In recent years, science has begun to better understand the close communication that exists between the gut and the brain. This system is known as the gut-brain axis, a communication network involving the nervous system, the immune system, hormones and the gut microbiota.
In people with Autism Spectrum Disorder (ASD), numerous studies have observed differences in microbiota composition and a higher frequency of digestive symptoms. Although much research remains to be done, these observations open new possibilities for better understanding the condition and improving the quality of life of some patients.
What is the gut microbiota?
The gut microbiota is made up of trillions of microorganisms that live naturally in our intestine.
These microorganisms perform fundamental functions:
- • they help digest certain foods;
- • they produce vitamins and other beneficial substances;
- • they collaborate with the immune system;
- • they take part in regulating inflammation;
- • they produce metabolites that can influence brain function.
Maintaining a diverse and balanced microbiota is an important component of overall health.
What is the relationship between microbiota and ASD?
Research shows that many people with ASD present more frequently with digestive symptoms such as constipation, diarrhea, bloating or abdominal pain.
In addition, some studies have found differences in the composition of the gut microbiota compared with people without ASD.
However, we still don't know whether these changes are a cause, a consequence, or simply a feature associated with the disorder.
What we do know is that the gut-brain axis works in both directions: the brain influences the gut, and the gut can also send signals to the brain through different biological mechanisms.
Can the microbiota be modified?
The microbiota changes throughout life and can be influenced by different factors, including:
- • diet;
- • antibiotic use;
- • sleep;
- • physical activity;
- • stress;
- • certain diseases.
Strategies such as dietary modifications, probiotics, prebiotics and other interventions are currently being investigated to improve gut health in people with ASD.
However, scientific evidence still does not allow for a universal treatment recommendation, and each case must be evaluated individually.
What can we do today?
If a person with ASD presents digestive symptoms, these should be investigated and treated like any other medical problem.
A balanced diet, adapted to individual needs, can help improve overall well-being and support a healthier microbiota.
This approach should always be part of a comprehensive treatment plan, carried out by professionals experienced in both nutrition and ASD.
A takeaway message
The connection between the gut and the brain is one of the most promising fields in medicine today.
Although many questions remain to be answered, research continues to advance and helps us better understand how gut health can influence the well-being of people with ASD.
The goal is not to seek miracle solutions, but to apply strategies based on scientific evidence, adapted to each patient's needs.
Bibliographic references
- • Sharon G, Sampson TR, Geschwind DH, Mazmanian SK. The Central Nervous System and the Gut Microbiome. Cell. 2016.
- • Cryan JF, O'Riordan KJ, Cowan CSM, et al. The Microbiota-Gut-Brain Axis. Physiological Reviews. 2019.
- • Cryan JF, O'Riordan KJ, Sandhu KV, et al. The Gut Microbiome in Neurological Disorders. The Lancet Neurology. 2020.
- • Kang DW, Adams JB, Gregory AC, et al. Microbiota Transfer Therapy Alters Gut Ecosystem and Improves Gastrointestinal and Autism Symptoms. Scientific Reports. 2019.
- • World Gastroenterology Organisation (WGO). Guidelines on Probiotics and Prebiotics.
- • American Gastroenterological Association (AGA). Clinical Practice Guidelines on the Role of Probiotics in Gastrointestinal Disorders.