“Colorado researchers think they might be able to help veterans with traumatic brain injury and PTSD by improving the health of their gut microbiome,” reported Colorado Public Radio on November 9, 2025.

A University of Colorado School of Medicine study, focused on veterans who experience both brain injury symptoms and severe gastrointestinal distress, has just wrapped up. As Dr. Lisa Brenner, a clinical research psychologist at the Department of Veterans Affairs and the UC School of Medicine, and the lead researcher for this study, says, “One soldier I talked to started talking to me about how in addition to his brain injury symptoms, his guts hurt for several weeks after he was exposed to a blast.”

The research team used Lactobacillus rhamnosus, a specific probiotic strain designed to reduce inflammation and calm the body’s systems. Though full results with not be available until next year, researchers emphasize their focus on scientifically validated – single-strain probiotics rather than over-the-counter multi-strain products, ensuring precise treatment effects for veterans in need.

This targeted OTC approach could decrease TBI symptoms for all brain injury survivors.