Gastric Emptying in Obesity and Weight‐Loss Interventions: Physiology, Assessment, and Clinical Implications

ABSTRACT

Gastric emptying is a key determinant of digestion, appetite regulation, and metabolic homeostasis. Its assessment relies on several techniques, among which gastric emptying scintigraphy remains the reference standard owing to its physiological relevance and reproducibility when performed using standardized protocols. In current clinical practice, scintigraphy is mainly used for the diagnosis of gastroparesis and dumping syndrome, but in the field of obesity, it appears as a promising research and phenotyping tool. Although earlier studies in obesity reported heterogeneous results, larger cohorts and meta‐analyses now support an acceleration of gastric emptying in subjects with obesity, accompanied by increased gastric accommodation and alterations in gut hormone signaling. Most importantly, obesity treatments, including bariatric surgery, endoscopic bariatric procedures, and pharmacological therapies such as GLP‐1 receptor agonists, induce marked and procedure‐specific modifications in gastric emptying. These changes may contribute to their metabolic and weight‐loss effects. This narrative review summarizes the physiological mechanisms governing gastric emptying, provides an overview of current assessment methods with a focus on scintigraphy, and examines the impact of obesity and obesity treatments on gastric emptying, highlighting its relevance as a potential biomarker and therapeutic target.