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Watch this video to see how cholesterol flowing through your bloodstream can build up on the wall of the blood vessel over time. This forms plaque that can partially block blood flow through the blood vessel. Medical Animation Copyright © 2020 Nucleus Medical Media, All rights reserved. Click here to view this video with an audio description.
Cholesterol is a waxy, fat-like substance that your body needs for good health, but in the right amounts. Unhealthy levels of cholesterol can lead to a condition called high blood cholesterol.
Cholesterol in your blood is carried on lipoproteins:
High levels of “bad” LDL cholesterol cause plaque (fatty deposits) to build up in your blood vessels. This may lead to heart attack, stroke, or other health problems.
“Good” HDL cholesterol returns cholesterol to your liver so it can be removed from the body. In healthy people high levels of HDL cholesterol may lower your risk of heart attack, stroke, and other health problems.
Unhealthy cholesterol levels are often caused by lifestyle habits, such as unhealthy eating patterns, in combination with the genes that you inherit from your parents.
Routine blood tests can show whether your cholesterol levels are healthy. To help get your cholesterol levels into the healthy range, you may need heart-healthy lifestyle changes or medicines.
Explore this Health Topic to learn more about high blood cholesterol, our role in research and clinical trials to improve health, and where to find more information.
An unhealthy lifestyle is the most common cause of high “bad” LDL cholesterol or low “good” HDL cholesterol. However, genes that you inherit from your parents, other medical conditions, and some medicines may also cause unhealthy cholesterol levels.
Unhealthy habits such as these are a common cause of unhealthy cholesterol levels:
Learn about heart-healthy lifestyle changes you can make to lower your risk for high blood cholesterol.
Some people may develop high “bad” LDL cholesterol because of mutations, or changes, in their genes. These may be passed from parent to child, which can cause familial hypercholesterolemia. If you have a family history of high blood cholesterol, it may be more difficult for your body to remove LDL cholesterol from your blood or break it down in the liver.
Some medical conditions may raise LDL cholesterol levels or lower HDL cholesterol.
Some medicines that you take for other health problems can raise your level of “bad” LDL cholesterol or lower your level of “good” HDL cholesterol.
Your risk for high blood cholesterol may be higher because of your age, family history and genetics, race or ethnicity, or sex.
Unhealthy levels of cholesterol can affect people of all ages, even young children. However, high cholesterol is most commonly diagnosed in people between the ages of 40 and 59. As you age, your body’s metabolism changes. Your liver does not remove “bad” LDL cholesterol as well as it did when you were young. These normal changes may increase your risk for developing high blood cholesterol as you get older.
Family members usually have similar cholesterol levels. This suggests that your genes can raise your risk of having unhealthy cholesterol levels.
In addition, your genes may raise your risk for another type of “bad” cholesterol. High levels of lipoprotein-a, also called Lp(a), may mean you are at high risk of heart or blood vessel diseases, even if your other cholesterol levels are healthy. Genes determine how much Lp(a) you have. Your Lp(a) level is unlikely to change much from childhood to old age.
Lp(a) is not usually part of a routine lipid panel. Your doctor may order an Lp(a) test if you have a family history of early heart or blood vessel disease, such as heart attack, or do not know your family medical history. If you have a high Lp(a) level, your doctor may prescribe a statin to prevent heart and blood vessel disease, even if your other cholesterol levels are in the healthy range.
Your race or ethnicity may affect your risk of high blood cholesterol.
Between the ages of 20 and 39, men have a greater risk for high total cholesterol than women. Women are more likely to have high blood cholesterol than men at other ages. Women usually have higher levels of “good” HDL cholesterol.
Conditions and medicines that may raise a woman’s risk for high blood cholesterol include:
Your doctor may order a blood test called a lipid panel to screen for unhealthy cholesterol levels. Adopting a heart-healthy lifestyle starting in childhood and continuing throughout your life can help prevent high blood cholesterol.
A lipid panel usually measures total cholesterol, LDL cholesterol, and HDL cholesterol. Your test results may also show the level of non-HDL cholesterol, which includes all fats (including "bad" LDL cholesterol) that raise your risk of heart and blood vessels diseases. It may also include a test for triglycerides.
Ask your doctor if you need to fast before a lipid panel. This means you do not eat or drink anything except water for 9 to 12 hours before your visit. Ask your doctor about taking your medicines before the test.
How often you get a lipid panel done depends on your age, risk factors, and family history of high blood cholesterol or cardiovascular diseases, such as atherosclerosis, heart attack or stroke. Here is a general guide:
If your blood cholesterol levels are not within the healthy range for your age and sex, your doctor may order a repeat lipid profile test, especially if you were not fasting before your first lipid panel. Also, it is important to know that your risk of coronary heart disease and stroke is based on several other factors, not just your cholesterol levels. These factors include things like your age, race, and lifestyle habits.
Living a heart-healthy lifestyle may help prevent unhealthy levels of blood cholesterol. This includes:
Limiting how much alcohol you drink may also lower your risk of high blood cholesterol.
High “bad” LDL cholesterol usually does not cause symptoms, so most people do not know they have it until they are tested during a routine doctor’s visit. Very high levels may cause symptoms such as fatty bumps on your skin, called xanthomas, or grayish-white rings around the corneas in your eye, called corneal arcus. These mostly develop in people who have familial hypercholesterolemia.
Undiagnosed or untreated high blood cholesterol can lead to serious problems, such as heart attack and stroke.
High blood cholesterol can lead to a condition called atherosclerosis, in which plaque builds up in the blood vessels throughout your body. Over time, uncontrolled high blood cholesterol can cause the following heart or blood vessel diseases:
Your doctor may use a risk calculator to estimate the chances of having one of these complications in the next 10 years or over your lifetime. For example, the Atherosclerotic Cardiovascular Disease (ASCVD) Estimator considers your cholesterol levels, age, sex, race, and blood pressure. It also factors in whether you smoke or take medicines to manage your high blood pressure or cholesterol.
Talk with your doctor about your cholesterol levels and your risk of developing heart and blood vessel disease. Knowing your level of risk helps your doctor decide whether you need medicine to treat high cholesterol and what healthy lifestyle changes you may need to make to lower your risk.
To treat complications, you may need heart-healthy lifestyle changes, medicines, surgery, or other procedures. Certain medical devices, such as a stent to hold open a narrowed artery or a pacemaker to correct a rhythm disorder, can help keep your heart healthy. Learn more about steps you can take to prevent complications from high blood cholesterol.
Do you know how high blood cholesterol can cause complications?
Your cells need some cholesterol but too much can cause problems. Cholesterol in your blood is carried on lipoproteins such as HDL and LDL. HDL carries cholesterol to your liver, where it can be removed from the body. In this way, HDL cholesterol helps protect your heart from atherosclerosis. That’s why HDL cholesterol is sometimes called “good” cholesterol.
LDL carries most of the cholesterol in your blood to tissues throughout the body. LDL cholesterol is removed from the blood by the liver to be reused or removed from the body. When LDL cholesterol in the blood is too high, the liver cannot remove all of it. Instead, the LDL cholesterol builds up in the blood vessels, leading to atherosclerosis. That’s why LDL cholesterol is sometimes called “bad” cholesterol.
Your doctor will diagnose you with high blood cholesterol based on blood tests of your cholesterol levels, your medical and family history, and a physical exam. Your doctor may do other tests to assess your risk of complications from high blood cholesterol.
A lipid panel usually measures total cholesterol, LDL cholesterol, and HDL cholesterol. Your test may also show the level of non-HDL cholesterol, which includes LDL and all other types of “bad” cholesterol that raise your risk of atherosclerosis and complications.
Your doctor may diagnose you with high blood cholesterol if your total or non-HDL cholesterol level is higher than what is healthy for you. Your doctor might also find that your level of “good” HDL cholesterol is too low.
Your doctor may ask that you fast before a lipid panel. This means you do not eat or drink anything except water for 9 to 12 hours before your blood is drawn. Ask you whether you should take your usual medicines before the test and if there are any other special instructions.
Your doctor may order other tests to help decide whether medicines are needed to lower your risk of heart and blood vessel diseases. These may include a coronary calcium scan, and blood tests for levels of C-reactive protein (CRP) and lipoprotein-a.
Your doctor will ask about your eating habits, physical activity, family history, medicines you are taking, and risk factors for heart or blood vessel diseases.
During your physical exam, your doctor will check for signs of very high blood cholesterol, such as xanthomas, or signs of other health conditions that can cause high blood cholesterol.
Unhealthy blood cholesterol levels are treated with heart-healthy lifestyle changes and medicines. People who have familial hypercholesterolemia may need special procedures.
If a medical condition or medicine is causing your blood cholesterol problem, your doctor may treat the condition or change your medicine or its dose.
Talk with your doctor about your cholesterol levels, your risk of developing heart or blood vessel disease, other medical conditions you have, and your lifestyle. Your doctor can tell you about the benefits and side effects of medicines for lowering your blood cholesterol. Together, you can set up a treatment plan that will work for you.
To help you lower your LDL cholesterol level, your doctor may talk to you about adopting a healthy lifestyle.
Depending on your risk for complications such as heart attack and stroke and whether you are able to lower your high blood cholesterol levels with lifestyle changes alone, your doctor may prescribe a medicine.
If your doctor prescribes medicines as part of your treatment plan, be sure to continue your healthy lifestyle changes. The combination of the medicines and heart-healthy lifestyle changes can help lower and control your blood cholesterol levels.
Doctors now have a range of medicines they can prescribe to treat high blood cholesterol.
Want to know how these medicines work to manage cholesterol?
Some people with familial hypercholesterolemia may benefit from lipoprotein apheresis to lower their blood cholesterol levels. Lipoprotein apheresis is similar to dialysis, in that it uses a filtering machine to remove unwanted substances from the body. In lipoprotein apheresis, the machine removes “bad” LDL cholesterol from the blood, then returns the remainder of the blood to your body.
If you have been diagnosed with unhealthy levels of blood cholesterol, it is important that you continue your treatment. Follow-up care depends on your cholesterol levels, your risk of complications such as a heart attack or a stroke, and your response to treatment.
Follow up with your doctor regularly to see how well your treatment is working, whether you need to add or change medicines, and whether your health condition has changed.
If heart-healthy lifestyle changes alone are not enough, your doctor may prescribe a statin or another medicine to help lower and control your high blood cholesterol levels.
If you start taking a statin or another cholesterol medicine, your doctor may order a lipid panel one to three months later to see whether the drug is working. Repeat tests may be done every three to 12 months after that to make sure your cholesterol levels remain healthy.
High blood cholesterol can lead to serious cardiovascular complications, such as heart attack or stroke. If you think that you are or someone else is having the following symptoms, call 9-1-1 immediately. Every minute matters.
Heart attack
Heart attack symptoms include mild or severe chest pain or discomfort in the center of the chest or upper abdomen that lasts for more than a few minutes or goes away and comes back. This discomfort can feel like pressure, squeezing, fullness, heartburn, or indigestion. There also may be pain down the left arm or in the neck. Although both men and women can experience these symptoms, women are more likely to have other, less typical symptoms, such as shortness of breath, nausea, vomiting, unusual tiredness, and pain in the back, shoulders, or jaw. Read more about the signs and symptoms of a heart attack.
Stroke
If you think someone may be having a stroke, act F.A.S.T. and perform the following simple test.
F—Face: Ask the person to smile. Does one side of the face droop?
A—Arms: Ask the person to raise both arms. Does one arm drift downward?
S—Speech: Ask the person to repeat a simple phrase. Is their speech slurred or strange?
T—Time: If you observe any of these signs, call 9-1-1 immediately. Early treatment is essential.
Read more about the signs and symptoms of a stroke.
Statins are the most common medicine used to treat high blood cholesterol. Learn some tips to stay safe if your doctor gives you statins.
The NHLBI is part of the U.S. Department of Health and Human Services’ National Institutes of Health (NIH)—the Nation’s biomedical research agency that makes important scientific discoveries to improve health and save lives. We are committed to advancing science and translating discoveries into clinical practice to promote the prevention and treatment of heart, lung, blood, and sleep disorders, including high blood cholesterol. Learn about current and future NHLBI efforts to improve health through research and scientific discovery.
Learn about the following ways the NHLBI continues to translate current research into improved health for people who have high blood cholesterol. Research on this topic is part of the NHLBI’s broader commitment to advancing heart and vascular disease scientific discovery.
Learn about some of the pioneering research contributions we have made over the years that have improved clinical care.
In support of our mission, we are committed to advancing high blood cholesterol research in part through the following ways.
Learn about exciting research the NHLBI is exploring in the area of high blood cholesterol.
We lead or sponsor many studies on high blood cholesterol. See if you or someone you know is eligible to participate in our clinical trials and observational studies.
To learn more about clinical trials at the NIH Clinical Center or to talk to someone about a study that might fit your needs, call the Office of Patient Recruitment 800-411-1222.
Learn more about participating in a clinical trial.
View all trials from ClinicalTrials.gov.
After reading our High Blood Cholesterol Health Topic, you may be interested in additional information found in the following resources.
The Center for Translation Research and Implementation Science (CTRIS) and the Division of Cardiovascular Sciences ...