What did clinical studies of microbiota transfer therapy report for people with autism spectrum disorder?

In clinical studies, microbiota transfer therapy—a procedure involving the transfer of fecal bacteria from healthy donors into the gastrointestinal tracts of individuals with autism spectrum disorder—has been associated with positive outcomes. Specifically, these studies reported improvements in both gastrointestinal health and behavioral symptoms among patients.1

While these findings are of interest, it is important to note that the procedure, often referred to as fecal microbiota transplant (FMT), carries potential risks, including the transmission of undetected pathogens. Furthermore, while FMT is an established treatment for recurrent Clostridioides difficile infections, its use for other conditions remains an area of ongoing investigation, and researchers continue to study the complex ways in which transplanted microorganisms may influence gut environments and behavior.23