The liver produces a variety of substances: these include bile fluid, blood coagulation factors, and proteins such as fibrinogen and albumin. Cholesterol is synthesised by the liver in addition to ketones, which the body can use as an energy source, for example, during prolonged fasting.

The bile produced by the liver is particularly important for digestion. Bile is stored in the gall bladder, from which it is transported, if necessary, to the first section of the small intestine called duodenum. The bile breaks down and absorbs fats to facilitate the digestion of the enzymes secreted by the pancreas.

Function of the liver

Function	Examples
Preparation of bile fluid	Bile contributes to the breakdown of lipids (fats) in small intestine.
Detoxification	The modified substances pass through the gallbladder into the intestine.
Removing damaged red blood cells	Bilirubin pigment is made.
Storage	The liver stores glucose, blood, iron, as well as vitamins A and B12.
Energy release	Releases glucose when necessary.
Producing other substances	Albumin is a protein in the blood which binds water. Fibrinogen is needed for blood clotting. Cholesterol is needed for e.g. cell membranes.
Pathogen destruction	Destroying microbes and cell debris.