Even if it was just meant as a joke, there is actually research in this general area:
The recent finding of the microbiota–gut–brain axis indicates the bidirectional connection between our gut and brain, demonstrating that gut microbiota can influence many neurological disorders such as autism. Most autistic patients suffer from gastrointestinal (GI) symptoms.
Even if it was just meant as a joke, there is actually research in this general area:
https://pmc.ncbi.nlm.nih.gov/articles/PMC9355470/