A program to lower cholesterol

Part I

Understanding the Problem

The U.S. Department of Health and Human Services has developed literature to help people with unhealthy levels of blood cholesterol. It is part of the National Cholesterol Education Program, which provides guidelines for making therapeutic lifestyle changes (TLC) in diet, physical activity, and weight management to achieve healthy cholesterol levels. Even when drug treatment is needed to lower blood cholesterol, the TLC Program should still be followed.

Coming up

In the next several issues of Health monitor the TLC guidelines will be discussed. We’ll take a look at communicating with healthcare professionals, purchasing food wisely, becoming more physically active, and eating well at home and on the town.

Cholesterol—what’s healthy and what isn’t

Unhealthy high levels of cholesterol in the bloodstream pose a risk that the excess will become trapped in artery walls. Over time, it will build up in the vessel walls, making them less flexible and narrowing the passageway through which blood flows. This “hardening of arteries” is called atherosclerosis.

First, what is cholesterol? Cholesterol is a waxy, fat-like substance found in the walls of cells in all parts of the body. The body also uses it to make hormones, vitamin D, and other substances vital to the body’s functioning.

The body makes all the cholesterol it needs. Cholesterol circulates in the blood in packages called lipoproteins—fats (lipids) inside a protein wrap. (Alone, cholesterol, like other fats or oils, does not mix well with the watery blood.)

What are unhealthy levels of cholesterol?

The 2 main types of lipoproteins that carry cholesterol in the blood are:

• Low-density lipoprotein (LDL), forming what is called “bad” cholesterol—“bad” because it carries cholesterol to body tissues, including the arteries. The higher the level of LDL cholesterol in your blood, the greater your risk for heart disease.
• High-density lipoprotein (HDL), forming what is called “good” cholesterol—“good” because it carries cholesterol away from tissues and transports it to the liver, which removes it from the body. A low level of HDL cholesterol increases your risk for heart disease.

Unhealthy levels of cholesterol, then, are excessive amounts of LDL and low levels of HDL. The excess LDL cholesterol may lead to plaque buildup in the walls of blood vessels in the heart, called coronary arteries. When this happens, too little blood flows through the narrowed vessels, and not enough oxygen and nutrients reach the heart muscle. Chest pain (angina) may result.

Some cholesterol-rich plaques are unstable. They have a thin covering that can burst, releasing cholesterol and fat into the bloodstream. A blood clot may then form over the disrupted plaque, blocking blood flow through the artery—and causing a heart attack.

Know your cholesterol levels

Because high cholesterol affects the coronary arteries and is a major risk for heart disease, it is important to have your cholesterol levels checked. You could have high cholesterol and not realize it.

Most of the 65 million Americans with high cholesterol have no symptoms. So, all adults age 20 and older should have their cholesterol levels checked at least once every 5 years. If your LDL cholesterol is high, you’ll need to have it tested more often. Talk with your doctor to find out how often.

The recommended cholesterol test is called a lipoprotein profile. It measures your level of total cholesterol, which includes LDL and HDL cholesterol, and triglycerides (another type of fat found in the blood). The profile is done after you fast for from 9 to 12 hours. A small sample of blood is taken from your finger or arm.

The levels are measured as milligrams of cholesterol per deciliter of blood, or mg/dL. Table 1 gives the classifications for total, LDL, and HDL cholesterol.

What’s Your Heart Disease Risk?

Treatment for high cholesterol depends on your risk for heart disease. How many of the following risk factors for heart disease do you have?

• Cigarette smokin
• High blood pressure (140/90 mmHg or higher or being on blood pressure medication)
• Low HDL cholesterol (less than 40 mg/dL)*
• Family history of early heart disease (heart disease in father or brother before age 55; heart disease in mother or sister before age 65)
• Age (men 45 years or older; women 55 years or older).

*If your HDL cholesterol is 60 mg/dL or higher, subtract 1 from your total count.

Even though obesity and physical inactivity are not included in the bulleted list of risk factors above, they are conditions that need to be corrected. If you have 2 or more risk factors in the list above, visit www.nhlbi.nih.gov to find your risk score. Risk score refers to the chance of having a heart attack in the next 10 years, given as a percentage.

Toward a healthy goal

The main goal in treating high cholesterol is to lower your LDL level. Studies have proven that lowering LDL can prevent heart attacks and reduce deaths from heart disease in both men and women. Your efforts can slow, stop, or even reverse the buildup of plaque. They can also lower the cholesterol content in unstable plaque, making it more stable and less likely to burst and cause a heart attack.

Once you and your doctor determine your risk for heart disease, you can work toward your LDL goal. See Table 2.