A new study published in Science, led by researchers at Rutgers and the University of Granada in collaboration with the Blaser and Manhart labs at CABM, reveals how the gut microbiome shifts from being dominated by competitive interactions in healthy people to being dominated by cross-feeding interactions in people with a wide range of diseases, ranging from IBD to colorectal cancer. The change in these interactions can be quantified by a new metric called the Ecological Network Balance Index (ENBI), which consistently distinguishes healthy from diseased states and even tracks disease progression, offering a path toward robust, noninvasive early warning indicators of disease. The ENBI can be adapted to incorporate additional biological features or the study of specific gut phenomena and be readily applied to other microbiomes (from the vaginal and oral to plant and soil ecosystems), or it can be used for the study and prediction of potential outcomes in therapeutic interventions. By linking microbial ecology with clinical research, this framework advances precision medicine and supports the development of more personalized strategies to maintain or restore gut health. This study also shows how complex properties of microbial communities, beyond mere taxonomic diversity, are important to defining their ecological state. See additional press coverage in Rutgers Today, NPR, The Scientist, Inside Precision Medicine, Bioengineer.org, Medical Xpress, Nutrition Insight, Scienmag, Time.News, and Healthcare in Europe.