NAU researcher discovers key to fighting autism may lie not in the mind, but in the gut

Patient with autism spectrum disorder

The Centers for Disease Control and Prevention identifies one in 68 children as having autism spectrum disorder—a number that continues to increase. Though much is known about autism, effective treatments have remained a mystery. That is, until a team, led in part by Northern Arizona University’s Greg Caporaso, showed promising research that could lead to a new treatment option.

The team included collaborators from Arizona State University, Ohio State University and the University of Minnesota. They tested a theory that symptoms of autism could be improved by making the gut microbiome of children with autism more similar to that of neurotypical children. Past research has shown ties between autism symptoms and the composition and diversity of a person’s gut microbes.

To test this theory, the team conducted fecal microbial transplants by taking live gut bacteria from healthy donors and transferring it to recipients with autism.

Eighteen participants with autism who ranged in age from 7 to 16 underwent a 10-week treatment program that involved antibiotics, a bowel cleanse and daily fecal microbial transplants.

The results, which were recently published in the journal Microbiome, were encouraging.

“In this study, we confirmed the previously reported differences between the gut microbiome of children with autism and neurotypical children,” explains Caporaso, director of the Microbiome Center at NAU’s Pathogen and Microbiome Institute. “Additionally, we were able to prove not only that fecal microbiota transplant changes the microbiome in a way that reduces those differences, but that these changes were associated with improvement in gastrointestinal and behavioral symptoms of autism.”

While the long-term impact is unknown, researchers observed an 80 percent improvement of gastrointestinal symptoms associated with autism spectrum disorders, with a 20-25 percent improvement in autism-related behaviors, including improved social skills and better sleeping habits.

Though additional testing is required before an FDA-approved therapy would be available or recommended to the public, the team plans to continue its work.

“In the next phase, we will perform a double-blind, placebo-controlled experiment, which would be the next step toward developing a treatment that could be brought to market,” Caporaso said.

In the meantime, researchers are excited about where this study could go.

“This is very exciting work that illustrates how we can transition from observations relating the gut microbiome and disease toward actions that can be taken to improve human health,” said Rob Knight, director of the Center for Microbiome Innovation at University of California San Diego.

Since a number of components contributed to the study’s success, researchers cautioned families from attempting to replicate the treatment on their own.

“Although we see promise in this treatment, it is important that parents and children consult their physicians,” said Rosy Krajmalnik-Brown, co-lead of the project and associate professor at ASU. “Improper techniques can result in severe gastrointestinal infection.”

The research team included Rosy Krajmalnik-Brown, James Adams and Dae-Wook Kang of Arizona State University and Matthew Sullivan from Ohio State University. The University of Minnesota provided the microbial transplant material. This research was funded through the Arizona Board of Regents, the Autism Research Institute, the National Science Foundation and the Gordon and Betty Moore Foundation. The research team is seeking additional funding to launch a larger clinical trial. For more information on related research projects at NAU, visit or

NAU Communications