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.
Charles Patrick Davis, MD, PhD
Dr. Charles "Pat" Davis, MD, PhD, is a board certified Emergency Medicine doctor who currently practices as a consultant and staff member for hospitals. He has a PhD in Microbiology (UT at Austin), and the MD (Univ. Texas Medical Branch, Galveston). He is a Clinical Professor (retired) in the Division of Emergency Medicine, UT Health Science Center at San Antonio, and has been the Chief of Emergency Medicine at UT Medical Branch and at UTHSCSA with over 250 publications.
- What is cholesterol?
- What are the different types of cholesterol?
- Why is high cholesterol dangerous?
- Where does cholesterol come from?
- What are normal cholesterol levels?
- Which foods can help lower cholesterol?
- What other lifestyle interventions help lower cholesterol?
- What medications are available to treat high cholesterol?
- High Cholesterol (Hyperlipidemia) FAQs
- Find a local Internist in your town
What is cholesterol?
Cholesterol is a chemical compound that the body requires as a building block for cell membranes and for hormones like estrogen and testosterone. The liver produces about 80% of the body's cholesterol and the rest comes from dietary sources like meat, poultry, eggs, fish, and dairy products. Foods derived from plants contain no cholesterol.
Cholesterol content in the bloodstream is regulated by the liver. After a meal, cholesterol in the diet is absorbed from the small intestine and metabolized and stored in the liver. As the body requires cholesterol, it may be secreted by the liver.
When too much cholesterol is present in the body, it can build up in deposits called plaque along the inside walls of arteries, causing them to narrow.
What are the different types of cholesterol?
Cholesterol does not travel freely through the bloodstream. Instead, it is attached or carried by lipoproteins (lipo = fat) in the blood. There are three types of lipoproteins that are categorized based upon how much protein there is in relation to the amount of cholesterol.
Low-density lipoproteins (LDL) contain a higher ratio of cholesterol to protein and are thought of as the “bad” cholesterol. Elevated levels of LDL lipoprotein increase the risk of heart disease, stroke, and peripheral artery disease, by helping form cholesterol plaque along the inside of artery walls. Over time, as plaque buildup (plaque deposits) increases, the artery narrows (atherosclerosis) and blood flow decreases. If the plaque ruptures, it can cause a blood clot to form that prevents any blood flow. This clot is the cause of a heart attack or myocardial infarction if the clot occurs in one of the coronary arteries in the heart.
High-density lipoproteins (HDL) are made up of a higher level of protein and a lower level of cholesterol. These tend to be thought of as “good” cholesterol. The higher the HDL to LDL ratio, the better it is for the individual because such ratios can potentially be protective against heart disease, stroke, and peripheral artery disease.
Very low-density lipoproteins (VLDL) contain even less protein than LDL. VLDL like LDL has been associated with plaque deposits.
Triglycerides (a type of fat) may increase cholesterol-containing plaques if levels of LDL are high and HDL are low.
Total cholesterol score is the sum of HDL cholesterol, LDL cholesterol and 20% of triglycerides as determined by a blood test. A high score indicates an increased risk for developing cardiovascular disease and/or strokes.
Chart courtesy of the National Institutes of Health.
Tips to keep it under control.