Cholesterol testing and results
Cholesterol is a soft, wax-like substance found in all parts of the body. Your body needs a little bit of cholesterol to work properly. But too much cholesterol can clog your arteries and lead to heart disease.
Coronary heart disease is a narrowing of the small blood vessels that supply blood and oxygen to the heart. Coronary heart disease (CHD) is also cal...Read Article Now Book Mark Article
Cholesterol is a soft, waxy substance that is present in all parts of the body including the nervous system, skin, muscle, liver, intestines, and heart. It is made by the body and obtained from animal products in the diet. Cholesterol is manufactured in the liver and is needed for normal body functions including the production of hormones, bile acid, and Vitamin D. Excessive cholesterol in the blood contributes to atherosclerosis and subsequent heart disease. The risk of developing heart disease or atherosclerosis increases as the level of blood cholesterol increases.
Cholesterol blood tests are done to help you and your health care provider better understand your risk for heart disease, stroke, and other problems caused by narrowed or blocked arteries.
The ideal values for all cholesterol results depend on whether you have heart disease, diabetes, or other risk factors. Your provider can tell you what your goal should be.
Some cholesterol is considered good and some is considered bad. Different blood tests can be done to measure each type of cholesterol.
Your provider may order only a total cholesterol level as the first test. It measures all types of cholesterol in your blood.
You may also have a lipid (or coronary risk) profile, which includes:
- Total cholesterol
- Low density lipoprotein (LDL cholesterol)
- High density lipoprotein (HDL cholesterol)
- Triglycerides (another type of fat in your blood)
- Very low density lipoprotein (VLDL cholesterol)
Lipoproteins are made of fat and protein. They carry cholesterol, triglycerides, and other fats, called lipids, in the blood to various parts of the body.
Cholesterol and triglyceride test - Animation
Maybe you've been eating fast food more often than you should, or you're not getting your recommended two-and-a-half hours of exercise each week. Or, it could be that you smoke, or your blood pressure is too high. Well, for whatever reason, you may be concerned about your risk of getting heart disease. Well, a few tests can help you learn that risk, so you can start making healthy lifestyle changes to reduce it. A coronary risk profile is a group of blood tests that measure your cholesterol and triglyceride levels. Why is it important to know these levels? Because if you have too much of these substances in your blood from eating foods like burgers and French fries, they can clog your arteries. Eventually your arteries can become so clogged that you'll have a heart attack or stroke. Men should have their cholesterol tested by the time they're 35. Women should have it checked by age 45. If you have a condition like diabetes, heart disease, stroke, or high blood pressure, have your cholesterol checked now, no matter what your age. To measure your cholesterol, your doctor will give you a blood test. If you're also having your triglyceride level checked, you may be told not to eat or drink anything for 8 to 12 hours before the test. Depending upon your heart risk, the doctor may measure just your total cholesterol level, or your total cholesterol along with your LDL, or bad cholesterol, HDL, or good cholesterol, and triglycerides. If you're of average risk of getting heart disease, your goal is to have total cholesterol of less than 200 milligrams per deciliter, LDL cholesterol lower than 130 milligrams per deciliter, HDL cholesterol higher than 40 milligrams per deciliter if you're a man, or 50 if you're a woman -- the higher the better, and triglycerides of less than 150 also, the lower the better. Although some illnesses, like arthritis, can raise your cholesterol level, generally having high cholesterol means that you're at increased risk for heart disease and stroke. It's a sign you need to work harder to keep your heart healthy. If your cholesterol levels are normal, that's great! That means that you're eating right, you're exercising, and you're taking good care of your health. You don't need to have another cholesterol test for about five years. But if your cholesterol level is high, or you've already got heart disease, high blood pressure, or diabetes, you'll need to have your cholesterol levels checked more often. Keeping close tabs on your cholesterol and triglyceride levels is one way that you can take charge of your health, and change it for the better.
When Should You Be Tested?
Everyone should have their first screening test by age 35 for men, and age 45 for women. Some guidelines recommend starting at age 20.
You should have a cholesterol test done at an earlier age if you have:
- Heart disease
- High blood pressure
- A strong family history of heart disease
Follow-up testing should be done:
- Every 5 years if your results were normal.
- More often for people with diabetes, high blood pressure, heart disease, stroke, or blood flow problems to the legs or feet.
- Every year or so if you are taking medicines to control high cholesterol.
A total cholesterol of 180 to 200 mg/dL (10 to 11.1 mmol/l) or less is considered best.
You may not need more cholesterol tests if your cholesterol is in this normal range.
LDL (Bad) Cholesterol
LDL cholesterol is sometimes called "bad" cholesterol. LDL can clog your arteries.
You want your LDL to be low. Too much LDL is linked to heart disease and stroke.
Your LDL is most often considered to be too high if it is 190 mg/dL or higher.
Levels between 70 and 189 mg/dL (3.9 and 10.5 mmol/l) are most often considered too high if:
- You have diabetes and are between ages 40 and 75
- You have diabetes and a high risk of heart disease
- You have a medium or high risk of heart disease
- You have heart disease, history of a stroke, or poor circulation to your legs
Health care providers have traditionally set a target level for your LDL cholesterol if you are being treated with medicines to lower your cholesterol.
Treated with medicines to lower your ch...
Your body needs cholesterol to work properly. But extra cholesterol in your blood causes deposits to build up on the inside walls of your blood vess...Read Article Now Book Mark Article
- Some newer guidelines now suggest that providers no longer need to target a specific number for your LDL cholesterol. Higher strength medicines are used for the highest risk patients.
- However, some guidelines still recommend using specific targets.
HDL (Good) Cholesterol
You want your HDL cholesterol to be high. Studies of both men and women have shown that the higher your HDL, the lower your risk of coronary artery disease. This is why HDL is sometimes referred to as "good" cholesterol.
HDL cholesterol levels greater than 40 to 60 mg/dL (2.2 to 3.3 mmol/l) are desired.
VLDL (Bad) Cholesterol
VLDL contains the highest amount of triglycerides. VLDL is considered a type of bad cholesterol, because it helps cholesterol build up on the walls of arteries.
Normal VLDL levels are from 2 to 30 mg/dL (0.1 to 1.7 mmol/l).
Sometimes, your cholesterol levels may be low enough that your provider will not ask you to change your diet or take any medicines.
Understanding cholesterol results - Animation
LDL cholesterol has gotten a bad reputation, and for very good reason. Having too much of this fatty substance in your blood can clog up your arteries, preventing blood from getting to your heart and out to where it's needed in your body. Checking your LDL levels can help your doctor spot high cholesterol before it can cause a heart attack or stroke. Let's talk today about LDL tests. LDL stands for low-density lipoprotein. Lipoprotein is a type of protein that transports cholesterol, as well as fats called triglycerides and lipids, in your blood. When you eat too many fatty, cholesterol-rich foods, LDL cholesterol can start to collect in your artery walls. That's one collection you don't want, because if a chunk of that gunk breaks loose and gets lodged in a blood vessel, you could end up having a heart attack or stroke. To check your LDL cholesterol level, you'll need to have a blood test. Your doctor may tell you not to eat or drink anything for 8 to 12 hours before the test, so you can get an accurate reading. During the test, your doctor will draw blood from one of your veins. The needle might sting a little bit, but the feeling shouldn't last for any more than a few seconds. So, how do you know that you have high LDL cholesterol? Well, your LDL cholesterol level (think L for Lousy) will usually be measured along with your HDL, or good cholesterol (think H for Healthy), as well as your triglycerides and your total cholesterol level. Together, these measurements are called a lipid panel. You want your LDL level to be at least below 130 mg/dl, but ideally less than 100 milligrams per deciliter. If you're at high risk of heart disease, it should be even lower than that - less than 70 milligrams per deciliter. And for folks of average risk of getting heart disease, anything over 160 is considered a high LDL level. If you do have LDL cholesterol, you could be at risk for heart disease. Now, some folks have high cholesterol because they have an inherited condition that causes high cholesterol. If your LDL is low, it may be because you're not eating a well-balanced diet or your intestines aren't absorbing the nutrients from the foods that you eat. Ask your doctor how often you should have your LDL, and total cholesterol levels, checked. Depending upon your heart disease risks, you may need to be tested more often. If your LDL cholesterol is high, ask your doctor about cholesterol-lowering medications, diet, and other ways to bring it back down into a normal range.
Thomas S. Metkus, MD, Assistant Professor of Medicine and Surgery, Johns Hopkins University School of Medicine, Baltimore, MD. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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