How the Liver Works

The liver is in the upper right part of the abdomen. Most of it is protected by the ribs. It is a vital organ that has many jobs. The liver:

• Makes bile, a substance that helps the body absorb fat.

• Makes proteins and blood-clotting factors that the body needs.

• Regulates glucose (sugar) in the blood and stores extra sugar.

• Works with the stomach and intestines to digest food.

• Stores vitamins and minerals.

• Removes toxic (poisonous) substances from the blood.

The Parts of the Liver and Nearby Organs

• Biliary tree: A network of tubes that carry bile out of the liver and into the duodenum.

• Bile ducts: Tubes between the liver and small intestine. Bile drains into them from the liver.

• Common bile duct: The duct from the liver (hepatic duct) and the duct from the gallbladder (cystic duct) meet to form the common bile duct. The common bile duct carries bile to the duodenum.

• Duodenum: The first part of the small intestine. When bile leaves the liver, it flows through the bile ducts into the duodenum. Here, bile starts mixing with food to help digestion.

• Gallbladder: An organ that stores bile.

• Spleen: An organ that filters blood. It also helps keep the body healthy and free of infection, as part of the immune system.

• Splenic vein: A blood vessel that carries blood from the spleen to the portal vein.

• Portal vein: A blood vessel that carries nutrient-rich blood from the digestive tract and spleen into the liver.

• Inferior vena cava: A large vein that carries blood from the liver, legs, and kidneys to the heart.

• Hepatic veins: Blood vessels that carry blood out of the liver to the inferior vena cava.

• Hepatic artery: A blood vessel that carries blood into the liver from the heart.

Blood Flows Through the Liver

All the blood that flows from the intestines, stomach, and spleen is filtered through the liver. The blood flows into the liver through the portal vein. It filters through the liver in a system of smaller and smaller veins. As blood passes over liver cells, these cells process nutrients in the blood. This processing makes products like proteins and sugars that can be used by the body. Blood is carried out of the liver through the hepatic vein to the heart.