Total cholesterol of 6.6mmol/L is an elevated level, not severe, and requires diet, exercise management and medication. The normal range of total cholesterol is within 5.2mmol/L, total cholesterol value 5.2-6.19mmol/L is borderline elevated, total cholesterol value >6.2mmol/L is an increased level, and severe hypercholesterolemia is defined as cholesterol concentration >7.51mmol/L or LDL cholesterol >5mmol/L. So total cholesterol 6.6mmol/L is not considered severe hypercholesterolemia. Total cholesterol 6.6mmol/L requires diet, exercise and medication, such as low-salt and low-fat diet in daily life, increasing moderate amount of physical exercise daily, and taking cholesterol-lowering medication, such as Atorvastatin Calcium Tablet, Ezetimibe and other medications for treatment. The above drugs need to be taken under the guidance of a professional doctor, do not use drugs blindly.