Low lipoprotein can be caused by a variety of factors, including good lipid control or oral lipid-lowering medications. In elderly patients or patients with long-term chronic diseases, it is very undesirable to have a depleted lipoprotein decrease due to inadequate diet and further attention needs to be paid to nutritional intake to avoid severe malnutrition. Lipoproteins should also be categorized. HDL cholesterol is the better cholesterol, and elevated cholesterol of this lipoprotein is good for patients to prevent atherosclerosis. LDL cholesterol and lipoprotein A are the ones that promote the occurrence of atherosclerosis, and a decrease in this index means that patients have a smaller chance of developing atherosclerosis.