Cholesterol is a substance that your liver produces naturally. It’s vital for the formation of cell membranes, vitamin D, and certain hormones.
Cholesterol is a waxy, fat-like substance. It doesn’t dissolve in water and therefore can't travel through the blood by itself. Lipoproteins are other particles formed in the liver that help transport cholesterol through the bloodstream. There are several major forms of lipoproteins that are important to your health.
Low-density lipoproteins (LDL), also known as "bad cholesterol," may build up in the arteries and lead to serious health problems like a heart attack or stroke. High-density lipoproteins (HDL), sometimes called "good cholesterol," help return the LDL cholesterol to the liver for elimination.
Your liver produces all the cholesterol that you need, but fats and cholesterol are present in many of the foods we eat nowadays. Eating too many foods that contain excessive amounts of fat increase the level of LDL cholesterol in your blood. This is called having high cholesterol. High cholesterol is also called hypercholesterolemia. High cholesterol is especially dangerous when HDL cholesterol levels are too low and LDL cholesterol levels are too high.
High cholesterol typically causes no symptoms. It’s important to eat healthy and regularly monitor your cholesterol levels. When left untreated, high cholesterol can lead many health problems including a heart attack or stroke.
High cholesterol is usually made worse by eating too many unhealthy foods that are high in cholesterol, saturated fats, and trans fats. Examples of foods that contribute to high cholesterol include:
- red meat
- liver and other organ meats
- full fat dairy products like cheese, milk, ice cream, and butter
- eggs (the yolk)
- deep fried foods, like potato chips, french fries, fried chicken, and onion rings
- peanut butter
- some baked goods, like muffins
- processed foods made with cocoa butter, palm oil, or coconut oil
High cholesterol can also be genetic in many cases. This means that it’s not simply caused by food, but by the way in which your genes instruct your body to process cholesterol and fats. Genes are passed down from parents to children.
Other conditions like diabetes and hypothyroidism may also contribute to high cholesterol. Smoking can also increase cholesterol problems..
Over one-third of American adults have raised levels of LDL or "bad" cholesterol, according to the Centers for Disease Control and Prevention (CDC). People of all ages, ethnicities, and genders can have high cholesterol.
You may be at a higher risk of high cholesterol if you:
- have a family history of high cholesterol
- eat a diet containing an excessive amount of saturated fat
- are overweight or obese
- have diabetes, kidney disease, or hypothyroidism
In most cases, high cholesterol is a silent problem that typically doesn't cause any symptoms. For most people, if they have not had regular checkups and followed their cholesterol levels, their first symptoms are events like a heart attack or a stroke. In rare cases, there are familial syndromes where the cholesterol levels are extremely high (familial hypercholesterolemia). These people have cholesterol levels of 300 milligrams per deciliter (mg/dL) or higher. Such people may show symptoms from high cholesterol that are due to deposits of cholesterol (xanthomas) over their tendons or under their eyelids (xanthalasmas). While high cholesterol affects a large portion of the United States, familial hypercholesterolemia affects only about one in 500 people.
High cholesterol is very easy to diagnose with a blood test called a lipid panel. Your doctor will take a sample of blood and send it to a laboratory for analysis. Your doctor may ask that you don’t eat or drink anything (fast) for at least 12 hours prior to the test.
A lipid panel measures your total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides. The Centers for Disease Control and Prevention (CDC) defines the following blood cholesterol levels as "desirable", or what you should aim for):
- total cholesterol: less than 200 mg/dL
- LDL cholesterol: less than 100 mg/dL
- HDL cholesterol: 40 mg/dL or higher
- triglycerides: less than 150 mg/dL
These recommendations are for the general, healthy public. Cholesterol levels may be different if you already have other conditions like diabetes. Your doctor can tell you what your healthy levels should be.
Committing to exercise and a healthy diet is usually enough to decrease cholesterol levels. Sometimes medication is needed. This is especially true if LDL cholesterol levels are very high.
The most commonly prescribed medications used to treat high cholesterol are called statins. Statins work by blocking your liver from producing more cholesterol. These drugs also indirectly decrease the blood levels of LDL cholesterol and triglycerides and some of them may also raise the level of the “good” cholesterol, HDL.
Examples of statins include:
- atorvastatin (Lipitor)
- fluvastatin (Lescol)
- rosuvastatin (Crestor)
- simvastatin (Zocor)
Other medications for high cholesterol include:
- bile acid resins or sequesterants like colesevalam (Welchol), colestipol (Colestid), or cholestyramine (Prevalite)
- cholesterol absorption inhibitors, such as ezetimibe (Zetia)
There are also combination products that decrease both the absorption of the cholesterol you eat and also reduce the production of cholesterol in your liver. One example is a combination of ezetimibe and simvastatin (Vytorin).
Since a person's lifestyle typically worsens high cholesterol, lifestyle changes are crucial in order to lower it. Take these steps to help lower your cholesterol.
- Eat a diet low in saturated and trans fats. Lean meats, such as chicken and fish that are not fried, and lots of fruits, vegetables, and whole grains are helpful. Avoid fried or fatty foods as well as too many carbohydrates and processed sugars
- Eat fish containing omega-3 fatty acids, which may help lower your LDL cholesterol. Salmon, mackerel, and herring, for example are rich in omega-3s. Walnuts, ground flaxseeds and almonds also contain omega-3s.
- Avoid excessive amounts of alcohol.
- Exercise at least 30 minutes a day, five days a week.
- Quit smoking.
Herbal and Nutritional Supplements
Some foods and supplements have been suggested to help lower your cholesterol, although none have been clearly proven to do so. These include:
- oat bran (found in oatmeal and whole oats)
- blond psyllium (found in seed husk)
- ground flaxseed
Certain herbs have also been suggested to be beneficial. The level of evidence supporting these claims varies. None have been approved by the U.S. Food and Drug Administration (FDA) for treatment of high cholesterol. Some of these include:
- olive seed extract
- green tea extract
Always talk to your doctor before taking any herbal or nutritional supplement. The herbal supplement may interact with other medications you take.
Your primary care doctor will typically be the first type of doctor to measure your cholesterol levels. A lipid panel is normally done during a routine physical exam with your primary care doctor. They may refer you to a specialist if you are at a high risk of heart disease. For example, if you are overweight or you have a hard time adhering to a diet low in saturated fat or getting regular exercise.
Specialists who treat or help manage high cholesterol include the following:
- Cardiologists are doctors who specialize in disorders of the heart. A cardiologist may be necessary if you are already experiencing more serious complications from having high cholesterol like high blood pressure or atherosclerotic heart disease.
- Nutritionists or registered dietitians are professionals who can help analyze your current diet. They can help you make a personalized cholesterol-friendly diet based on what foods you like and dislike.
- Lipidologists are doctors who specialize in the study of fats in the blood. This is an emerging branch of medicine with relatively few practitioners. Although specialized training is available in lipidology, the American Board of Medical Specialties has yet to recognize lipidology as an independent medical subspecialty. A lipidologist may be able to offer additional therapeutic options if cholesterol-lowering medications and lifestyle changes don't help.
- Exercise physiologists help people create a personalized plans to get engaged in more exercise and physical activity. They are trained to help you get the maximum heart benefits from your exercise plan.
- Endocrinologists are doctors who specialize in diagnosing diseases related to the glands. An endocrinologist can help treat people who are dealing with hormonal imbalances.
Left untreated, high cholesterol can contribute to plaque formation in your arteries and lead to atherosclerosis. Over time, deposits of cholesterol (plaque) can narrow your arteries and let less blood to pass through.
Atherosclerosis is a serious condition that can result in many life-threatening complications. These complications include:
- heart attack
- angina (chest pain)
- peripheral vascular disease
- high blood pressure
- chronic kidney disease if plaque builds up in the renal arteries, which supply blood to your kidneys
High cholesterol that’s caused by genetic factors can't be prevented. There are things you can do to help lower your cholesterol to a more desirable level or prevent it from ever becoming a serious problem:
- Exercise regularly.
- Eat a healthy diet low in animal fats.
- Eat baked, broiled, steamed, grilled and roasted foods instead of fried foods.
- Choose lean meat.
- Choose low-fat or fat-free dairy products.
- Avoid fast food and junk food.
- Eat a diet high in fiber.
- Don't smoke. Smoking injures the blood vessels and greatly increases a person's risk for heart disease and stroke.
- Avoid excessive alcohol consumption. Although, moderate alcohol consumption (no more than two drinks a day) can actually raises levels of beneficial HDL cholesterol.
- Get your cholesterol checked regularly. The American Heart Association recommends having your cholesterol levels checked every four to six years if you are a health adult over the age of 20. You may need to have your cholesterol checked more often if you are at an increased risk of high cholesterol.
- Maintain a healthy weight.
If not treated, high cholesterol can cause serious problems and even death.
Treatments for high cholesterol and heart disease have improved over the years. Medicine and education have greatly reduced the number of deaths caused by heart disease and other complications.
However, high cholesterol is still a major concern in the United States due to sedentary lifestyles and poor food choices. Making positive changes to your lifestyle, including eating a healthier diet and getting more exercise, can help you live a long and healthy life.
Written by: Jacquelyn Cafasso
Medically reviewed on Oct 27, 2014 by Kenneth R. Hirsch, MD