What does the liver do?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 2, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

The liver plays a crucial role in maintaining the body's overall health by performing various essential functions, including detoxification, metabolism, production of bile and proteins, and storage of vitamins and minerals. These functions are vital for maintaining proper bodily functions, and any disruption in liver function can lead to severe morbidity and mortality. The liver's ability to detoxify harmful substances, such as toxins and alcohol, is essential for preventing damage to the body's cells and tissues 1. Some of the key functions of the liver include:

  • Processing nutrients from food and removing toxins from the blood
  • Producing proteins necessary for blood clotting and storing vitamins and minerals
  • Regulating metabolism and maintaining proper blood sugar levels
  • Producing bile to aid in digestion and breaking down fats
  • Metabolizing medications and alcohol to remove them from the bloodstream The liver's unique structure, composed of specialized cells called hepatocytes, allows it to perform these complex functions and maintain the body's metabolic balance and overall health 1. In the context of alcoholic liver disease, the liver's functions can be severely impaired, leading to complications such as steatosis, lobular inflammation, and fibrosis or cirrhosis 1. Therefore, it is essential to prioritize liver health and take measures to prevent liver damage, such as avoiding excessive alcohol consumption and maintaining a healthy diet.

From the FDA Drug Label

After absorption, ursodiol enters the portal vein and undergoes efficient extraction from portal blood by the liver (i.e., there is a large “first-pass” effect) where it is conjugated with either glycine or taurine and is then secreted into the hepatic bile ducts. The sites of the drug’s therapeutic actions are in the liver, bile, and gut lumen. Reabsorbed free ursodiol is reconjugated by the liver Eighty percent of lithocholic acid formed in the small bowel is excreted in the feces, but the 20% that is absorbed is sulfated at the 3-hydroxyl group in the liver to relatively insoluble lithocholyl conjugates which are excreted into bile and lost in feces. Absorbed 7-keto-lithocholic acid is stereospecifically reduced in the liver to chenodiol Ursodiol suppresses hepatic synthesis and secretion of cholesterol, and also inhibits intestinal absorption of cholesterol

The liver conjugates ursodiol with glycine or taurine, secretes it into the hepatic bile ducts, reconjugates reabsorbed free ursodiol, sulfates lithocholic acid, reduces 7-keto-lithocholic acid to chenodiol, and suppresses hepatic synthesis and secretion of cholesterol. 2

From the Research

Liver Functions

The liver is a critical organ that performs numerous physiological processes, including:

  • Macronutrient metabolism, such as processing, partitioning, and metabolism of macronutrients to provide energy 3
  • Blood volume regulation
  • Immune system support
  • Endocrine control of growth signaling pathways
  • Lipid and cholesterol homeostasis
  • Breakdown of xenobiotic compounds, including many current drugs

Macronutrient Metabolism

The liver plays a crucial role in macronutrient metabolism, including:

  • Storing glucose in the form of glycogen with feeding 3
  • Assembling glucose via the gluconeogenic pathway in response to fasting 3
  • Oxidizing lipids and packaging excess lipid for secretion to and storage in other tissues, such as adipose 3
  • Handling protein and amino acid metabolism, including the majority of proteins secreted in the blood and the processing of amino acids for energy 3

Liver Health and Disease

The liver is also involved in various diseases, including:

  • Non-alcoholic fatty liver disease (NAFLD) 4, 5
  • Alcoholic liver disease 4
  • Autoimmune hepatitis 4
  • Viral hepatitis 4, 6
  • Liver failure, which can result from various sources, such as viral infection, overnutrition, or oncologic burden 3

Treatment and Management

Various treatments and management strategies are available for liver diseases, including:

  • Ursodeoxycholic acid (UDCA) for non-cholestatic liver diseases 4, 5
  • Tenofovir and entecavir for treating patients with hepatitis B virus-related acute on chronic liver failure 6
  • Nutrition and dietary management to support liver health and prevent disease 7

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

The liver.

Current biology : CB, 2017

Research

Ursodeoxycholic Acid in Treatment of Non-cholestatic Liver Diseases: A Systematic Review.

Journal of clinical and translational hepatology, 2016

Research

Nutrition and Liver Health.

Digestive diseases (Basel, Switzerland), 2017

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.