Cholesterol is the fatty substance called a lipid that is made by the liver and found in all body cells. You may have extra cholesterol when you eat food rich in saturated fat. A desirable cholesterol level is less than 200 milligrams per deciliter, or mg/dL, of blood. When you have a cholesterol test, a measure of the total cholesterol in the blood is found by adding together high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and very low-density lipoprotein cholesterol, which is 20 percent of your triglycerides. In order to get your cholesterol numbers to equal your total cholesterol, it is necessary to use the correct equation.
HDL Cholesterol -- High-Density Lipoprotein
HDL is a number factored into your total cholesterol and is known as the good cholesterol because high levels are connected with a lower heart disease risk. HDL particles carry cholesterol from your cells back to the liver for disposal. HDL particles contain less fat and more dense protein than LDL particles. A low HDL level might be related to physical inactivity, obesity or smoking. Men also tend to have lower HDL levels than premenopausal women because estrogen raises HDL. According to the American Heart Association, the desirable HDL cholesterol level for men is above 40 and for women above 50.
LDL Cholesterol -- Low-Density Lipoprotein
LDL is another number factored into your total cholesterol and is known as the bad cholesterol because high levels are associated with an increased risk for heart disease. Too much LDL in the blood causes a fatty accumulation in the arteries known as atherosclerosis. Your LDL levels may be high if you eat a diet rich in saturated fats and cholesterol. The American Heart Association indicates that an optimal LDL level is less than 100 mg/dL.
Triglycerides
Triglycerides are fats in your body that provide energy to your muscles, though a triglyceride level that is too high may lead to an increased risk of heart disease. A high triglyceride level combined with a low HDL may be the result of inactivity or an unhealthy diet. Triglycerides are the most important lipid component of VLDL, particles and 20 percent of triglycerides are considered in the total cholesterol equation. The American Heart Association states that a normal triglyceride level is 150 mg/dL.
Putting It Together
When you have a cholesterol test, your total cholesterol is determined by the following equation: Total cholesterol = HDL cholesterol + LDL cholesterol + triglycerides x 0.20. Triglycerides .20 is the same as dividing your triglycerides by 5. For example, if your HDL is 60, your LDL is 75 and your triglycerides are 100, the equation is: 60 + 75 + 100/5 = 155. Therefore, your total cholesterol is 155.
