LDL is capable of transporting cholesterol, and when LDL levels are too high, they may accumulate in the artery walls and cause atherosclerosis, and when they are higher than the upper limit of the normal range, the body is at risk. LDL requires less than 3.12 mmol/L, but exactly how high a value is considered dangerous needs to be analyzed on a case-by-case basis. For people without underlying disease, LDL above 3.12 mmol/L is considered dangerous, when excess LDL stimulates inflammation of the blood vessel wall, resulting in vascular damage. After vascular damage, lipoproteins enter the inner wall of blood vessels and form lipids through oxidation, which can lead to blockage of blood vessels and accelerate atherosclerosis, inducing various cardiovascular diseases and possibly fatty liver. For people with cardiovascular diseases, such as coronary heart disease and cerebral infarction, LDL should not be higher than 1.28 mmol/L. For patients with diabetes and hypertension without cardiovascular diseases, LDL should not be higher than 2.6 mmol/L, otherwise it may cause life-threatening problems. High LDL values are commonly caused by eating too much fatty food or due to disease factors, such as hereditary hyperlipoproteinemia, obesity, hypothyroidism, nephrotic syndrome, and the application of androgens and glucocorticoids, which can all cause LDL to increase. When LDL is abnormal, the cause should be promptly identified and treated to keep LDL levels within a reasonable range in order to effectively achieve the goal of preventing and treating atherosclerotic cardiovascular diseases. If it is caused by diet, you should promptly adjust the diet structure, reduce the intake of fatty food, quit smoking and alcohol, and consult your doctor if you need to take medication. In case of obvious elevation, lipoproteins should be controlled in a reasonable range by appropriate means under the comprehensive judgment of doctors, and should be controlled below 3.12 mmol/L for low-risk patients, and below 2.6 mmol/L and 1.8 mmol/L for medium- and high-risk patients, respectively. Statin lipid-lowering drugs, such as atorvastatin and resulvastatin, are usually used, along with treatment of the primary disease. In daily life, attention should be paid to low-salt and low-fat diet, proper exercise to avoid obesity, and maintaining good work and rest.