health by shaping microbiome composition, diet, and immune function,” he said.

 

Proactive care with AI and genomics

 

While the new study sheds light on the link between gut health and autism, experts say the future of care may lie in harnessing artificial intelligence (AI) and genomics.

The AI based genomic analysis identifies children with variants in genes affecting gut-brain axis communication, immune regulation, and neurotransmitter synthesis, shares Sid Das, co-founder of eGenome.ai, a predictive health technologies firm. 

"Genetic polymorphisms in serotonin transport, inflammatory cytokine production, and microbiome regulation often predict both gastrointestinal dysfunction and neurodevelopmental differences simultaneously. We analyse genetic predispositions to autism spectrum conditions alongside variants affecting intestinal permeability, microbiome diversity, and inflammatory responses, making early intervention possible," he says.

 

A call for further research

The researchers emphasise that recognising and treating digestive issues early could significantly boost a child’s overall well-being, daily functioning, and quality of life. Looking ahead, they note that further studies are needed to uncover the root causes of these gastrointestinal challenges in autistic children and to create more effective strategies for identifying and supporting those most vulnerable to chronic digestive distress.    Also Read: Autism isn't one story, it's thousands. Here's what you need to know 

 

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This report is for informational purposes only and is not a substitute for professional medical advice.