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:
- Low-density lipoprotein (LDL), sometimes called “bad” cholesterol
- High-density lipoprotein (HDL), sometimes called “good” cholesterol.
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.
Causes of Blood Cholesterol
An unhealthy lifestyle is the most common cause of high “bad” LDL cholesterol or low “good” HDL cholesterol. However, genesthat you inherit from your parents, other medical conditions, and some medicines may also cause unhealthy cholesterol levels.
Unhealthy lifestyle habits
Unhealthy habits such as these are a common cause of unhealthy cholesterol levels:
- Eating a lot of foods high in saturated fats or trans fats, which increase “bad” LDL cholesterol. Saturated fats are found in fatty cuts of meat and dairy products. No more than 10% of your daily calories should come from saturated fats. Trans fats are often found in packaged snacks or desserts. Read the label and eat as little food with trans fats as possible.
- Lack of physical activity, such as spending a lot of time in front of a TV or computer. These patterns are linked with lower levels of “good” HDL cholesterol.
- Smoking, which lowers HDL cholesterol, particularly in women, and raises LDL cholesterol.
- Stress, which may raise levels of certain hormones, such as corticosteroids. These can cause your body to make more cholesterol.
- Drinking too much alcohol or binge drinking, which can raise your total cholesterol level.
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.
Other medical conditions
Some medical conditions may raise LDL cholesterol levels or lower HDL cholesterol.
- Chronic kidney disease
- HIV infection
- Lupus erythematosus
- Multiple myeloma
- Overweight and obesity
- Polycystic ovary syndrome (PCOS)
- Sleep apnea
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.
- Antiretroviral medicines used to treat HIV
- Arrhythmia medicines, such as amiodarone
- Beta-blockers for relieving angina chest pain or treating high blood pressure
- Chemotherapy medicines used to treat cancer
- Diuretics such as thiazide to treat high blood pressure
- Immunosuppressive medicines, such as cyclosporine, to treat inflammatory diseases or to prevent rejection after organ transplant
- Retinoids to treat acne
- Steroids, such as prednisone, to treat inflammatory diseases including lupus, rheumatoid arthritis, and psoriasis
Screening and Prevention
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.
Lipid panel tests to screen for 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:
- Age 19 or younger. Screening begins at ages 9 to 11 and should be repeated every 5 years. Screening may be performed as early as age 2 if there is a family history of high blood cholesterol, heart attack, or stroke.
- Age 20 to 65. Younger adults should be screened every 5 years. Men ages 45 to 65 and women ages 55 to 65 should be screened every 1 to 2 years.
- Older than 65. Older adults should be screened every year.
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:
- Eating healthy
- Being physically active
- Aiming for a healthy weight
- Quitting smoking
- Managing stress
- Getting enough good quality sleep
Limiting how much alcohol you drink may also lower your risk of high blood cholesterol.
Signs, Symptoms, and Complications
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:
- Carotid artery disease
- Coronary heart disease. You may feel chest pain (called angina)
- Heart attack
- Peripheral artery disease
- Sudden cardiac arrest
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.
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.
Healthy lifestyle changes
To help you lower your LDL cholesterol level, your doctor may talk to you about adopting a healthy lifestyle.
- Heart-healthy eating. heart-healthy eating includes limiting saturated and trans fats that are found in fatty cuts of meat, dairy products, and many packaged snacks or desserts. The guidelines also recommend eating fish high in omega-3 fatty acids, nuts, and certain vegetable oils such as olive oil. The Therapeutic Lifestyle Changes and DASH eating plans can help you lower your “bad” LDL cholesterol. These plans also encourage eating whole grains, fruits, and vegetables rather than refined carbohydrates such as sugar. Talk to your doctor about other nutritional changes that you can make.
- Get regular physical activity. There are many health benefits to being physically active and getting the recommended amount of physical activity each week. Studies have shown that physical activity can lower LDL cholesterol and triglycerides and raise your “good” HDL cholesterol. Before starting any exercise program, ask your doctor what level of physical activity is right for you.
- Aim for a healthy weight. If you have high blood cholesterol and overweight or obesity, you can improve your health by aiming for a healthy weight. Research has shown that adults with overweight and obesity can lower “bad” LDL cholesterol and raise “good” HDL cholesterol by losing only 3% to 5% of their weight.
- Manage stress. Research has shown that chronic stress can sometimes increase LDL cholesterol levels and decrease HDL cholesterol levels.
- Quit smoking. For free help and support to quit smoking, you may call the National Cancer Institute’s Smoking Quitline at 1-877-44U-QUIT (1-877-448-7848).
- Get enough good quality sleep. Sleep helps heal and repair your heart and blood vessels. The recommended amount for adults is 7 to 9 hours of sleep a day.
- Limit alcohol. Visit the National Institute on Alcohol Abuse and Alcoholism for resources on support and treatment to stop drinking.
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.
- Statins are the most common medicine used to treat high blood cholesterol. Studies have shown that statins lower the risk of heart attack and stroke in people with high LDL cholesterol. Statins usually don’t cause side effects, but they may raise the risk of diabetes. However, this mainly happens in people already at high risk of diabetes, such as those who have prediabetes, overweight or obesity, or metabolic syndrome. Statins may also cause abnormal results on liver enzyme tests, but actual liver damage is extremely rare. Other rare side effects include muscle damage.
- Ezetimibe may be used if you have familial hypercholesterolemia, if statins cause side effects, or if statin treatment and lifestyle changes do not lower your “bad” LDL level enough. In rare cases, ezetimibe can cause liver injury.
- Bile acid sequestrants may be prescribed if you cannot take statins or if you need to lower your cholesterol even more than a statin taken alone. This medicine may cause diarrhea, make some other medicines less effective, or raise your blood triglyceride level.
- PCSK9 inhibitors are a type of medicine that you inject under your skin every 2 or 4 weeks. Your doctor may prescribe a PCSK9 inhibitor and a statin if you are at high risk of complications like heart attack or stroke, or if you have familial hypercholesterolemia. The most common side effects are itching, pain, or swelling at the place where you injected it.
- Lomitapide may be prescribed if you have familial hypercholesterolemia. If you take lomitapide, your doctor will check your liver enzymes regularly, because this medicine can cause liver injury. Your doctor will also recommend that you take vitamin E and other supplements.
- Mipomersen may also be used to treat familial hypercholesterolemia. If you take this medicine, your doctor will regularly check your liver because of the risk of liver injury.
Living With Blood Cholesterol
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.
Monitor your condition
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.
- Take all medicines regularly, as prescribed. Do not change the amount of your medicine or skip a dose unless your doctor tells you to.
- Talk with your doctor about how often you should schedule office visits and blood tests.
- Call your doctor if you have any symptoms of complications or if you have problems with your blood pressure or blood sugar.
- Adopt a heart-healthy lifestyle. Your doctor will recommend that you make lifelong lifestyle changes, including heart-healthy eating, being physically active, quitting smoking, managing stress, and managing your weight. Your doctor may refer you to a dietitian to help you plan healthy meals and an exercise professional who can help you increase activity and improve your fitness level.
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.
Learn the warning signs of serious complications and have a plan
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 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.
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.
Learn about other precautions to help you stay safe while taking statins
Statins are the most common medicine used to treat high blood cholesterol. Learn some tips to stay safe if your doctor gives you statins.
- Keep taking your statin medicine as prescribed. If you started taking a statin after you recently had a heart attack, a stroke, or another complication, you should not stop taking this medicine on your own, because that can increase your risk for a repeat event or even death. Ask your doctor if you have any concerns about your medication or if you would like to stop or change to a different treatment.
- Ask your doctor what medicines, nutritional supplements, or foods you should avoid. Some of these can interact with statins to cause serious side effects or make them less effective. For example, grapefruit (fresh or as juice) affects how your liver breaks down some statins.
- Tell your doctor about any symptoms or side effects. Sometimes, people report muscle problems while taking statins. If you start having muscle pain, your doctor may order a blood test to look for muscle damage. The pain may go away if you switch to a different statin. Muscle damage with statins is rare, and your muscles may heal when you switch to a different medicine.
- If you are a woman who is planning to become pregnant, talk to your doctor about your options. You should stop taking statins about three months before getting pregnant. Also, you should not take statins if you are breastfeeding.