The Many Vital Functions of the Liver

The liver is the heaviest organ in the body and one of the largest. It's located in the upper right portion of your belly under the ribs and is responsible for functions vital to life. The liver primarily processes nutrients from food, makes bile, removes toxins from the body, and builds proteins. It metabolizes many drugs. It breaks down fat and produces cholesterol. It converts glycogen into glucose. It creates immune factors necessary to fight infection. It's easy to see how inflammation of the liver, or hepatitis, interferes with these important functions and can lead to poor health. Fortunately, the liver is extremely resilient and most cases of liver inflammation don't even come to medical attention, but in cases of the severe liver disease, there can be a serious interruption of these essential liver functions. Let's look at each of these functions a little closer.

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Processing Nutrients from Food

The digestive system immediately begins to break down the food that we eat into smaller and smaller pieces. Eventually, these nutrients will enter the blood and travel to the liver through the hepatic portal system, the major pathway that blood takes from the ​digestive system to the liver. The liver will then process these nutrients in different ways, depending on the body's needs. It usually stores some of the nutrients in a form that the body can use for quick energy. The rest will be used to make other important chemicals the body needs. When the liver is severely damaged, such as in liver failure, it can't continue to process nutrients from the blood that the body must have. Without aggressive medical care, the absence of these essential liver functions can result in signs of serious illness like brain damage and coma.

Making Bile

Bile is a thick, green-yellow fluid that the liver produces to help digest food, especially fat, as it passes from the stomach to the intestines. This fluid is made in the liver but is stored in a nearby sac called the gallbladder. When a person eats a meal heavy in fat, like a juicy steak, the body will use its store of bile to help break down the fats in the steak for digestion.

Removing Toxins From the Blood

All of the blood in the body will eventually pass through the liver. This is important because the liver needs to pull out any bad things in the blood, such as toxins, and remove them from the body. It metabolizes many drugs and alcohol and helps remove other toxins such as damaged cells, proteins and old hormones. The liver prepares all of these types of toxins to be removed from the body. However, when the liver is damaged, these toxins can't be removed and they start to accumulate creating problems.

Building Proteins

A protein is a complex chemical that is essential to living things, like plants, animals, and people. Proteins are everywhere in the body and need to be constantly produced to sustain life. The liver is in charge of building many kinds of proteins that the body uses every day. For instance, there are many proteins produced by the liver that are responsible for blood clotting. When the liver is damaged, sometimes the body isn't able to clot blood effectively. In mild cases, it just takes a long time for bleeding to stop. However, in severe cases, the blood wouldn't be able to clot. A simple cut on the skin would lead to continued bleeding (though not necessarily a dangerous amount), and possibly bruises.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Gastrointestinal Society: Canadian Society of Intestinal Research. The liver - An amazing organ.

  2. Centers for Disease Control and Prevention. What is viral hepatitis?

  3. Johns Hopkins Medicine. Liver: Anatomy and functions.

  4. National Institute of Diabetes and Digestive and Kidney Diseases. Your digestive system and how it works.

  5. American Liver Foundation. The progression of liver disease.

  6. Johns Hopkins Medicine. Biliary system anatomy and functions.

  7. Center for Liver Disease and Transplantation. The liver and its functions.

  8. Cleveland Clinic. Liver disease.

By Charles Daniel
 Charles Daniel, MPH, CHES is an infectious disease epidemiologist, specializing in hepatitis.