What Is It?
Cholesterol is a fatty substance that occurs naturally in the body. It performs several vital functions. It is needed to make the walls surrounding the body’s cells and is the basic material that is converted to certain hormones. Your body makes all the cholesterol you need. You require only a small amount of fat in your diet to make enough cholesterol to stay healthy.
The fat and cholesterol you eat are absorbed in the intestine and transported to the liver. The liver converts fat into cholesterol, and releases cholesterol into the bloodstream as low density lipoprotein (LDL) cholesterol (the “bad” cholesterol) and high density lipoprotein (HDL) cholesterol (the “good” cholesterol).
High levels of LDL cholesterol are linked to atherosclerosis, which is the accumulation of cholesterol rich fatty deposits in arteries. This can cause arteries to narrow or become blocked, slowing or stopping the flow of blood to vital organs, especially the heart and brain. Atherosclerosis affecting the heart is called coronary artery disease, and it can cause a heart attack (myocardial infarction). When atherosclerosis blocks arteries that supply blood to the brain, it can cause a stroke (cerebral infarction).
High levels of HDL cholesterol actually protect against heart attacks and strokes by removing cholesterol from the arteries and bringing it back to the liver.
Because High cholesterol levels can cause atherosclerosis, doctors recommend that people keep their cholesterol levels within a specific range. In general, adults older than 20 should try to keep their total cholesterol level below 200 milligrams per deciliter.
For a more precise assessment of the risk of atherosclerosis, your LDL cholesterol should be checked. According to guidelines established by the National Cholesterol Education Program, the desirable level for LDL cholesterol depends on whether or not a person already has a disease caused by atherosclerosis or diabetes or other risk factors for coronary artery disease. Risk factors for coronary artery disease include:
- Being a male older than 45
- Being a female older than 55
- Being a female with premature menopause
- Having a family history of premature coronary artery disease (a father or brother younger than 55 with coronary artery disease or a mother or sister younger than 65 with coronary artery disease)
- Smoking cigarettes
- Having high blood pressure
- Not having enough good cholesterol (high density lipoprotein or HDL)
The more risk factors you have, the lower your target LDL cholesterol should be. In general, an LDL cholesterol level of less than 100 is best, but less than 130 may be acceptable.
Your level of HDL cholesterol is also very important. People with levels below 40 milligrams per deciliter are more likely to develop atherosclerosis, heart disease and stroke. Levels of HDL cholesterol above 60 milligrams per deciliter are associated with less atherosclerosis and are thought to help protect against heart disease and stroke.
Most people with High cholesterol don’t have any symptoms until cholesterol related atherosclerosis causes significant narrowing of the arteries leading totheir hearts or brains. The result can be heart related chest pain (angina) or other symptoms of coronary artery disease, as well as symptoms of decreased blood supply to the brain (transient ischemic attacks or stroke).
About one out of every 500 people has an inherited disorder called familial hypercholesterolemia, which can cause extremely High cholesterol levels (above 300 milligrams per deciliter). People with this disorder develop nodules filled with cholesterol (xanthomas) over various tendons, especially the Achilles tendons of the lower leg. Cholesterol deposits also can occur on the eyelids, where they are called xanthelasmas.
Your doctor will ask if anyone in your family had or has coronary artery disease, High cholesterol or diabetes. The doctor will ask about your diet and if you have ever smoked. He or she will check your blood pressure and look for xanthomas and xanthelasmas. Your doctor can confirm a diagnosis of High cholesterol with a simple blood test.
Battling High cholesterol is a long-term effort. You can significantly decrease your cholesterol levels within six weeks by switching to a diet that is low in saturated fats, high in fruits and vegetables, and by substituting monounsaturated fats for saturated fats. The dietary changes need to be permanent to maintain lower cholesterol levels.
You may help to prevent High cholesterol by staying on a healthy diet. This means switching from high fat foods (eggs, fatty red meats, palm or coconut oil, dairy products made with whole milk) to fresh fruits and vegetables, whole grain breads and cereals, and low fat dairy products.
You can treat High cholesterol by eating a low fat, low cholesterol diet and by taking medications to lower cholesterol. The specific treatment plan will depend on your cholesterol level (including LDL cholesterol) and on your history of coronary artery disease or risk factors for coronary artery disease.
The National Cholesterol Education Program recommends the following diet:
- Saturated fat — less than 7 percent of calories
- Monounsaturated fat — about 20 percent of calories
- Polyunsaturated fat — about 10 percent of calories
- Protein — about 15 percent of calories
- Carbohydrates — about 50 percent of calories
- Fiber — about 25 grams per day
- Cholesterol — less than 200 milligrams per day
To maintain a desirable weight, you should take in only as many calories as you burn each day. If you need to lose weight, you need to take in fewer calories than you burn.
There are five classes of cholesterol lowering medications:
- Bile acid-binding resins, including cholestyramine (Questran) and colestipol (Colestid)
- Niacin (several brand names)
- Fibrates, including gemfibrozil (Lopid), fenofibrate (Tricor) and clofibrate (Abitrate)
- Statins, also called HMG-CoA reductase inhibitors, including lovastatin (Mevacor), simvastatin (Zocor), pravastatin (Pravachol), fluvastatin (Lescol) and atorvastatin (Lipitor). Statins block an enzyme called HMG-CoA reductase, which is necessary for the production of cholesterol.
- Selective inhibitors of intestinal cholesterol absorption — There is currently only one available, ezetimibe (Zetia).
In addition to dietary changes or medication, people with High cholesterol should modify their risk factors for coronary artery disease. This means keeping blood pressure at normal levels, not smoking, controlling your blood sugar, maintaining or losing weight and following a regular exercise schedule.
When To Call A Professional
Because it is possible to have High cholesterol for many years without symptoms, it is important to have your blood cholesterol level checked periodically. Current guidelines recommend that adults older than 20 undergo a full fasting lipid profile once every five years. This test measures LDL and HDL cholesterol and triglyceride levels. If the numbers are outside the desirable range, your doctor may suggest that you change your diet and monitor your cholesterol more frequently.
The effectiveness of following a healthy diet and using using medications to lower cholesterol varies from person to person. On average, diet and exercise can lower LDL cholesterol by about 10 percent to 15 percent. Medications can lower LDL cholesterol by another 20 percent to 50 percent.
Diseases and Conditions Center
All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.