Diabetes has seriously affected people’s health and has brought a great economic and mental burden to the country, families and individuals. Among them, diabetic macrovascular complications (including hypertension, coronary heart disease and cerebrovascular disease) are the main cause of death in diabetes. And the occurrence of its macrovascular complications is closely related to dyslipidemia. What are blood lipids? Lipids are the general term for the lipids contained in the blood, which mainly include cholesterol and triglycerides. Both cholesterol and triglycerides are insoluble in water and must be encapsulated by water-soluble phospholipids and proteins in order to exist in the blood and be transported through the bloodstream. Cholesterol, triglycerides, phospholipids and proteins are combined to form a water-soluble complex called a lipoprotein. The type and number of proteins contained in a lipoprotein and the amount of cholesterol and triglycerides determine its weight. Lipoproteins in the blood also vary and are divided into high-density lipoproteins (which are characterized by high density and small particles) and low-density lipoproteins (which are characterized by low density and large particles). Is blood lipid a harmful substance? Blood lipids within a certain range are not harmful, but are essential substances for the human body. Lipids play an important role in maintaining the physiological activities of the body. Triglycerides are mainly involved in the body’s energy metabolism, releasing large amounts of energy for the body’s activities, and excess energy can be stored in the form of triglycerides. Cholesterol is the main component of cell membranes and plays a key role in stabilizing the normal function of cell membranes. Cholesterol is an important raw material for the synthesis of certain hormones, vitamin D and bile acids. Under normal conditions, the absorption, consumption and conversion of lipids in the body maintain a relative balance, so that the body’s blood lipid level remains basically stable. Elevated lipids may cause cardiovascular disease, and low triglycerides and cholesterol are seen in the advanced stages of some chronic wasting diseases. Sources of blood lipids: Blood lipids come from two sources, one is from the food we eat, and the other is from the synthesis in our body. Our daily intake of food, pork fat, animal fat,, roast duck, various fried foods, creamy pastries all contain a large amount of saturated fatty acids, which is one of the sources of triglycerides. The liver and small intestine are the main sites for triglyceride synthesis. The liver has the strongest synthesis capacity but does not store triglycerides, and after the liver and small intestine synthesize triglycerides from starch, they are released into the blood. Diet is an important factor that affects blood cholesterol levels. Only animal foods contain cholesterol; plant foods are cholesterol-free. For example, egg yolk, liver, kidney (loin), etc. are rich in cholesterol and it is better for hyperlipidemia patients to eat less or not. Most of the cholesterol in the body is synthesized by the body itself. The liver is the main site of cholesterol synthesis, and the raw material for cholesterol synthesis, like triglycerides, comes mainly from the breakdown of sugar, followed by the breakdown of food fat and body fat. Therefore, even if there is no cholesterol in food, the body can still synthesize it on its own without lacking cholesterol. The influence of food cannot be ignored, therefore, a low sugar and low fat diet is advocated in medicine.