What Is HDL Cholesterol?

High-density lipoprotein (HDL) cholesterol functions to help clear fats from your bloodstream. As a result, it is known as the "good" cholesterol, in comparison to low-density lipoprotein cholesterol (LDL), which is known as the "bad" kind. Find out what these two types of cholesterol do for you, what your test results mean, and what you can do to improve your cholesterol levels.

Types and Function of Cholesterol

Cholesterol is a type of waxy fat created by your liver or introduced to your body through the foods you eat. Cholesterol is needed by your body to make new cells. Too much cholesterol, though, can be a bad thing.

Whether it's made by your liver or brought in through your diet, cholesterol circulates through your blood bound to lipoproteins. High-density lipoproteins carry more cholesterol molecules than low-density lipoproteins.

LDL cholesterol is seen as the "bad" version of this substance, because it carries cholesterol into artery walls, depositing cholesterol where it doesn't belong. This can result in plaques that cause your arteries to narrow and become more rigid—a condition called atherosclerosis.

Pieces of these plaques can fall off, or blood clots can form in your narrowed vessels. These clots may go on to cause a heart attack or stroke.

HDL cholesterol, on the other hand, is considered "good," because it helps to clear fats from the bloodstream, returning these molecules to the liver, where they are removed as waste. HDL can even help clear some of the cholesterol deposits left behind in artery walls.

Cholesterol isn't bad unless there's too much of it or you have the wrong balance of cholesterol. Cholesterols and triglycerides are the two main types of fats (lipids) in the body. Cholesterols are only found in animal products, or are produced by the liver.

In a healthy individual, the liver will make all the cholesterol you need to maintain your body's normal function. If you consume too many fats in your diet, your cholesterol could rise too much.

Triglycerides can rise if you eat too much sugar, drink too much alcohol, or consume too much fat or calories overall. They can also rise if you have uncontrolled diabetes or take certain medications. As triglycerides enter the body, cholesterol moves them through the bloodstream.

Why Is HDL Good?

HDL cholesterol is good because it helps move extra cholesterol through your body, keeping it from building up on artery walls. Ideally, you will have a balance, with lower levels of LDL cholesterol and higher levels of HDL cholesterol.

Statistics about cholesterol include:

• In the United States, cardiovascular disease is the leading cause of death in adults. High cholesterol is a primary risk factor in cardiovascular disease.
• Of adults age 20 and older, 11.8% have a total cholesterol of 240 mg/dL or more.
• The average total cholesterol level for adults over age 20 in the United States is 191 mg/dL.
• Of adults in the U.S., 18% (28.5% of men and 8.9% of women) have low HDL cholesterol levels.
• Low HDL cholesterol is more prevalent in the United States among people of Hispanic descent than those from other ethnic groups.

Risk Factors for Low HDL Cholesterol

Just as high LDL cholesterol levels can increase your risk of cardiovascular disease, so can low HDL levels. A number of factors have been associated with low HDL levels. These include:

• Genetics
• Lack of exercise or an overall sedentary lifestyle
• Unhealthy diet
• Obesity
• Uncontrolled diabetes
• Smoking
• Metabolic syndrome

Testing

The American Heart Association recommends that all adults over age 20 have their cholesterol checked every four to six months. After age 40, your healthcare provide may want to monitor your cholesterol more closely based on your individual risk.

To measure your cholesterol, your healthcare provider will order a simple blood test. While it used to be a requirement to fast for nine to 12 hours before having your blood drawn for a cholesterol test, recent national guidelines no longer call for fasting. For HDL levels, in particular, fasting has very little if any bearing on your test results.

After your blood is drawn, the sample will be analyzed in a lab, with measurements of your triglycerides and both HDL and LDL cholesterol provided to your healthcare provider. Your pracitioner will be able to make recommendations to you using these results along with your age, gender, family history, and other individual risk factors.

Want to better understand what your test results mean? Start by inputting your results into our lipid test analyzer below. It can help you see what your values may mean for your health so you can follow up appropriately with your healthcare provider.

Improving HDL Cholesterol Levels

If your cholesterol levels are out of balance, you can make lifestyle changes or take medications to help. These include:

• Avoiding trans fats
• Reducing consumption of saturated fats
• Exercising
• Quitting smoking

Medication Management

When lifestyle changes aren't enough to keep your cholesterol in check, your healthcare provider may prescribe you medications that lower your LDL cholesterol.

A number of CETP inhibitors, such as torcetrapib and dalcetrapib, initially raised hopes for their potential ability to raise HDL. However, clinical trials of these CETP inhibitors were stopped for lack of effect or adverse side effects. Research indicates that, while these medications may help increase HDL cholesterol, they are not that effective in lowering overall cardiovascular risk—and may in fact cause other problems.

Due to the failure of these and other HDL-raising medications—such as niacin or Lopid (gemfibrozil)—to show benefit over harm in recent large-scale clinical outcome trials, no medications are currently recommended for the treatment of HDL cholesterol.

As a result, medications that work to decrease LDL cholesterol levels are most often used, and may also result in increased HDL levels. These include:

• Altoprev (lovastatin)
• Caduet (amlodipine- atorvastatin)
• Colestid (colestipol)
• Crestor (rosuvastatin)
• Fibrates
• Lescol XL (fluvastatin)
• Lipitor (atorvastatin)
• Livalo (pitavastatin)
• Praluent (alirocumab)
• Pravachol (pravastatin)
• Prescription niacin
• Prescription omega-3 fatty acid supplements.
• Prevalite (cholestyramine)
• Repatha (evolocumab)
• Vytorin (ezetimibe-simvastatin)
• Welchol (colesevelam)
• Zetia (ezetimibe)
• Zocor (simvastatin)

A Word From Verywell

Cholesterol is something your body makes and needs to create cells. Too much isn't good, though, and you should have your cholesterol check at least every six years. If your cholesterol levels need work, diet and exercise are the best options, but your healthcare provider may also prescribe you medications that can help.