On the other hand, in developed countries, anorexia nervosa was a common form of nutritional deficiency, which can cause liver damage through hunger-induced autophagy hypothesis (26), thus increasing the incidence of NAFLD in this population Together, these two factors may be responsible for the higher risk of NAFLD in people with elevated AIP (abnormal lipid metabolism) in the low BMI group. The gene discussed is AIP; the disease is nutritional deficiency disease.