Fatty liver can be divided into mild, medium and severe, and it is difficult to determine it as a major or minor disease. Mild fatty liver has less impact on human body, but if it is not treated in time and develops into severe fatty liver or liver cirrhosis, it will have serious impact on human health. 1. Mild fatty liver: the reasons for the formation of fatty liver include improper diet, long-term heavy drinking, excessive obesity and so on. Fatty liver is reversible and can return to normal after reasonable treatment, so early diagnosis and treatment is very important. Prevention and treatment of fatty liver mainly rely on adjusting dietary habits and structure. 2. Severe fatty liver or cirrhosis: excessive fat can weaken the function of liver cells when they are filled with fat for a long time, which is easy to be damaged by pro-hepatic toxins and even develop into cirrhosis. Cirrhosis is irreversible and also increases the risk of liver cancer, which can have a serious impact on a person’s health. If you have risk factors for fatty liver, you should reasonably adjust your dietary habits, have regular medical checkups, and seek medical attention and standardized treatment as soon as you find out, so as not to delay your condition.