Combined with previously published data indicating that CSAD is reduced under western-diet stimuli [20] and CSAD gene polymorphism (rs11170445) is associated with the occurrence of type 1 diabetes through genome-wide association analysis (GWAS) [21], we believe that the downregulation of CSAD expression may be closely related to metabolism, especially for NAFLD. The gene discussed is CSAD; the disease is type 1 diabetes mellitus.