Fat and fat: Fat in the human body and in pigs, cattle and sheep is mainly composed of fat. In other words, fatty meat is fat. Fat tissue consists of fat cells and triglycerides are the main component of fat cells. Simply put, fatty meat has almost the same meaning as triglycerides. Triglycerides and fatty acids: Triglycerides are an important form of energy storage for humans and are made by combining 1 glycerol with 3 fatty acids. The breakdown of triglycerides releases free fatty acids, which are used by the body to produce heat. Fatty meats and cholesterol: Fatty meats are mainly composed of triglycerides, but they also contain a higher amount of cholesterol. Triglycerides and cholesterol are both lipids and often exist together (e.g., lipoproteins contain different proportions and amounts of cholesterol and triglycerides), but their chemical structures and physiological functions are completely different. Animal oil and vegetable oil: animal oil and vegetable oil are both triglycerides, but the fatty tissues of humans, cattle and sheep mainly contain triglycerides made from glycerol and saturated fatty acids, which are solid at room temperature; while vegetable oils such as soybean oil, canola oil and peanut oil are triglycerides made from glycerol and unsaturated fatty acids, which are liquid at room temperature. It is generally believed that excessive intake of saturated fatty acids can promote the development of atherosclerotic lesions, while vegetable oils contain essential polyunsaturated fatty acids, such as docosahexaenoic acid, eicosapentaenoic acid, arachidonic acid, etc., which are beneficial to human health and may have anti-atherosclerotic effects. However, it should be noted that although vegetable oils contain polyunsaturated fatty acids and have some beneficial effects on the human body, they are also high in calories, and excessive intake can have adverse effects on the human body. Therefore, although vegetable oils are good, they should not be eaten in excess. Lipoproteins and cholesterol: Lipoproteins are composed of apolipoproteins and cholesterol (in fact, there are also triglycerides, so for the sake of simplicity, I will not mention it for the time being), and cholesterol is one of the important components of lipoproteins. Some hospital labs include total cholesterol, LDL, HDL, and very low density lipoprotein. The total cholesterol refers to the sum of cholesterol contained in all types of lipoproteins. The values of LDL, HDL and VLDL on the test are actually the values of LDL cholesterol, HDL cholesterol and VLDL cholesterol. In other words, it is the value of cholesterol contained in each of LDL, HDL or VLDL. So the way it is presented on the lab is not accurate. Why are HDL and LDL good or bad? As mentioned above, lipoproteins are made up of apolipoproteins and cholesterol. Cholesterol does not have legs of its own and does not run; its movement is controlled primarily by Apolipoproteins. High-density lipoproteins contain mainly Apo AI, which is involved in the reversal of cholesterol transport, i.e., transporting cholesterol from the arterial plaque back to the liver for processing. LDL, on the other hand, contains mainly Apo B, which carries plasma cholesterol to the vessel walls to form atheromatous plaques.