The liver and its function
Your liver is a large and complex organ. It weighs about 1.5kg and sits below your right lung, surrounded and protected from injury by the lower ribs on that side. The liver has two main lobes, right lobe and left lobe.
Your liver is critically important to your health. Everything you eat and drink is digested in the stomach and intestine, and then passed into the blood in your stomach and intestines and then through your liver. Other substances that enter your body, for example in an injection, are also passed to your blood and pass through the liver.
As blood passes through your liver, your liver operates as a "chemical factory" breaking down nutrients for use in the body, filtering toxins and processing waste so it can be eliminated in the urine or faeces.
The hepatic artery and the hepatic portal vein supply blood to the liver. Before reaching the liver, blood in the portal vein passes through the gut (digestive system) and collects nutrients that the gut breaks down from our food (carbohydrates, proteins, fats and vitamins). Nutrients are then taken to the liver. The liver turns carbohydrates into two forms of energy. One is instant energy (glucose) and the other is stored energy (glycogen). The liver can store nutrients such as glycogen and vitamins until the body needs them.
Your liver performs the following functions:
- metabolises the food you eat, breaking down fats, carbohydrates and proteins into nutrients your body can use
- stores vitamins, minerals and sugar, converting these items into usable nutrients that are delivered to the cells throughout your body as they are required
- makes many substances the body needs including proteins, substances that help blood to clot and cholesterol which is an important building block in cell walls
- produces bile which breaks down the fats in food so they can be absorbed; bile is stored in the gallbladder and is passed through the bile duct to the small intestines.
If the liver is not working properly harmful substances can build up and cause problems with the normal functions of the body.
However, the liver is very good at repairing itself and can function normally with only a small part of it in working order.
The liver and surrounding organs