Abdominal Bloating in the Modern Era: Pathophysiological Mechanisms and Environmental Contributors

Over the past decades, abdominal bloating has been recognized as a common gastrointestinal symptom that significantly affects the quality of life of patients and represents one of the most frequently reported manifestations of gastrointestinal disorders. Abdominal bloating has traditionally been considered a symptom with underlying functional causes, including psychological stress, metabolic disorders, and consumption of a Western-type diet. However, none of these factors fully explains its prevalence. It has been hypothesized that the high prevalence of abdominal bloating may be explained by an increased vulnerability of the digestive system, driven by alterations in the function of the intestinal barrier, as well as in neuroendocrine regulation and environmental and metabolic factors. This review incorporates recent insights into intestinal fermentation, dysbiosis, chronic low-grade inflammation, and gut-brain axis dysfunctions to propose a unified conceptual framework. In this context, chronic exposure to emerging environmental factors could reduce gastrointestinal resilience and modulate responses to fermentative and visceral stimuli. Potential environmental factors include air pollution, microplastics, and endocrine-disrupting chemicals. Overall, these findings suggest a potential role for environmental factors in the modulation of gastrointestinal physiology, although direct evidence linking environmental exposure to abdominal bloating in humans remains limited.