Context In 2020, the terminology of metabolic dysfunction-associated fatty liver disease (MAFLD) was proposed to replace non-alcoholic fatty liver disease (NAFLD). Objectives: To investigate the prevalence and incidence of MAFLD and evaluate its impacts on incident extrahepatic diseases. Methods A total of 6,873 subjects, with a 4.6-year follow-up, were included into this study. Associations of MAFLD and NAFLD with diabetes, chronic kidney disease (CKD), and cardiovascular disease (CVD) were examined using logistic regression and Cox proportional hazards models. Results The prevalence of NAFLD and MAFLD was 40.3% (95% confidence interval [CI] 39.2-41.5) and 46.7% (95% CI 45.6-47.9), respectively. Additionally, 321 (4.7%) and 156 (2.3%) subjects had MAFLD with excessive alcohol consumption and hepatitis B virus (HBV) infection. During the follow-up period, the incidence of NAFLD and MAFLD was 22.7% (95% CI 21.3-24.0) and 27.0% (95% CI 25.5-28.4). MAFLD was associated with higher risks of incident diabetes (risk ratio [RR] 2.08, 95% CI 1.72-2.52), CKD (RR 1.64, 95% CI 1.39-1.94), and CVD (hazard ratio 1.44, 95% CI 1.15-1.81). Similar associations for NAFLD were observed. Furthermore, the MAFLD subgroups with excessive alcohol consumption (RR 2.49, 95% CI 1.64-3.78) and HBV infection (RR 1.98, 95% CI 1.11-3.52) were associated with higher risks of incident diabetes. Conclusions The change from NAFLD to MAFLD did not affect the associations with diabetes, CKD, and CVD much. MAFLD further identified those patients of metabolically fatty liver combined with excessive alcohol consumption and HBV infection, who had increased risks of incident diabetes compared with those of non-fatty liver.