Absorption of food after a meal and drawing blood may affect metabolic indicators in the body. Blood draws after eating a meal may increase the values of lipids and blood sugar. Therefore, fasting is required when having blood drawn for lipids, blood glucose and liver function. Under normal circumstances, carbohydrates will be digested and absorbed by the body to be converted into glucose after eating, which will result in a certain degree of increase in blood glucose level for a short period of time after meals. In addition, when the patient eats too much food or too much high-fat food, the body fat intake may exceed the body’s metabolism, and in the short term, the fat can not be metabolized, thus raising blood lipids after meals, which may affect the relevant test results. Eating before blood tests for lipids and glucose may affect the results. It is recommended that patients ask the doctor before the blood test, and the specific situation is subject to the doctor’s advice.