Starting at the age of 20, adults should get their cholesterol levels checked at least every five years. This provides a way to monitor your cholesterol levels and assess your risk for heart disease -- the leading cause of death in the United States. Because cholesterol is a fatty substance, it gets packaged into one of several types of lipoproteins, creating different types of cholesterol. Doctors can perform several types of cholesterol tests depending on the type of cholesterol they want to monitor.
Total Cholesterol
A total blood cholesterol test, also referred to as simply a cholesterol test, describes the screening test that doctors perform on adults, often performed as part of a routine physical exam. The total blood cholesterol measures all types of cholesterol, very low-density lipoprotein -- VLDL, low-density lipoprotein -- LDL, high-density lipoprotein -- HDL and triglycerides together. This test helps doctors assess your risk for heart disease. Results below 200 mg/dL indicate a low risk for heart disease, while those between 200 and 239 mg/dL call for measures to lower the levels, and results over 240 mg/dL fall into the high risk category.
HDL-C
High-density lipoprotein, HDL, carries approximately one-fourth to one-third of the cholesterol in your body. HDL picks up excess cholesterol and carries it to the liver for excretion from the body. Doctors refer to HDL as the "good" cholesterol, since it helps remove excess cholesterol. A HDL-C test provides results for the level of HDL in the blood. Doctors perform this test to determine if the HDL is high enough. Low HDL levels are associated with a higher risk for heart disease. For men, the HDL-C result should be at least 40 mg/dL and for women at least 50 mg/dL. Because the total cholesterol test and HDL-C test provide accurate results without the need for fasting, doctors can use these numbers to calculate your cholesterol ratio by dividing the total cholesterol by the HDL. The American Heart Association recommends maintaining a cholesterol ratio of 3.5 to 1 for optimal heart health.
LDL-C
Low-density lipoprotein, LDL, carries the majority of cholesterol in the body. Doctors refer to this type of cholesterol as the "bad" cholesterol because it keeps cholesterol in the blood vessels. As LDL levels increase, the cholesterol accumulates along the walls of the arteries, which increases the risk for heart disease. Although the cholesterol ratio figured using total blood cholesterol and HDL serves as a tool to assess risk, knowing the absolute LDL level is vital to diagnosing and treating high cholesterol. The LDL-C test must be performed on a fasting sample of blood to provide accurate results. The interpretation of the result varies depending on the other risk factors present. Healthy patients with no other heart disease risks may require no intervention with LDL levels as high as 160 mg/dL. Those with two or more risk factors, like high blood pressure and smoking, should keep their LDL levels less than 130 mg/dL, and those with heart disease or diabetes should strive for a LDL level under 100 mg/dL.
Lipid Profile
A lipid profile describes a group of cholesterol tests, including the total cholesterol, HDL-C and LDL-C, ordered together to provide accurate measurements of all the major types of cholesterol. A lipid profile is often performed after a total cholesterol screening returns a result considered high. In this case, to accurately assess the heart disease risk and provide a treatment plan, the doctor should know the absolute number for both HDL and LDL. A lipid profile requires a fasting blood sample to ensure the accuracy of all results. Another test often included in the lipid profile is the triglyceride test. The total cholesterol result includes the triglycerides, another type of lipid, so performing this test allows for accurate distinction and a better assessment of risk.
