What is cholesterol?

Heartistry Online ToolCholesterol is:

  • A soft, waxy, fatty substance that is a part of all cell membranes and many hormones
  • Needed for rapid conduction of nerve impulses, and for several other body functions.
  • Produced by the body, primarily in the liver.

Some cholesterol comes from our diet, often contributing to "high cholesterol," meaning there is too much cholesterol in the blood stream. High blood cholesterol:

  • Is a risk factor for heart disease and stroke.
  • Has no symptoms.
  • Contributes to the formation of fatty plaques on the inside of artery walls.
  • The plaques narrow the inside diameter of the blood vessel, reducing blood flow.
  • Reduced blood flow can cause "angina pectoris," or chest pain because the heart muscle is not getting enough oxygen.
  • If the plaque ruptures, a clot forms. A clot in an artery in the heart can cause a heart attack; a clot in an artery in the brain can cause a stroke. The bigger the artery and the bigger the clot, the more severe the heart attack or stroke.

Cholesterol travels in the blood stream attached to lipoproteins, clusters of proteins linked together. The two most commonly looked at lipoproteins are low-density lipoproteins (LDL) and high-density lipoproteins (HDL). A blood test called a lipid profile reports the total cholesterol level as well as LDL, HDL, and triglyceride levels. Results are measured in milligrams (mg) of total cholesterol, LDL, HDL or triglycerides per deciliter (dl) of blood. A lipid profile is usually done after a nine to twelve hour fast.

It is important to know your numbers, so you know what your risks are. If the levels are all where they should be, try to keep them there. If one or more of them are too high or too low it is called dyslipidemia. There are multiple methods to treat dyslipidemias, or "problem blood lipids." The most common are diet, exercise, and medications. Other things that can affect lipid levels are smoking, sleep, and stress. Learning how to get and keep your lipids in a desirable range can be a challenging, rewarding, frustrating, or exhilarating experience, depending on your commitment and attitude about lifestyle changes that may be recommended.