Subgroup analysis based on whether or not NAFLD was merged with T2DM showed that SGLT-2 inhibitors significantly reduced body weight in patients with NAFLD in T2DM (SMD = − 2.91; 95% CI [− 3.91, − 1.92]; I2 = 97%; p < 0.0001) compared with that in patients without NAFLD in T2DM (SMD = − 2.25; 95% CI [− 3.08, − 1.43]; I2 = 60%; p < 0.0001; Additional file 1: Fig. S2D and Table S2). The gene discussed is SLC5A2; the disease is type 2 diabetes mellitus.