What does the liver do

The liver is a complex organ. It has lots of different function which are essential to live healthily.


The liver filters blood

It receives blood from two sources:

  • From the heart (via the hepatic artery)
  • From the intestine (via the portal vein)


The liver has an important role in the digestive system

Blood from the liver goes back to the heart through the hepatic vein.

The liver processes and stores nutrients from the blood to allow the body to use them. The blood entering the liver from the intestine contains fats, carbohydrates, vitamins and other nutrients.

Carbohydrates are broken down into sugars which provide energy. Any extra nutrients not needed straight away are stored in the liver for future use. These nutrients include glycogen (sugar), minerals like iron and vitamins such as vitamin A, B, D and K.


The liver makes lots of different substances

The liver produces lots of different substances that the body needs including:

  • Blood plasma proteins such as albumin, Albumin controls how much fluid is in each part of the body
  • Clotting factors which help to stop bleeding
  • Cholesterol
  • Vitamin D
  • Immune factors which help to fight infection
  • Some hormones
  • Bile



The liver produces bile which is a green/yellow liquid. Bile is formed from bilirubin, which comes from old red blood cells which have been broken down in the spleen. Bile helps the body to digest good by breaking fats down so they can be absorbed and enables the absorption of fat-soluble vitamins. Bile also helps the body get rid of waste products such as bilirubin and excess cholesterol which it passes out into the stool (poo).

After bile has been produced by the liver it is transported to the gall bladder where it is stored. When food is eaten the gall bladder releases bile through bile ducts into the small intestine to help with digestion and remove waste products.


The liver processes waste products

The liver gets ride of waste such as the breakdown products of old red blood cells, ammonia (which comes from proteins), medicines and drugs.