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High Cholesterol


The Manual's Editorial Staff

Last full review/revision Apr 2021| Content last modified Apr 2021
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What is cholesterol?

Cholesterol is a type of fat. Fats are also called lipids.

Your body uses cholesterol to build important parts of cells and to make certain digestive juices. Your body needs cholesterol. But having too much cholesterol in your blood (high cholesterol) for a long time can cause health problems.

  • High cholesterol over time leads to blocked arteries

  • Blocked arteries can cause heart attack, stroke, and poor circulation in your legs (peripheral arterial disease)

  • You can treat high cholesterol by exercising more, changing what you eat, and taking medicine

Where does cholesterol come from?

Cholesterol in your body comes from two places:

  • Some cholesterol comes from eating certain foods

  • Some cholesterol is made in your body from other substances

What are the different types of cholesterol?

There are several types of cholesterol. Two important types are called:

  • LDL cholesterol (bad cholesterol)

  • HDL cholesterol (good cholesterol)

Total cholesterol is the amount of all the different cholesterol types in your bloodstream.

Is high cholesterol bad?

Having a high level of LDL cholesterol for a long time causes hardening of the arteries (atherosclerosis). Your arteries clog up with a mixture of cholesterol, fats, and other substances. Your blood has trouble flowing through the clogged vessels. Sometimes blood clots form in the clogged areas and shut off blood flow completely. Shutting off blood flow to your heart causes a heart attack. Shutting off blood flow to your brain causes a stroke.

Having a high level of HDL cholesterol makes it less likely that you will get atherosclerosis. That's why HDL is called good cholesterol.

What causes high cholesterol?

Some people's body makes too much cholesterol, no matter what they eat. This kind of high cholesterol problem runs in families.

High cholesterol can also be caused by:

  • Eating a lot of foods high in fat and cholesterol

  • Having diabetes

  • Not being active

  • Drinking too much alcohol

  • Taking certain medicines

You don't have to be fat to have high cholesterol.

What are the symptoms of high cholesterol?

High cholesterol usually doesn’t cause symptoms. However, in severe cases, you might get:

  • Small yellowish bumps on your skin from excess fats (xanthomas)

How can doctors tell if I have high cholesterol?

A simple blood test can let doctors know if you have high cholesterol. Doctors recommend cholesterol testing for:

  • Children between ages 9 and 11 (earlier if they have risk factors for high cholesterol such as diabetes)

  • Adults at age 20

Adults should have a cholesterol test every 4 to 6 years.

How do doctors treat high cholesterol?

High cholesterol can be treated by:

  • Eating less fat (especially saturated fat) and cholesterol

  • Being active (for example, walking fast) at least 30 minutes per day, 5 times a week

  • Stopping smoking if you smoke

  • Taking a drug that lowers cholesterol

Foods that are low in saturated fat and cholesterol include:

  • Fruits and vegetables (whether they're fresh, frozen, canned, or dried)

  • Lean meats, like fish, skinless chicken and turkey, and lean types of beef, lamb, pork, and veal

  • Whole-grain breads and cereals, such as oatmeal, bran, rye, and multigrain

  • Low-fat dairy products, such as skim or 1% milk, nonfat or low-fat yogurt, and low-fat cheeses

  • Unsaturated vegetable oils, such as canola, olive, corn, safflower, sesame, soybean, and sunflower

Foods that are high in saturated fat and cholesterol include:

  • Butter, cream, or saturated fats and oils

  • Sausages, cold cuts, hot dogs, organ meats, spareribs, egg yolks, and fatty types of beef, lamb, and pork

  • Store-bought baked goods, such as pies, cakes, doughnuts, and high-fat cookies and crackers

  • High-fat dairy products, like whole milk, cream, half-and-half, whole-milk yogurt, most cheeses, butter, and ice cream

  • Oils that are high in saturated fat, such as coconut oil, palm oil, lard, and bacon fat

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