Updated June 22, 2007
High cholesterol is a leading risk factor for heart disease.
Cholesterol, together with other substances, can build up inside the walls of the arteries that feed the heart and brain, forming a thick, hard deposit that can clog those arteries. When the blood flow is blocked, or partially blocked, to the heart muscle, the heart starves for oxygen, and a heart attack may result. If a clot blocks blood flow to part of the brain, a stroke may occur.
Cholesterol is produced by the liver, circulated by the bloodstream and found in all of the body's cells. It helps form cell membranes, certain hormones, Vitamin D, tissue, and helps process dietary fats.
The body manufactures all the cholesterol it needs. The rest of the cholesterol
in the bloodstream is derived from an individual's diet, with saturated
fat being the main dietary cause of high blood cholesterol. The American
Heart Association (AHA) recommends that you limit saturated fat intake
to less than seven percent of your total daily calories to maintain healthy
levels of cholesterol.
A cholesterol reading is the sum of low-density lipoprotein, or LDL (often referred to as "bad" cholesterol), high-density lipoprotein, or HDL (often referred to as "good" cholesterol), and other lipoproteins, such as trigylcerides, measured in milligrams per deciliter (mg/dL).
According to the AHA, a desirable level of total cholesterol is 200 mg/dL or less. Borderline high-risk level is between 200 and 239 mg/dL, and high risk is 240 mg/dL or greater. An even more accurate indicator than total cholesterol level is the level of LDL in the bloodstream. The lower the level of LDL cholesterol, the better.
In general, people who have a total cholesterol level greater than 240 have twice the risk of heart attack as those who have a cholesterol level of 200. This means that if your total cholesterol is less than 200 mg/dL, your heart attack risk is relatively low, unless you have other risk factors or an elevated LDL cholesterol level. No matter what your cholesterol level is, it is always better to eat foods low in saturated fat and cholesterol. Being physically active also helps reduce cholesterol levels.
How often should I have my cholesterol checked?
The CAP recommends that all people 20 years or older have their cholesterol checked at least every five years, or more frequently if recommended by their doctor. Men over the age of 45 and women older than 55 should be tested more frequently, according to their physicians' advice. This check-up should measure total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides.
- What is heart disease, and what are the risk factors?
- Management and treatment: lowering cholesterol reduces your risk of heart disease
- What happens in a cholesterol screening test? Must a doctor perform it?
- What population group is at greatest risk of high cholesterol?
The College of American Pathologists offers a free Internet-based service to remind people to schedule annual screening tests such as cholesterol tests, Pap tests, colon cancer screening tests and mammograms. Visit MyHealthTestReminder.org, select the day you would like to schedule a cholesterol test, and on that date, you will receive an e-mail reminding you to schedule an appointment. Sign up to receive a free e-mail message reminding you to have a cholesterol test at www.MyHealthTestReminder.org.
Management and treatment: lowering cholesterol reduces your risk of heart disease.
Have your blood cholesterol checked regularly. If the LDL level is high, follow your physician's recommendations to lower it.
If you are in the high-normal to borderline-high cholesterol range, diet and lifestyle changes can often improve your cholesterol levels.
- Eat foods low in saturated fat, cholesterol, and sodium
- Maintain a healthy weight and lose weight if needed. Exercise for a half-hour to an hour each day, if possible
- Don't smoke, and avoid exposure to tobacco smoke
- Reduce your alcohol consumption
- Have your blood pressure checked regularly and take steps to reduce it if it is high
If dietary changes and exercise do not produce results, your physician may prescribe a drug to lower your cholesterol.
Prescription drugs for treating high cholesterol include:
- Clofibrate (Atromid-S)
- Gemfibrozil (Lopid)
Resins, or bile acid-binding drugs:
- Cholestryamine (Questran, Prevalite, Lo-Cholest)
- Colestipol (Colestid)
- Coleseveiam (WelChol)
Statins, which disrupt the formation of cholesterol from the circulating blood:
- Atorvastatin (Lipitor)
- Fluvastatin (Lescol)
- Lovastatin (Mevacor)
- Pravastatin (Pravachol)
- Rosuvastatin Calcium (Crestor)
- Simvastatin (Zocor)
Niacin, or nicotinic acid, which affects the production of blood fats:
- Prescription niacin
- Over-the-counter niacin preparations (used under medical advisement)
- Dietary supplements (is not a substitute for prescription niacin).
In extreme cases in which there is a severe genetic cholesterol disorder, a blood-cleansing procedure called LDL apheresis may be considered. In this procedure, blood is removed from the body over a period of several hours, and is chemically cleansed of LDL cholesterol, before being returned to the body. Treatments every two to three weeks can reduce average LDL cholesterol by 50 to 80 percent, but are costly and time consuming.
What is heart disease, and what are the risk factors?
There are many forms of heart disease, including:
- Hardening of the arteries (atherosclerosis)
- Heart muscle disease (cardiomyopathy or myocarditis)
- High blood pressure, (hypertension)
- Heart defects present at birth (congenital heart disease)
- Heart attack (myocardial infarction)
- Stroke (disruption of the blood supply to the brain)
- Mini-stroke (transient ischemic attack)
- Heart failure (when the heart does not pump blood as well as it should)
Heart diseases affect more than 60 million Americans, and each year about 960,000 people die from them, according to the American Heart Association.
People who survive a heart attack have a higher chance of illness and death than the rest of the population. Both men and women have a substantial risk of another heart attack, heart failure, stroke, or sudden death.
Risk factors for heart disease:
- High blood pressure
- High LDL ("bad" cholesterol)
- Family history of early heart disease (father or brother affected before age 55; mother or sister affected before age 65)
- Physical inactivity
- Age (45 years or older for men; 55 years or older for women)
Why is LDL cholesterol considered "bad?"
LDL is thought to carry cholesterol to tissues throughout the body. An LDL level of 130 mg/dL or greater increases the risk of heart disease because at that level, LDL begins causing plaque buildup in the arteries feeding the heart and brain. Most cholesterol-lowering treatments target reduction of LDL cholesterol.
Optimal LDL: Less than 100 mg/dL
Near Optimal LDL: 100-129 mg/dL
Borderline High LDL: 130-159 mg/dL
High LDL: 160-189 mg/dL
Very High LDL: 190 mg/dL and higher
Why is HDL cholesterol considered "good?"
HDL cholesterol carries excess cholesterol to the liver for elimination from the body, and may actually protect against heart disease. An HDL level of 60mg/dL or above helps protect against heart disease, while an HDL cholesterol level of less than 40 mg/dL may result in a greater risk for heart disease.
What are triglycerides?
Triglycerides are naturally occurring compounds that are the main component of fat, both in food and in the body. Calories consumed that are not used immediately are converted into triglycerides and transported to fat cells to be stored. Hormones regulate the release of triglycerides from fat tissue so they meet the body's needs for energy between meals.
What happens in a cholesterol screening test? Must a doctor perform it?
A simple blood test can assess your cholesterol levels. You may be asked to fast, and you may be told not to take certain drugs before the test. Your health care provider will take a small blood sample. Your arm will be cleaned with antiseptic, and an elastic band briefly tightened around it to make the veins stand out. A needle will be inserted into a vein, and the blood is collected in a sterile container. The band is removed once the needle is inserted. When a small quantity of blood has been drawn, the needle is removed, and the puncture site is covered. The blood is then sent to a laboratory for analysis.
The test does not necessarily have to be performed in a doctor's office. Cholesterol testing is often offered at public and private health fairs. If you participate in one of these public screenings, make sure that a reputable company does the screening and that you share the results with your regular healthcare professional afterwards.
It is important to have a doctor interpret the results of the test. Only your doctor can correctly interpret your cholesterol numbers based on risk factors such as age, family history, smoking and high blood pressure.
Make sure the test measures LDL cholesterol and triglyceride levels in addition to total cholesterol and HDL cholesterol levels. Although knowing your total cholesterol can provide a general idea of your risk for heart disease, it is more beneficial in assessing your risk and treatment options to obtain a "lipid profile" that includes your levels of HDL cholesterol, LDL cholesterol and triglycerides, as well as your total cholesterol.
Measuring only your total cholesterol can be misleading because some people have low levels of HDL cholesterol and high levels of triglycerides, but normal or even high levels of LDL cholesterol. In these cases, a total cholesterol measurement might appear normal. Even with a "desirable" total cholesterol level, if you have high LDL or a low HDL levels, you may be at increased risk for heart disease.
What population group is at greatest risk of high cholesterol?
African-Americans have one of the highest rates of coronary artery disease in the world. Data suggests that coronary artery disease has an earlier onset and is particularly severe in this group. One other influencing factor is the decreased likelihood of early detection. Data suggests that African-Americans are less likely than Caucasians to be screened for cholesterol levels and even less likely to receive treatment.
In addition women are often at greater risk of high cholesterol. Studies done on people age 20 and older show that beginning at age 50, a greater percentage of women than men have total blood cholesterol of 200 mg/dL or higher. However, as a rule, women have higher "good" cholesterol levels than men. The female sex hormone estrogen tends to raise HDL cholesterol, which may help explain why premenopausal women are usually protected from developing heart disease. Women also tend to have higher triglyceride levels. However, as people of both sexes age, gain weight or both, their triglyceride and cholesterol levels tend to rise.
For additional information on cholesterol testing or heart disease, visit:
Sign up to receive a free e-mail message reminding you to have a cholesterol test at www.MyHealthTestReminder.org.