High Cholesterol
content provided by Healthwise
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Overview What is high cholesterol? Cholesterol is a type of fat called a lipid. The body uses it for many things, such as making new cells. Your liver makes the cholesterol that your body needs. You also get cholesterol from the foods you eat. |
Your body needs some cholesterol. But if you have too much, it starts to build up in your arteries. (Arteries are the blood vessels that carry blood away from the heart.) This is called hardening of the arteries, or atherosclerosis. It is usually a slow process that gets worse as you get older.
To understand what happens, think about how a clog forms in the pipe under a kitchen sink. Like the buildup of grease in the pipe, the buildup of cholesterol narrows your arteries and makes it harder for blood to flow through them. It reduces the amount of blood that gets to your body tissues, including your heart. This can lead to serious problems, including heart attack and stroke.
A simple blood test tells you how much cholesterol you have. The test results are given in mg/dL of cholesterol but most people just say the numbers. Your cholesterol numbers help your doctor know your risk of heart attack. To know this risk, your doctor will also take into account other factors like your age, blood pressure, family history, and if you smoke.
For a general idea about your total cholesterol number, compare your number to the following:
Best is less than 200.
Borderline-high is 200 to 239.
High is 240 or above.
What are the symptoms?
High cholesterol doesn't make you feel sick. But if cholesterol builds up in your arteries, it can block blood flow to your heart or brain and cause a heart attack or stroke.
By the time you find out you have it, it may already be clogging your arteries. So it is very important to start treatment even though you may feel fine.
What are the different kinds of cholesterol?
Cholesterol travels through the blood attached to a protein. This package of cholesterol (a lipid) and protein is called a lipoprotein. Lipoproteins are either high-density or low-density, based on how much protein and fat they have.
- Low-density lipoproteins (LDL) are the “bad” cholesterol. LDL is mostly fat with only a small amount of protein. It can clog your arteries. If you have high cholesterol, your doctor will want you to lower your LDL.
- High-density lipoproteins (HDL) are the “good” cholesterol. HDL is more protein than fat. It helps clear the bad cholesterol from your blood so it does not clog your arteries. A high level of HDL can protect you from a heart attack.
- Triglycerides are another type of fat in the blood that can affect your health. If you have high triglycerides and high LDL, your chances of having a heart attack are higher.
It may help to think of HDL as the “Healthy” cholesterol and LDL as the “Lousy” cholesterol. Or you could remember that HDL should be High and LDL should be Low.
Experts have come up with goals for each type of cholesterol. Your doctor will help you decide on cholesterol goals based on your risk of heart attack and stroke. Your doctor will help you know this risk. To find out your risk of a heart attack, you can use the Interactive Tool: Are You at Risk for a Heart Attack?
- LDL should be low. Your LDL goal depends on your risk of heart attack and stroke. If you are at very high risk, your goal may be less than 70. If you are at high risk, your goal is less than 100. If you are at moderate risk, your goal is less than 130. If you are at low risk, your goal is less than 160.
- HDL should be high. A good HDL goal is 40 or higher. HDL over 60 helps protect against a heart attack. HDL below 40 increases your risk of heart problems. A high HDL number can help offset a high LDL number.
- Triglycerides should be less than 150. A level above 150 may increase your risk for heart problems.
What causes high cholesterol?
Many things can cause high cholesterol, including:
- Diet. Eating too much saturated fat, trans fat, and cholesterol can raise your cholesterol. Saturated fat, trans fat, and cholesterol are in foods that come from animals (such as meats, whole milk, egg yolks, butter, and cheese), many packaged foods, and snack foods like cookies, crackers, and chips.
- Weight. Being overweight may raise triglycerides and lower “good” HDL.
- Activity level. Not exercising may raise “bad” LDL and lower HDL.
- Overall health. Diseases such as hypothyroidism can raise cholesterol. Smoking may lower HDL.
- Age. Cholesterol starts to rise after age 20. In men, it usually levels off after age 50. In women, it stays fairly low until menopause. After that, cholesterol levels rise to about the same levels as in men.
- Family. Some people inherit a rare disease called a lipid disorder. It can cause very high total cholesterol, very low HDL, and high triglycerides. If you have this problem, you will need to start treatment at a young age.
How is high cholesterol diagnosed?
Doctors use a blood test to check cholesterol.
- A fasting cholesterol test (also called a lipoprotein analysis) is the most complete test. It measures total cholesterol, HDL, LDL, and triglycerides. You cannot have food for 9 to 12 hours before this test.
- A direct LDL test measures your LDL level only. You can have this test done at any time, even if you recently had a meal or snack.
- A simple cholesterol test can measure total cholesterol and HDL. You can eat before this test. Sometimes doctors do this test first. If it shows you have high cholesterol or low HDL, then you will get a fasting cholesterol test.
How is it treated?
The two main treatments are lifestyle changes and medicines. The goal of treatment is to lower your "bad" LDL cholesterol and reduce your risk of a heart attack. You may also need to raise your "good" HDL cholesterol. A high level of HDL helps reduce your risk of heart problems.
Some lifestyle changes are important for everyone with high cholesterol. Your doctor will probably want you to:
- Follow the Therapeutic Lifestyle Changes (TLC) diet. The goal is to reduce the amount of saturated fat you eat. Eating saturated fat raises your cholesterol. The TLC diet helps you learn to make better food choices by picking lean meats, low-fat or nonfat products, and good fats like olive and canola oils.
- Lose weight, if you need to. Losing just 5 lb to 10 lb (2.3 kg to 4.5 kg) can lower your cholesterol and triglycerides. Losing weight can also help lower your blood pressure.
- Be more active. Exercise can raise your “good” HDL and may help you control your weight.
- Quit smoking, if you smoke. Quitting can help raise your HDL and improve your heart health.
Sometimes lifestyle changes are enough on their own. But if you try them for a few months and they don't lower your cholesterol enough, your doctor may prescribe a cholesterol-lowering medicine called a statin. You also may need medicines to lower triglycerides or raise HDL.
You may need to start taking medicine right away if your cholesterol is very high or if you have another problem that increases your chance of having a heart attack. People who have a high risk for heart attack benefit from taking higher doses of statins to lower their LDL cholesterol as much as possible. The more these people can lower their LDL, the less likely they are to have a heart attack.1 To find out your risk, use the Interactive Tool: Are You at Risk for a Heart Attack?
It is important to take your medicine just the way your doctor tells you to. If you stop taking your medicine, your cholesterol will go back up.
You will need to have your cholesterol checked regularly. Your results can help your doctor know if lifestyle changes have helped or if you need more or different medicines.
More information
Last Updated: July 11, 2008
Author: Robin Parks, MS
Medical Review: E. Gregory Thompson, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
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This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.
Lipids,
such as cholesterol, triglycerides, and fatty acids, are fat and substances like fat used as a source of fuel by the body. Lipid levels can be an important measure of health; for example, a person who has high cholesterol has an increased risk of heart disease and stroke.
Lipids are found in the bloodstream or stored in tissues. They are an important part of cell structure and other biological functions in the body.
Last Updated: May 25, 2007
Author: Jeannette Curtis,
Caroline Rea, RN, BS, MS
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Atherosclerosis 
Atherosclerosis, sometimes called “hardening of the arteries,” occurs when cholesterol, calcium, and other substances build up in the inner lining of the arteries, forming a material called plaque. Over time, plaque buildup narrows the artery and blocks blood flow through it.
Last Updated: May 29, 2008
Medical Review: Caroline S. Rhoads, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
Ruth Schneider, MPH, RD - Diet and Nutrition Atherosclerosis, sometimes called “hardening of the arteries,” occurs when fat (cholesterol) and calcium build up in the inner lining of the arteries, forming a substance called plaque. Over time, the fat and calcium buildup narrows the artery and blocks blood flow through it.
- When atherosclerosis affects the arteries that supply blood to the heart, it can restrict blood flow to the heart muscle, causing heart pain (angina), irregular heartbeats (arrhythmia), and other problems. Plaque may burst open the artery lining, causing blood clots that can block blood flow, which in turn may cause a heart attack and cause damage to the heart muscle. Atherosclerosis in the heart (coronary) arteries is called coronary artery disease.
- When atherosclerosis affects the arteries that supply blood to the brain, it may cause a transient ischemic attack (TIA) or stroke.
- Atherosclerosis can affect arteries in other parts of the body, such as the pelvis and legs, causing poor circulation, slower healing of skin injuries, and erection problems.
A major part of treating atherosclerosis and coronary artery disease involves lifestyle changes (such as quitting smoking) and medications to help reduce high cholesterol, control high blood pressure, and manage other factors that increase a person's risk of heart attack, stroke, and other complications.
Last Updated: May 29, 2008
Author: Robin Parks, MS
Medical Review: Caroline S. Rhoads, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
Ruth Schneider, MPH, RD - Diet and Nutrition
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Heart attack content provided by Healthwise
A heart attack—also called myocardial infarction or MI—occurs when an area of heart muscle is completely deprived of blood, and the heart muscle cells die.
A heart attack may result when plaque inside the heart arteries breaks open or ruptures, forming a clot that significantly blocks blood flow through the artery.
A plaque is made up of cholesterol, white blood cells, calcium, and other components, and it is surrounded by a fibrous cap. This fibrous cap may tear or rupture if blood suddenly flows faster, or the artery suddenly narrows. A tear or rupture signals the body to repair the injured artery lining, much as it might heal a cut on the skin, by forming a blood clot to seal the area. A blood clot that forms in an artery can completely block blood flow to the heart muscle and cause a heart attack.
The pain of a heart attack often occurs with other symptoms, including:
- Chest discomfort or pain that may be crushing or squeezing or may feel like a heavy weight on the chest.
- Chest discomfort or pain that occurs with:
o Sweating.
o Shortness of breath.
o Nausea or vomiting.
o Pain that spreads from the chest to the neck, the jaw, or one or both shoulders or arms.
o Dizziness or lightheadedness.
o A fast or irregular heartbeat.
o Loss of consciousness.
The pain of a heart attack usually will not go away with rest.
It is important to recognize the early stages of a heart attack and to seek emergency care. Medical treatment is needed to prevent death. Sometimes medicines can be given to reduce the damage to the heart muscle caused by a heart attack.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Stroke
content provided by Healthwise A stroke is a sudden disruption in blood flow to the brain caused by a blockage or bleeding of a blood vessel. Areas of the brain that are affected by the blockage or bleeding can become damaged within minutes.
The effects of a stroke may be mild or severe and temporary or permanent, depending on which brain cells are damaged, how much of the brain is involved, and how quickly the blood supply is restored to the area.
Symptoms of a stroke are sudden and may include:
Numbness, weakness, or lack of movement (paralysis) in the face, an arm, or a leg, especially on only one side of the body.
Trouble seeing in one or both eyes.
Confusion and difficulty speaking.
Dizziness and a loss of balance or coordination.
Vomiting.
A sudden, severe headache.
A person with stroke symptoms needs immediate medical attention to help limit potential damage. Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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LDL (low-density lipoprotein) cholesterol
content provided by Healthwise LDL (low-density lipoprotein) cholesterol is "bad" cholesterol, which carries mostly fat and only a small amount of protein from the liver to other parts of the body. A high LDL cholesterol level is considered a risk factor for coronary artery disease (CAD) because, under certain conditions, it can cause hardening of the arteries (atherosclerosis).
Cholesterol is measured either in milligrams per deciliter of blood (mg/dL) or in millimoles per liter of blood (mmol/L).
- An LDL cholesterol level of less than 100 mg/dL (less than 2.6 mmol/L) is considered optimal.
- 100 to 129 (2.6 to 3.35) is considered near optimal.
- 130 to 159 (3.35 to 4.10) is considered borderline high.
- 160 to 189 (4.12 to 4.88) is considered high.
- 190 and above (4.90 to 4.88) is considered very high.
People who have at least a moderate risk for developing heart disease (especially those who have diabetes) may benefit from lowering their LDL cholesterol levels. The specific target LDL level depends on a person's number and type of risk factors.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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HDL (high-density lipoprotein) cholesterol
content provided by Healthwise HDL (high-density lipoprotein) is sometimes called "good" cholesterol because it helps prevent cholesterol from building up in the arteries. HDL, which is made mostly of protein and only a small amount of fat, helps clear LDL (low-density lipoprotein), or “bad,” cholesterol from the body.
High levels of HDL appear to help protect against heart disease. A person who is at risk for heart disease may be advised to raise his or her HDL levels by eating a balanced diet, exercising and losing weight, and stopping tobacco use. In addition, medicines may be used to raise HDL levels.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Triglycerides
content provided by Healthwise Triglycerides are a type of fat that is found in the blood. They are the most common type of fat and are a major source of energy.
When a person eats, his or her body uses the calories it needs for quick energy. It converts excess calories into triglycerides and stores them in fat cells to use later. In normal amounts, triglycerides are very important to good health. But having high triglyceride levels may increase a person's risk of developing coronary artery disease (CAD). Very high triglycerides may lead to pancreatitis in certain people.
Triglyceride levels are categorized as follows:
- Below 150 milligrams per deciliter (mg/dL) is considered normal.
- 150 to 199 is borderline-high.
- 200 to 499 is high.
- 500 or higher is very high.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Interactive Tool: Are You at Risk for a Heart Attack?
content provided by Healthwise What does this tool measure?
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Click here to find your risk of heart attack.
This interactive tool measures your chance of having a heart attack in the next 10 years. The tool uses the values you enter to calculate your risk score. The calculation is based on information from the Framingham Heart Study. During the past 50 years, the Framingham Heart Study has studied the progression of heart disease and its risk factors. |
The values you enter include the most important risk factors for heart disease. They are as follows:
- Age and gender. The number of people affected by heart disease increases with age in men after age 45 and in women after age 55.
- Smoker. Select "yes" if you have smoked any cigarettes in the past month. Quitting smoking may be the most important step you can take to reduce your risk.
Systolic blood pressure.
- Systolic blood pressure is the first number of your blood pressure reading. For example, if your reading is 120/80 (120 over 80), your systolic blood pressure is 120.
- Blood pressure medicine. Medicines used to treat high blood pressure include diuretics, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), beta-blockers, calcium channel blockers, and direct renin inhibitors. Enter "yes" if you take one of these medicines.
- HDL cholesterol. HDL, or high-density lipoprotein, is the "good" cholesterol because it helps prevent cholesterol from building up in your arteries. The higher your HDL, the better. An HDL of 60 mg/dL and above protects against heart disease. An HDL of less than 40 mg/dL puts you at major risk of heart attack.
- Total cholesterol. Total cholesterol is the sum of all the cholesterol in your blood. The higher your total cholesterol, the greater your risk for heart disease. A total cholesterol of 240 mg/dL and above puts you at twice the risk of heart disease compared with someone whose cholesterol is below 200 mg/dL. Less than 200 mg/dL gives you a lower risk for heart disease.
Last Updated: November 24, 2006
Author: Douglas Dana
Kathe Gallagher, MSW
Medical Review: Caroline S. Rhoads, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
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Hypothyroidism
content provided by Healthwise Hypothyroidism is a condition in which the thyroid gland does not produce enough thyroid hormone, which regulates the way the body uses energy.
A low thyroid level can cause symptoms of fatigue, weakness, lethargy, weight gain, depression, memory problems, constipation, dry skin, intolerance to cold, coarse and thinning hair, brittle nails, or a yellowish tint to the skin.
Hypothyroidism usually develops slowly. It often results from a problem in which the body's own natural defense (immune) system attacks the thyroid gland (autoimmune thyroiditis or Hashimoto's thyroiditis). Hypothyroidism may also develop following radiation treatment or surgical removal of the thyroid.
Hypothyroidism is treated with medications to replace the thyroid hormone. Symptoms usually disappear within a few months after treatment begins, but most people need to continue taking thyroid hormones for life.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Menopause
content provided by Healthwise Menopause is the milestone in every woman's life that marks the end of her reproductive years. It is the point in time when a woman has had no menstrual periods for 1 year, which happens when the ovaries have stopped producing enough estrogen and progesterone to keep the menstrual cycle going.
Menopause marks the end of the perimenopausal phase and the beginning of the postmenopausal phase. While the average age of menopause is around 50, every woman's body has its own unique timeline. Some women stop having periods (menstruating) in their mid-40s, while others continue until their mid-50s.
After menopause, a woman's estrogen stabilizes at a low level. Although low estrogen helps reduce the risk of some types of cancer, it does lead to an increasing loss in bone density, which sometimes causes osteoporosis.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Lipid disorders
content provided by Healthwise Lipid disorders are problems that affect the way cholesterol is produced, used, carried in the blood, or disposed of by the body. People with lipid disorders develop very high total cholesterol levels, very low HDL (or “good”) cholesterol levels, and/or high triglyceride levels.
Lipid disorders are often inherited. People who have lipid disorders are usually at risk of developing coronary artery disease, often at an early age.
If a person is known to have a lipid disorder, treatment can be started early to lower the person's cholesterol, and family members can be made aware that they may also be at risk.
Examples of inherited lipid disorders include familial combined hyperlipidemia and familial hypercholesterolemia.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Therapeutic Lifestyle Changes (TLC) diet
content provided by Healthwise
The Therapeutic Lifestyle Changes (TLC) diet is a way to eat that lowers cholesterol. It is low in saturated fat and cholesterol, which can reduce blood cholesterol levels and lower the risk of heart problems.
The TLC diet calls for:
- Less than 7% of daily calories from saturated fat.
- No more than 200 mg of dietary cholesterol a day.
- 25% to 35% of daily calories from fat, mainly from unsaturated fat. Most of the fat should be monounsaturated, and only 10% should be polyunsaturated fat.
- Only 2,400 mg of sodium a day.
- Just enough calories to maintain a healthy weight and avoid weight gain.
The TLC diet is part of the Therapeutic Lifestyle Changes program, which aims to lower cholesterol through diet, exercise, weight loss if needed, and other changes, such as quitting smoking. It is recommended by the National Cholesterol Education Program of the U.S. National Institutes of Health.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine
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Statins
content provided by Healthwise
Statins are a type of medicine used to treat high cholesterol. These medicines block an enzyme the body needs to produce cholesterol, thereby lowering the total amount of it in the blood.
Statins, also known as HMG-CoA reductase inhibitors, help reduce the risk of heart attack and stroke. Along with reducing cholesterol levels in the blood, statins reduce inflammation around the cholesterol buildup (called a plaque). By stabilizing the plaque, there is less risk that it will rupture and cause a blood clot that can lead to a heart attack or stroke.
Last Updated: May 25, 2007
Author: Jeannette Curtis
Caroline Rea, RN, BS, MS
Medical Review: Patrice Burgess, MD - Family Medicine
Adam Husney, MD - Family Medicine
Kathleen Romito, MD - Family Medicine ↑ Back
Lipoproteins and cholesterol
content provided by Healthwise Roles of lipoproteins and triglycerides
| Type |
What they do |
| Low-density lipoproteins (LDL) |
- Deliver cholesterol to your body
- In excess, lead to a buildup of cholesterol in the walls of your arteries
|
| High-density lipoproteins (HDL) |
- Prevent harmful buildup of cholesterol in your arteries
|
| Triglycerides |
- Affect production of cholesterol-rich lipoproteins that cause high cholesterol
- Store fat nutrients
- Increase the ability of blood to clot
|
| Chylomicrons |
- Carry dietary fat from the intestine to the liver
- Deliver dietary fat in the form of triglyceride to muscle tissue cells
- Deposit excess triglyceride in fat (adipose) tissue
|
| Very low-density lipoproteins (VLDL) |
- Distribute triglyceride made in the liver to muscle cells
- Deposit excess triglyceride in the fat tissue
- In excess, can contribute to buildup of cholesterol in your arteries
|
"Bad" cholesterol: Low-density lipoprotein (LDL) contains a smaller proportion of protein than other lipoproteins. LDL consists mostly of cholesterol (75%), and the majority of the cholesterol circulating in your blood (60% to 75%) is found in LDL. As a result, LDL accounts for the majority of the cholesterol in your total cholesterol measurement.
A certain level of LDL in your blood is normal and healthy because LDL is responsible for delivering cholesterol to the parts of your body that need it. Excess LDL, however, causes a buildup of cholesterol in the walls of your arteries, contributing to the development of atherosclerosis.
"Good" cholesterol: High-density lipoprotein (HDL) contains a much larger proportion of protein than LDL does. HDL carries about 20% to 30% of the cholesterol in your blood. Unlike LDL, the job of HDL is to remove excess cholesterol from your cells and the walls of your arteries and then transport the cholesterol back to your liver for disposal. While HDL has other roles, not all of which are fully understood, you can think of HDL as a positive force in the entire lipoprotein cycle. Overall, HDL is "good" because it may actually slow or even reverse the development of atherosclerosis.
Triglycerides: Triglycerides combine with cholesterol and protein to make lipoproteins. Your body uses and stores fat nutrients as triglyceride. In addition to processing triglyceride from dietary fat, your body also produces triglyceride in your liver.
The way your body processes triglyceride-rich lipoproteins, such as chylomicrons and VLDL, directly affects the making of cholesterol-rich lipoproteins that cause high cholesterol, such as LDL. For example, when there are high levels of triglyceride to be processed because of a diet high in saturated fat, the body produces more LDL. This helps to explain why a diet high in saturated fat can significantly increase your LDL level, your total cholesterol, and your risk of atherosclerosis.
Chylomicrons: When you eat foods that contain fat, enzymes in your small intestine break them down into small particles of triglyceride. Your small intestine then absorbs these particles and combines them with small amounts of cholesterol, protein, and phospholipid to form lipoproteins called chylomicrons. The chylomicrons circulate in the bloodstream and deliver triglycerides to your cells for immediate use or for storage.
Very low-density lipoprotein (VLDL): These lipoproteins are "very low-density" because they contain very little protein. VLDL is composed largely of triglyceride but also carries 10% to 15% of the cholesterol in your blood. The main purpose of VLDL is to distribute the triglyceride produced by your liver.
Last Updated: July 11, 2008
Author: Robin Parks, MS
Medical Review: E. Gregory Thompson, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
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Complications of atherosclerosis
content provided by Healthwise The link between high cholesterol and the complications of atherosclerosis is similar to the link between smoking and lung cancer. Although smoking does not guarantee that you will develop lung cancer, it dramatically increases your chances. The same is true of high cholesterol and atherosclerosis.
Atherosclerosis can develop in any of your arteries, including those that supply blood to your heart muscle, your brain, and your arms and legs. Each of the potential complications of atherosclerosis is associated with arteries in a different part of your body. The following table summarizes the effects that three important complications of atherosclerosis can have on your health.
Complications of atherosclerosis
| Complication |
Artery affected |
How it can affect your health |
| Coronary artery disease (CAD) |
Coronary arteries, which supply the heart |
- Chest pain (angina)
- Heart attack (myocardial infarction)
- Sudden death
|
| Peripheral arterial disease (PAD) |
Large arteries that supply the arms and legs |
- Decreased blood circulation to your arms and legs
- Weakness or pain in arms or legs
- Paleness or blue tinge to your skin
- Loss of hair in affected areas
- Ulcers or loss of limb
|
| Cerebrovascular disease |
Carotid and cerebral arteries, which supply the brain |
- Failure of the brain to receive oxygenated blood
- Stroke
|
Last Updated: July 11, 2008
Author: Robin Parks, MS
Medical Review: E. Gregory Thompson, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology
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Stages of atherosclerosis
content provided by Healthwise Although the exact biological process is not completely understood, scientists have described three different stages of atherosclerosis that lead to the "clogging" of your arteries.
- The fatty streak: The first evidence of atherosclerosis can be found in children 10 to 14 years of age. The "fatty streak" appears as a yellow streak running along the major arteries, such as the aorta. The streak consists of smooth muscle cells, which are filled with cholesterol, and macrophages (a type of immune system "scavenger" cell that removes harmful substances, such as excess cholesterol particles, from the bloodstream). The fatty streak alone does not cause any symptoms but, over time, can develop into a more advanced form of atherosclerosis called fibrous plaque.
Fibrous plaque: A fibrous plaque forms in the inner layer of the artery. The plaque consists of large numbers of smooth muscle cells, macrophages, and lymphocytes (a type of white blood cell that typically responds to an infection or injury). These cells are all filled with cholesterol. As the fibrous plaque grows, it projects into the space inside the artery where the blood is flowing.
- Complicated lesion: The last stage of atherosclerosis occurs when the fibrous plaque breaks open, exposing the cholesterol and connective tissue underneath. This rupture provokes a strong clotting reaction from your blood, such as when you have a cut. The combination of fibrous plaque and the blood clot is called a complicated lesion.
What does atherosclerosis do to my arteries?
- It narrows your arteries. When the fibrous plaque grows large enough, it begins to narrow your arteries. This narrowing process happens slowly over many years. In time, the plaque growing into your arteries can limit blood flow to such a degree that parts of your body that depend on the arteries for blood begin to suffer from lack of oxygen, a condition called ischemia. When fibrous plaque in your coronary arteries causes your heart muscle to suffer from lack of oxygen, you may experience chest pain (angina).
- It hardens your arteries. When hard plaque forms in the walls of an artery, it can restrict the artery's ability to widen (dilate) so that more blood can flow through when needed, such as when you physically exert yourself. This "hardening" of your coronary arteries can also cause chest pain, usually during exertion.
- It blocks your arteries. When a blood clot forms around a crack or rupture in the fibrous plaque, this complicated lesion can completely block the flow of blood through the artery. Such an abrupt loss of blood supply causes lack of oxygen to or actual death of tissue (infarction), which can then damage tissues or organs that normally receive blood from that artery. Men who smoke and/or have high cholesterol have a greater chance of having a plaque rupture, causing a heart attack or sudden death.
The role of smoking
Smoking plays a large role in the development of atherosclerosis. The carbon monoxide and nicotine contained in tobacco smoke affect blood flow through your arteries by:
- Making it easier for cholesterol-carrying lipoproteins to enter the walls of your arteries.
- Promoting the formation of fibrous plaque.
- Promoting the formation of blood clots that can completely block your arteries.
Reversing atherosclerosis
If you think of atherosclerosis as a response to injury, the buildup of fibrous plaque can be reversed by removing the source of injury. In the case of high cholesterol, by reducing the amount of LDL cholesterol in your arteries and increasing the amount of HDL, which removes cholesterol that is already in your artery walls, you can actually reverse atherosclerosis. The ability to reverse atherosclerosis helps explain why treating high cholesterol can reduce the risk of further complications from atherosclerosis. Last Updated: July 11, 2008
Author: Robin Parks, MS
Medical Review: E. Gregory Thompson, MD - Internal Medicine
Robert A. Kloner, MD, PhD - Cardiology ↑ Back
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