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Pronunciation:  ku'lestu`rowl

WordNet Dictionary
[n]  an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues

CHOLESTEROL is a 11 letter word that starts with C.


 Synonyms: cholesterin
 See Also: HDL cholesterol, LDL cholesterol, steroid alcohol, sterol



Medical Dictionary
 Definition: A fat-like substance found in blood, muscle, liver, brain, and other tissues in people and animals. The body makes and needs some cholesterol. Too much cholesterol, however, may cause fat to build up in the artery walls and cause a disease that slows or stops the flow of blood. Butter and egg yolks are foods that have a lot of cholesterol.
Biology Dictionary
  1. A lipid which higher organisms use in the construction of cell membranes and as a precursor molecule in steroid synthesis. If a person produces too much cholesterol, the excess often gets laid down on the interior of blood vessels as plaque, causing heart disease, hardening of the arteries, and often heart attacks or strokes.

    Cholesterol is carried through the bloodstream in molecules called lipoproteins. There are two major types: low density lipoproteins (LDLs, also known as "bad" cholesterol) and high density lipoproteins (HDLs, aka "good" cholesterol).

    When your doctor measures your cholesterol, he takes readings of the different types of cholesterol in your blood:

    Total Cholesterol

    • Desirable: less than 200 mg/dl
    • Borderline High: 200-239 mg/dl
    • High: more than 240 mg/dl
    • Cholesterol is absorbed from the instestine and contained in chylomicron which brings the cholestrol to the liver. Some cholesterol is synthesized by the liver. Cholesterol is the precursor of steroid hormones and constituent of cell membranes. Some cholesterol is excreted in the bile. The rest of cholesterol is carried in blood by lipoproteins.

      Lipoproteins in serum are classified according to their density. High-density lipoproteins (HDL), low-density lipoproteins (LDL), and very low density lipoproteins (VLDL). Each fraction contains cholesterol. It is the proportion of cholesterol in these fractions of lipoprotein that is associated with the risk of atherosclerotic heart disease (ASHD): the higher the level of LDL cholesterol, the greater the risk of ASHD, and the higher the level of HDL cholesterol, the lower the risk of ASHD.

      Lowering the serum cholesterol level in patients without cardiac disease do not reduce mortality rate. Lowering the cholesterol level in cardiac patients clearly reduces mortality. This reduction of risk is proportional to the reduction in LDL cholesterol and the increase in HDL cholesterol.

      Normal ranges for serum cholesterol are 1.2 - 6.5 mmol/L