What Is LDL Cholesterol?

Often labeled as ‘bad’ cholesterol, LDL is a type of lipoprotein particle found in your blood. At higher levels, it can contribute to heart disease.

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If left untreated, high cholesterol can lead to high blood pressure and other heart problems.Getty Images; Everyday Health

Low-density lipoprotein (LDL) cholesterol is the most common type of cholesterol found in your blood. Each LDL particle is made up of a lipoprotein coat and a cholesterol center.

Although it’s often known as the “bad” cholesterol, LDL cholesterol isn’t inherently unhealthy. Your body needs LDL cholesterol to protect nerves and produce cells and hormones.

High-density lipoprotein (HDL) cholesterol is the other type of cholesterol, and is often called “good” cholesterol. Both LDL and HDL cholesterol are produced in the liver.

At higher levels, LDL cholesterol builds up as plaque in the walls of blood vessels. Over time, this buildup can result in atherosclerosis, or hardening of the arteries.

Atherosclerosis can raise your risk of heart attack, stroke, and death. When plaques form on the arteries supplying blood to your brain, abdomen, arms, and legs, they can lead to intestinal damage and peripheral arterial disease.

High cholesterol is influenced by both genetic and lifestyle factors. Approximately 20 percent of the world’s population is thought to have elevated levels of Lp(a), or lipoprotein(a), a type of LDL cholesterol. Lp(a) is a risk factor for developing arterial plaques well before the typical age of onset for heart disease.

In a 2020 observational study of more than 283,000 adults in the United Kingdom, researchers found measured Lp(a) was associated with atherosclerotic cardiovascular disease, strengthening evidence for the cholesterol variant’s clinical significance.

Since there is no specific treatment for Lp(a), it’s important for people who are carriers to keep their LDL cholesterol levels low. Unlike overall high LDL cholesterol, which generally can be managed through lifestyle changes and medication, elevated levels of Lp(a) are largely genetically determined.

The American Heart Association (AHA) does not currently recommend universal screening for Lp(a), but some physicians, like George Thanassoulis, MD, of McGill University in Montreal, now recommend getting tested since more targeted therapy for high Lp(a) is likely to come in the near future.

Although more uncommon, there is another genetic condition that causes abnormally high cholesterol: familial hypercholesterolemia, or FH. This condition, which affects about 1 million Americans, can cause elevated LDL levels early in life, which could lead to premature heart attacks if left untreated. A blood test can confirm the diagnosis, but again, the condition is relatively rare.

Testing for high cholesterol overall, however, is recommended by the AHA. Since cholesterol isn’t something that causes symptoms until a person develops heart disease or other complications, it’s important to get tested regularly via a blood test (also known as a lipid panel). Ask your physician or primary care provider on your next visit.

LDL Cholesterol Facts

Nearly 94 million adults in the United States — almost 40 percent of the population — have total cholesterol levels higher than the normal range. Slightly more than half of adults with high cholesterol are getting treatment to lower it.

A desirable LDL level is less than 100 mg/dL. A range of 100 to 159 mg/dL is considered at-risk, and 160 mg/dL or higher is considered dangerous.

How to Lower LDL Cholesterol

Adopting healthy lifestyle habits is the first protection against high LDL cholesterol. If changing lifestyle habits alone isn’t enough, your doctor may also prescribe cholesterol-lowering medication.

Learn More About Treatment of High Cholesterol

Here are some of the AHA’s recommendations for treating and preventing high cholesterol:

Avoid a diet high in saturated and trans fats. A diet high in saturated fats — found in animal products, including full-fat dairy, as well as many processed foods — can raise your LDL and total cholesterol.

Trans fats — sometimes found in fast food and many commercially baked breads, cookies, cakes, chips, crackers, and snack foods — can also raise your LDL cholesterol and lower your HDL cholesterol.

Instead, the AHA recommends a diet rich in fruits, vegetables, poultry, fish, nuts, and nontropical vegetable oils.

Get regular exercise. The AHA recommends getting at least 150 minutes of moderate-intensity aerobic exercise each week, preferably split up over several days. If you’re new to a regular exercise routine, low-impact aerobic exercises are a good way to get started.

Exercise has two effects on cholesterol: It raises levels of your body’s HDL cholesterol, and it also increases the size of LDL particles, which makes them less likely to form plaque on coronary artery walls.

Keep blood sugar levels in check. For people with diabetes or prediabetes, it’s important to monitor your blood sugar as well. High blood sugar levels can raise LDL cholesterol, as well as lower HDL cholesterol and weaken the lining of arteries.

Keep your weight in a healthy range. Having a BMI of 30 or greater typically correlates with a higher risk of abnormal LDL and total cholesterol levels.

Watch your waistline. Beyond weight, abdominal fat and waist circumference can increase your risk of high cholesterol.

For men, a waist measurement of 40 inches (102 centimeters [cm]) or more puts you at risk. For women, it’s a waist measurement of 35 inches (89 cm) or more.

Quit tobacco. Although the habit can be hard to kick, quitting tobacco use can help prevent high cholesterol. If you don’t smoke, don’t start.

Tobacco smoke causes damage to the walls of your blood vessels, making it easier for plaque to build up in them. Smoking also lowers HDL cholesterol levels.

Cholesterol-lowering drugs. Depending on your family history, genetic risk factors, or lifestyle, sometimes healthy habits alone aren’t enough to lower LDL cholesterol.

If you and your doctor find that your numbers aren’t budging, medication may help manage your high cholesterol.

Learn More About High Cholesterol Lowering Medications

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