Cholesterol is a substance in animal tissue that is an essential component of cell membranes and nerve fiber insulation. Cholesterol is important for the metabolism and transport of fatty acids and in the production of hormones and Vitamin D.

Cholesterol is manufactured by the liver, and is also present in certain foods (e.g., eggs, shellfish). There are 2 types of cholesterol in the blood, high-density (HDL) and low-density (LDL) lipoproteins. Very low cholesterol levels may indicate malnutrition. It is fat-like substance that is made by the body and is found naturally in animal foods such as meat, fish, poultry, eggs, and dairy products. Foods high in cholesterol include liver and organ meats, egg yolks, and dairy fats. Cholesterol is carried in the blood. When cholesterol levels are too high, some of the cholesterol is deposited on the walls of the blood vessels. Over time, the deposits can build up causing the blood vessels to narrow and blood flow to decrease. The cholesterol in food, like saturated fat, tends to raise blood cholesterol, which increases the risk for heart disease.

Cholesterol is important lipid found only in animals. Cholesterol is important as cell membrane component, but also serves as a biosynthetic precursor for steroid hormones (e.g. sex hormones) and the active gall bladder ingredients bile acids (= detergents). The human liver can synthesize all the necessary levels of cholesterol and will reduce its own synthesis if cholesterol is taken in during a meal (only from animal sources). 'Bad' and 'Good' cholesterol refers to special transport particles of lipids in our blood serum called lipoprotein particles. The low density form or LDL is high in cholesterol and chronically high concentration of LDL in blood results in insoluble deposits that can clog arteries and restrict blood flow contributing to heart problems.

Cholesterol also stabilizes a cell against temperature changes. It is a major part of the membranes of the nervous system, the brain, the spinal cord and the peripheral nerves. In particular it is incorporated into the myelin sheath that insulates the nerves from the surrounding tissue. Cholesterol is also the forerunner of important hormones such as the female sex hormone, oestradiol, and the male sex hormone, testosterone, and of vitamin D, which we need in order to utilize calcium and form bone. Nearly all body tissues are capable of making cholesterol, but the liver and intestines make the most. We require cholesterol to produce the bile we need to digest the fats in our food, and the name itself comes from the Greek words for 'bile solids'.

Common Names: Cholesterol; Cholesterin
Chemical Name: Cholest-5-en-3ß-ol
Molecular formula: C27H46O
Molecular Weight: 386.6598
CAS Number: 57-88-5