Gut Microbes and Autism

In a 2023 report, a multi-institutional group of American scientists reported new evidence regarding the linkage between the microbiome and autism. The powerful effects bacteria living inside your colon may have upon your brain function has been long  known and well described. Doctors refer to this biological interplay as the gut-brain axis. 

In the recent study, scientists evaluated more than seventy medical publications comprising more than five hundred people. They determined the bacterial population in the gastrointestinal tracts of those affected by autism was distinct from neurotypical individuals. The particular microbes significantly more likely to be present in the guts of autistic individuals belonged to the families of Prevotella, Bifidobacterium, Desulfovibrio and Bacteroides. In other words, the scientists discovered those with autism had different types of bacteria in their colons when compared to neurotypical individuals. 

Scientists believe aberrant gut bacteria may emit inflammatory cytokines which cross the blood-brain barrier and (via epigenetic mechanisms) alter the expression of genes in the brain. In other words, autistic people’s gut bacteria may send signals to the brain which activate (or deactivate) genes and produce brain proteins which alter mental functions.

What can be done about it?

It’s too early to say whether changing the population of the microbiome (gut bacteria) would alter the clinical outcomes of autistic people. Even if one wanted to do so, changing the microbiome (comprising trillions of bacteria) is no mean feat. But the technology of fecal transplantation does make such alterations possible. If you’d like to explore the topic further… https://brain2mind.substack.com/p/building-a-better-brain-from-the