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Lowering Your Cholesterol

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Medical Author:

Benjamin Wedro, MD, FACEP, FAAEM

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Cholesterol facts

• High cholesterol is also referred to as hypercholesterolemia (hyper=high + cholesterol + emia = in the blood) or hyperlipidemia
• Cholesterol is a fatty substance that is an important part of the outer lining of cells in the body of animals.
• Cholesterol is also found in the blood circulation of humans.
• Cholesterol in the blood originates from dietary intake and liver production.
• Dietary cholesterol comes primarily from animal sources including meat, poultry, fish, and dairy products.
• Organ meats such as liver, are especially high in cholesterol content.
• LDL (low density lipoprotein) cholesterol is called "bad" cholesterol, because elevated levels of LDL cholesterol are associated with an increased risk of coronary heart disease.
• HDL (high density lipoprotein) cholesterol is called the "good cholesterol" because HDL cholesterol particles prevent atherosclerosis by extracting cholesterol from artery walls and disposing of them through liver metabolism.
• High levels of LDL cholesterol and low levels of HDL cholesterol are risk factors for atherosclerosis.
• Research has shown that lowering LDL cholesterol reduces the risk of heart attacks, strokes, and peripheral artery disease.
• The National Institute of Health, the American Heart Association and the American College of Cardiology publish guidelines to help physicians and patients with this risk reduction for heart attack and stroke.
• Factors that affect blood cholesterol levels include diet, body weight, exercise, age and gender, diabetes, heredity, and other causes including underlying medical conditions.
• Guidelines recommend that cholesterol screening occur every 5 years after age 20. Should elevated cholesterol levels be found, testing may need to occur more frequently.
• Health care practitioners and the National Institute of Health recommend that a person's cholesterol level stay below 200.
• Cholesterol levels 200-239 are considered borderline high.
• Cholesterol levels 240 or greater are considered high.
• Drugs available to treat high cholesterol include statins, bile acid resins, and fibric acid derivatives.
• Drugs to lower blood cholesterol levels are most effective when combined with a low cholesterol diet.

What is cholesterol?

Cholesterol is a chemical compound that is naturally produced by the body and is structurally a combination of lipid (fat) and steroid. Cholesterol is a building block for cell membranes and for hormones like estrogen and testosterone. About 80% of the body's cholesterol is produced by the liver, while the rest comes from our diet. The main sources of dietary cholesterol are meat, poultry, fish, and dairy products. Organ meats, such as liver, are especially high in cholesterol content, while foods of plant origin contain no cholesterol. After a meal, dietary cholesterol is absorbed from the intestine and stored in the liver. The liver is able to regulate cholesterol levels in the blood stream and can secrete cholesterol if it is needed by the body.

What are LDL and HDL cholesterol?

LDL cholesterol is called "bad" cholesterol, because elevated levels of LDL cholesterol are associated with an increased risk of coronary heart disease, stroke, and peripheral artery disease. LDL lipoprotein deposits cholesterol along the inside of artery walls, causing the formation of a hard, thick substance called cholesterol plaque. Over time, cholesterol plaque causes thickening of the artery walls and narrowing of the arteries, a process called atherosclerosis, which decreases blood flow through the narrowed area.

HDL cholesterol is called the "good cholesterol" because HDL cholesterol particles prevent atherosclerosis by extracting cholesterol from the artery walls and disposing of them through the liver. Thus, high levels of LDL cholesterol and low levels of HDL cholesterol (high LDL/HDL ratios) are risk factors for atherosclerosis, while low levels of LDL cholesterol and high levels of HDL cholesterol (low LDL/HDL ratios) are desirable and protect against heart disease and stroke.

Total cholesterol is the sum of LDL (low density) cholesterol, HDL (high density) cholesterol, VLDL (very low density) cholesterol, and IDL (intermediate density) cholesterol.