LDL cholesterol is the cholesterol that is often referred to as the one that tends to cause atherosclerosis, while HDL cholesterol is the one that prevents the progression of atherosclerosis and plays a role in improving the long-term prognosis. Generally speaking, it is required that LDL be lowered and HDL be appropriately raised. For people with disorders of lipid metabolism, LDL greater than 3.3 mmol/L or HDL less than 1.0 mmol/L are considered dyslipidemic. For the current guidelines, people with high risk factors for coronary heart disease, stroke and other severe atherosclerosis are required to control LDL cholesterol below 1.4mmol/L. For people with hypertension and diabetes, it should be controlled below 1.8 mmol/L as much as possible. HDL cholesterol should be kept within the normal range, not lower than 1.0mmol/L.