The International Scientific Association for Probiotics and Prebiotics has formally defined gut health as "a state of normal gastrointestinal function without active gastrointestinal disease and gut-related symptoms that affect quality of life." This consensus emerges from recognition that the term has become an ill-defined catchphrase across scientific literature, clinical practice, and commercial marketing. The definition encompasses functional, subjective, and extrinsic domains, providing a framework for standardized assessment metrics. This standardization addresses a critical gap that has hampered gut microbiome research for years. Without consistent terminology, studies on probiotics, prebiotics, fermented foods, and dietary interventions have operated under different assumptions about what constitutes gut health, making cross-study comparisons nearly impossible. The consensus represents a foundational shift toward more rigorous research methodology in gastrointestinal science. For consumers, this clarity could improve product claims and clinical recommendations, though the definition's emphasis on subjective quality-of-life measures acknowledges that gut health extends beyond traditional biomarkers. While this is primarily a definitional exercise rather than a novel biological discovery, it establishes essential scientific infrastructure that could accelerate meaningful advances in personalized gut health interventions.