The causes of fatty liver generally include excessive obesity, long-term alcohol consumption, rapid weight loss, diabetes, drug factors and infectious factors. 1. Excessive obesity: the severity of fat accumulation in the liver is generally proportional to body weight, so most of the obese patients will be combined with fatty liver. 2. Long-term alcohol consumption: alcohol needs to be metabolized by the liver, and the metabolites of alcohol have a damaging effect on the liver cells, and also promote lipid deposition in the liver cells, causing alcoholic fatty liver. 3. Rapid weight loss: Losing weight too fast can easily cause fatty degeneration of fat, causing liver cell damage and fatty liver. 4. Diabetes: most diabetic patients are often combined with fatty liver, which belongs to diabetic fatty liver. 5. Drugs: drugs such as tetracycline and adrenocorticotropic hormone can cause fatty liver by inhibiting protein synthesis, resulting in fatty liver. 6. Infections: Hepatitis B virus infection may also cause fatty degeneration of liver cells, resulting in fatty liver. Fatty liver suggests that it is necessary for patients to go to regular hospitals to receive further examination and treatment according to the examination results.