Emerging neurobiological research is investigating the link between the Gut-Brain Axis and Autism Spectrum Disorder (ASD), commonly known as autism. Autism is a complex neurodevelopmental disorder. It affects every child differently, and its co-occurring gastrointestinal symptoms can be challenging for parents, professionals, and patients alike to manage.
Research has suggested that the Gut-Brain Axis may play a role in the symptoms Autistic people experience. Understanding this linkage may shed insight into how patients can better manage their symptoms and find comfort through gut health. We’ll cover a birds-eye view of this linkage, and how it can potentially be leveraged to help people with autism.
The Autism Self Advocacy Network defines autism as a developmental condition that affects how some people experience the world around them. The collective term for autism, ASD, also includes others categorized within the spectrum.
Most commonly, autism can affect how people think, communicate, and interact with others. However, it’s important to recognize that every autistic person experiences autism differently. Estimates put that 1 in 54 children are affected by the invisible condition. The last time the CDC accessed the frequency of children with autism spectrum disorder was from birth year 2016.
There are many co-occurring pathologies typical in people with ASD, including but not limited to certain gut connection conditions such as gastrointestinal (GI) symptoms, increased “leakiness” of the cells that line your intestinal tract, and dysbiosis. Dysbiosis is an imbalance of the gut microbiome that favors bad microbes over beneficial ones, including Clostridioides species.
Not only are GI-related symptoms more common in ASD, but they are known to correlate with the intensity of the condition. This association between autism and the gut brain axis suggests that the gut brain axis may be linked to autism. But what exactly is the gut brain axis, and how could this be?
The Gut-Brain Axis
Our bodies are magnificent machines—every second, the human body produces around 3.8 million cells. To put the magnitude of this into perspective, it only takes about 90 seconds for our bodies to produce as many cells as the entire population of the United States. That’s a lot of moving pieces. Not to mentionthe better half of the cells in our bodies that aren’t even ours that comprise our microbial ecosystem.
The Gut-Brain Axis is a complex network of connections between the central nervous system and the trillions of bacteria that live in the digestive system. This association between the gut microbiome and the brain is complex and a research field teeming with discoveries. Research using germ-free mice (mice raised without any exposure to microorganisms) has provided the bulk of the most compelling evidence for the association. Scientists have linked the Gut-Brain-Axis to the following critical parameters for human behavior:
cognitive functions, including learning capacity and memory
mood and emotion
temperament and character
social interaction and reproductive behavior
More relevant to autism research, one landmark study demonstrated that germ-free mice that received transplants of gut microbiota from autistic people exhibited behaviors associated with ASD. These mice also displayed certain gene-expression patterns (alternative splicing) that align with those common in autistic people. The Gut-Brain Axis has accordingly been linked to ASD, largely based on the correlative associations drawn from the bulk of GI abnormalities that present discomfort to many autistic people and studies with germ-free animal models.
This important development suggests that autistic people may benefit from therapeutics that target the gut microbiome and attenuate the GI symptoms that often accompany the condition.
Towards this end, Sun Genomics has teamed up with Arizona State University’s Autism/Asperger’s Research Program and the Biodesign Institute to uncover more about the potential connection between autism and the gut microbiome and how custom probiotics can help. You can read more about this project here.