Effect of Calorie Restricted Diet Versus Liraglutide on Intrapancreatic Fat Deposition in People With Obesity: A Pilot Study

OBJECTIVE: This pilot study compared the effects of a calorie restricted diet (CRD) versus liraglutide on intrapancreatic fat deposition (IPFD) in people with obesity and explored associations between changes in adiposity-related metrics and glycemic-related parameters. METHODS: In this 24-week prospective nonrandomized study, participants with obesity received CRD or liraglutide. Primary endpoint was the change in pancreatic fat fraction (PFF). Secondary endpoints included changes in body weight, liver fat fraction (LFF), visceral fat area (VFA), and glycemic-related parameters. RESULTS: Both CRD (n = 23) and liraglutide (n = 23) demonstrated significant and comparable reductions in PFF (time effect: p < 0.001; interaction effect: p = 0.560). Significant and similar improvements were also observed in body weight, LFF, VFA, HbA1c, HOMA2-IR, and ISIM (all time effects: p < 0.001; all interaction effects: p > 0.05). Regression analysis indicated that ΔHOMA2-IR was positively associated with Δweight and ΔLFF but negatively with ΔPFF, while ΔISIM was negatively associated with ΔVFA and positively with ΔPFF. CONCLUSIONS: Both CRD and liraglutide significantly and similarly reduce pancreatic, liver, and visceral fat, while improving glycemic-related parameters in people with obesity. Preliminary findings suggest liver and visceral fat loss primarily drive improved insulin resistance, whereas pancreatic fat reduction may relate to subtler insulin dynamics changes, warranting further investigation. TRIAL REGISTRATION: This study is a sub-study of the registered trial ChiCTR1900022948.