The gut has neurons too: what a new review explains about the microbiota and autism

Many families know it well: weeks of constipation, tummy aches that come out of nowhere, days when going to the bathroom turns into a tense moment. When a child cannot yet explain what is happening, that discomfort often shows up in other ways: irritability, broken sleep, refusing food. For years it was treated as a separate matter. Science is beginning to show that it is not.

What they studied

The review, published in 2026 in Autism Research, the journal of the International Society for Autism Research, brings together what is known about two little-known players. The first is the gut microbiota: the huge community of bacteria that lives in our digestive tract and makes substances that can act on the whole body. The second is the enteric nervous system, a network of neurons inside the wall of the intestine that coordinates its movements and can work on its own, while staying in constant dialogue with the brain through the vagus nerve, whose fibers mostly carry information from the belly upward.

It is signed by researchers from Nantes Université in France, together with Chilean teams from Universidad Andrés Bello and the Millennium Institute on Immunology and Immunotherapy.

What they found

The first finding is a figure many families suspected: according to the studies cited in the review, between 50% and 70% of autistic people have digestive discomfort (diarrhea, bloating, abdominal pain and, above all, constipation), and in childhood these problems appear 4.4 times more often than in neurotypical children.

Several studies also observed that when belly discomfort is greater, some behaviors become more pronounced. For the authors, this suggests that the gut and the brain share part of the underlying mechanisms.

The makeup of the microbiota is often different in autistic people, and some substances produced by those bacteria (short-chain fatty acids, bile acids, tryptophan derivatives) can change how the neurons of the gut work and, with them, the pace of digestion.

But there is no single bacterial “signature” of autism: results vary widely from one study to another depending on age, diet, where people live or how samples are analyzed. One finding caught our attention: a study with children found that the microbiota was only weakly related to behavior and strongly related to a narrow menu, stool consistency and age.

What we still do not know

The review is honest about its limits, and they are worth sharing:

• Much of the evidence on the enteric nervous system comes from mice and zebrafish. To date, no one has directly examined those neurons in tissue samples from autistic people.
• Two things appearing together does not prove that one causes the other: the link between bacteria, digestion and behavior is still an open hypothesis.
• Some trials of fecal microbiota transplantation, an experimental medical procedure, reported improvements, but they were small and lacked placebo comparison groups. The authors call for larger studies before drawing conclusions.

In other words, this is a promising line of research, not a recipe. Nothing it describes justifies changing a child’s diet or giving supplements or probiotics without guidance from a health team.

What we can take home

While science moves forward, some things are already in the family’s hands and do not need to wait for results:

1. Observe and keep a record. For two weeks, note meals, bathroom visits, sleep and moments of irritability. A simple log helps you spot patterns and gives your pediatrician valuable information.
2. Name what happens inside the body. Recognizing internal signals (hunger, needing to pee, pain) is a skill that can be learned, called interoception. A drawing of the body, picture cards or the question “where do you feel it?” give your child tools to let you know before discomfort turns into a crisis.
3. The table, without pressure. The review links a narrow menu to differences in the microbiota. Exploring new flavors calmly (touching them, smelling them, sharing them as a family), without forcing, is a respectful way to gradually broaden what your child eats.

The next step: meet your child at their developmental stage with TAEO | EdTech

This review confirms something that has guided our work for years: an autistic child’s path is not shaped by the brain alone, but by the whole body and by what they live every day. Meals, bathroom time and rest belong to the Sensory and Independence areas, two of the eight aspects of neurodevelopment that the app supports.

Its pages hold another lesson: there is no single bacterial profile, because every person is different. We see the same at home: two autistic children may need very different support. That is why TAEO | EdTech does not start from a label but from what your child already does: the Skills and Competencies Profile places their real developmental level and, from there, the platform organizes daily activities to practice in the routines you share.

The science of the gut still has open questions; everyday life, however, does not wait. There, a family that observes, understands and supports with calm makes a real difference. At the TAEO Psychoeducational Organization we have poured more than sixteen years of experience into TAEO | EdTech so those moments become learning opportunities, with a human team guiding you step by step.

For our official launch in December 2026, you can request an invitation to the free trial using the form below.