Non-alcoholic fatty liver disease

　　Non-alcoholic fatty liver disease (NAFLD) is divided into two major categories: primary and secondary. The former is related to insulin resistance and genetic susceptibility, while the latter is caused by certain special reasons. Fatty liver related to excessive nutrition and rapid weight gain or overweight, obesity, diabetes, hyperlipidemia, and other metabolic syndrome-related fatty liver, as well as cryptogenic fatty liver, all belong to the category of primary non-alcoholic fatty liver disease; while fatty liver caused by malnutrition, total parenteral nutrition, rapid weight loss after weight loss surgery, drug/environmental and industrial toxicant intoxication, and other factors belong to the category of secondary non-alcoholic fatty liver disease.

　　Non-alcoholic fatty liver disease often complicates with obesity, diabetes, hyperlipidemia, hypertension, coronary atherosclerotic heart disease (shortened as coronary heart disease), gout, cholelithiasis, and other metabolic syndrome-related symptoms. Severe fatty liver patients may have ascites and lower limb edema, and other symptoms such as spider nevus, gynecomastia, testicular atrophy, impotence in men, and amenorrhea and infertility in women.There is no direct causal relationship between non-alcoholic fatty liver disease and liver cancer. Liver cancer rarely occurs. However, if it develops into liver cirrhosis or the cause of fatty liver also plays a role in the formation of liver cancer, the incidence of liver cancer will increase..

　　Patients with non-alcoholic fatty liver disease often have no自觉 symptoms, while some patients may have non-specific symptoms and signs such as fatigue, poor digestion, hidden pain in the liver area, enlargement of the liver and spleen. Patients may have symptoms related to metabolic syndrome, such as overweight and (or) visceral obesity, increased fasting blood glucose, dyslipidemia, hypertension, etc.

　　To prevent non-alcoholic fatty liver disease, it is necessary to change bad living habits, specifically as follows.

　　1. Rational diet:The daily three meals should be reasonably balanced, with a combination of coarse and fine foods and a balanced nutrition. Sufficient protein can reduce the occurrence of fatty liver.

　　2. Appropriate exercise:Regular physical exercise should be maintained every day, and appropriate sports projects should be chosen according to one's physical condition, such as jogging, playing table tennis, badminton, and other sports. It is necessary to start with small amounts of exercise and gradually increase to an appropriate amount to enhance the consumption of internal fat.

　　3. Be cautious with medication:Any drug entering the body must pass through the liver for detoxification. Therefore, do not take medicine casually. For patients with fatty liver who have symptoms, it is especially important to be cautious and prevent the toxic and side effects of drugs, especially those that are harmful to the liver, to avoid further damaging the liver.

　　4. Keep a cheerful mood:Not to be angry or irritable, to pay attention to the combination of work and rest, etc., is also very important.

　　5. Control energy intake:Energy supply should not be too high. For patients with fatty liver who engage in light activity and have a normal weight, the daily energy supply per kilogram should be 126-147 KJ (30-35 kcal) to prevent weight gain and avoid exacerbating fat accumulation. For those who are overweight or obese, the goal is to control or reduce weight to achieve an ideal or appropriate weight.

　　Non-alcoholic fatty liver disease should undergo imaging examinations, histopathological examinations, and serological examinations, specifically as follows.

　　1. Imaging examination: Ultrasound, CT, and MRI are effective tools for diagnosing fatty liver. Among them, B-ultrasound has high sensitivity, CT has strong specificity, and MRI is valuable in distinguishing focal fatty liver and intraparenchymal focal lesions. Additionally, CT and MRI can semi-quantitatively analyze the fat content within the liver. However, the existing imaging examinations cannot reflect the presence of inflammation and fibrosis in fatty liver and cannot accurately judge the severity of liver function damage and its etiology. Therefore, imaging examinations cannot classify NAFLD into clinical and pathological types.

　　2. Histopathological examination: It can classify NAFLD into clinical and pathological types.

　　3. Serological examination.

　　In addition to general treatment, patients with non-alcoholic fatty liver disease should also pay attention to dietary health care, specifically as follows:

　　1. It is advisable to supplement more vitamins, and it is recommended to provide foods rich in various vitamins (such as B vitamins, folic acid, vitamin C, B12, A, D, E, K, etc.).

　　2. Supplement dietary fiber and minerals, avoid overly refined diets, and balance coarse and fine grains, choose more vegetables, fruits, and fungi, to ensure sufficient intake of dietary fiber.

　　3. Choose skim milk or yogurt.

　　4. Often eat low-fat soy products and wheat gluten.

　　5. Consume 500 grams of fresh green vegetables daily.

　　6. Foods like yam, sweet potato, taro, and potatoes should be alternated with staple foods like rice and flour, and the total amount should be limited.

　　7. Limit the daily salt intake to 5-6 grams.

　　8. Eat seafood such as fish and shrimp regularly.

　　9. Eat more foods that lower cholesterol, such as oatmeal, millet, and coarse grains, black sesame, black fungus, kelp, laver, and green, fresh vegetables like cauliflower.

　　10. Use 30 grams of hawthorn and 15 grams of cassia seed, add 1000 milliliters of water to make it as tea.

　　The treatment for non-alcoholic fatty liver disease includes general treatment and surgical treatment, specifically as follows.

　　1. Treat the primary disease:Prevent and treat the primary disease or related risk factors.

　　2. Basic treatment:Establish reasonable energy intake and dietary structure adjustment, moderate amount of aerobic exercise, correct bad lifestyle and behavior.

　　3. Avoid exacerbating liver damage:Prevent rapid weight loss, drug abuse, and other factors that may induce the deterioration of liver disease.

　　4. Weight loss:All NAFLD patients with overweight, visceral obesity, and rapid weight gain in the short term need to control weight and reduce waist circumference through lifestyle changes. For those with a decrease in weight of 27kg/m2 per month combined with abnormalities in two or more indicators such as blood lipids, blood glucose, and blood pressure after 6 months of basic treatment, it can be considered to add weight loss drugs such as sibutramine or orlistat, and the weight loss should not exceed 1.2Kg per week (not exceeding 0.5Kg per week for children); For those with BMI>40kg/m2 or BMI>35kg/m2 combined with sleep apnea syndrome and other obesity-related diseases, biliopancreatic diversion surgery can be considered for weight loss.

　　5. Insulin sensitizers:For patients with type 2 diabetes, impaired glucose tolerance, increased fasting blood glucose, and visceral obesity, the use of metformin and thiazolidinedione drugs can be considered to improve insulin resistance and control blood glucose.

　　6. Hypolipidemic drugs:For patients with dyslipidemia who have been treated with basic treatment and/or weight loss and hypoglycemic drugs for more than 3-6 months, and still present with mixed hyperlipidemia or hyperlipidemia combined with two or more risk factors, it is necessary to consider adding betaine, statins, or probucol and other hypolipidemic drugs.

　　7. Liver disease drugs:For patients with NAFLD accompanied by abnormal liver function, metabolic syndrome, still ineffective after 3-6 months of basic treatment, and those confirmed to have NASH and chronic progressive course by liver biopsy, adjuvant treatment for liver disease can be adopted, including antioxidant, anti-inflammatory, and antifibrotic agents. Depending on the properties of the drug and the degree of disease activity and stage, polyene phosphatidylcholine, vitamin E, silymarin, and ursodeoxycholic acid and other related drugs can be reasonably selected, but it is not advisable to use multiple drugs at the same time.

　　8. Liver Transplantation:Mainly used for the treatment of NASH-related end-stage liver disease and partial cryptogenic liver cirrhosis with decompensated liver function, metabolic screening should be performed before liver transplantation. BMI>40kg/m2 is a contraindication for liver transplantation.