The Effect of Bile on Cholesterol

While cholesterol is essential to normal body function, high blood cholesterol levels (hypercholesterolemia) constitute a health risk. Bile production is an important aspect of the regulation of cholesterol.

Cholesterol Structure

• Cholesterol is a very hydrophobic compound, which means that it lacks affinity for water and does not dissolve in blood. Unless it is removed from the blood, excess cholesterol can clog blood vessels, endangering your health.

Cholesterol Degradation

• The ring structure of cholesterol cannot be broken down to water and carbon dioxide. The elimination of excess cholesterol from the body therefore requires its conversion to bile acids and bile salts, as well as secretion into the bile. Bacteria also modify some of the cholesterol before excretion.

Bile Contents

• Bile consists of a watery mixture of organic (carbon-containing) and inorganic compounds. The main organic components of bile are phosphatidylcholine (lecithn) and bile salts (conjugated bile acids).

Bile Salts Synthesis and Function

• The liver uses cholesterol to synthesize bile acids in a multi-step process. Prior to secreting them into the bile, the liver converts bile acids into bile salts. Bile salts are more effective emulsifying agents (detergents) than bile acids, which help prepare cholesterol for degradation.

Bile Salts Circulation

• Of the 15 to 30 g of bile salts that the liver secretes daily, about 0.5 gram is made from cholesterol, to compensate for the amount lost in the feces. Promoting the excretion of bile acids with substances such as dietary fiber and certain drugs can increase bile salt production from cholesterol.

Significance

• Bile salts are not only a metabolic product of cholesterol, but they also constitute a solubilizer that facilitates cholesterol excretion in the bile. They contribute significantly to the removal of excess cholesterol from the bloodstream.