: Obesity is a growing global health concern and a modifiable risk factor for multiple pancreatic diseases, including acute pancreatitis (AP), chronic pancreatitis (CP), and pancreatic cancer (PC). While these conditions have distinct clinical courses, obesity contributes to their pathogenesis through shared mechanisms, such as visceral adiposity, systemic inflammation, insulin resistance, and ectopic pancreatic fat deposition. : This narrative review synthesizes current evidence from clinical, epidemiological, and mechanistic studies exploring the relationship between obesity and pancreatic diseases. We also critically evaluate the effects of weight loss interventions-including lifestyle modifications, pharmacologic therapies, endoscopic approaches, and bariatric surgery-on the risk and progression of disease. : Obesity increases the risk and severity of AP via mechanisms such as gallstone formation, hypertriglyceridemia, and lipotoxicity. In CP, obesity-related intrapancreatic fat and metabolic dysfunction may influence disease progression, although some data suggest a paradoxical protective effect. In PC, obesity accelerates tumorigenesis through chronic inflammation, adipokine imbalance, and activation of oncogenic signaling pathways. Weight loss interventions, particularly bariatric surgery and incretin-based therapies (e.g., GLP-1 receptor agonists and dual agonists such as tirzepatide), show promising effects in reducing disease burden and improving metabolic and inflammatory profiles relevant to pancreatic pathology. : Obesity plays a multifaceted role in the pathophysiology of pancreatic diseases. Therapeutic strategies targeting weight loss may alter disease trajectories, improve outcomes, and reduce cancer risk. Further research is needed to define optimal intervention strategies and to identify and validate biomarkers for personalized risk assessment and prevention.