Patients who have eaten a lot of fatty foods three or four days before the test may have high LDL levels, which may affect the test results. LDL is an important screening indicator in lipid screening, which mainly helps to diagnose hypercholesterolemia and assess the risk of coronary heart disease, atherosclerosis and other diseases. High-fat foods are usually avoided three days before the test. If you eat a lot of greasy food three or four days before the test, it may affect the LDL test result. In addition, you should not drink alcohol 24 hours before the blood draw. Detailed precautions for checking LDL can be consulted with your doctor.