The liver is the largest solid organ and the largest gland in the human body. ... Classed as part of the digestive system, the roles of the liver include detoxification, protein synthesis, and the production of chemicals that help digest food. ... This vital organ carries out more than 500 functions:

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The major functions of the liver include:

• Bile production and Fat metabolization: Bile helps the small intestine break down and absorb fats, cholesterol, and some vitamins. Bile consists of bile salts, cholesterol, bilirubin, electrolytes, and water. Bile breaks down fats and makes them easier to digest.

• Absorbing and metabolizing bilirubin: Bilirubin is formed by the breakdown of hemoglobin. The iron released from hemoglobin is stored in the liver or bone marrow and used to make the next generation of blood cells.

• Metabolizing carbohydrate and proteinss: Carbohydrates are stored in the liver, where they are broken down into glucose and siphoned into the bloodstream to maintain normal glucose levels. They are stored as glycogen and released whenever a quick burst of energy is needed. Bile helps break down proteins for digestion.

• Vitamin and mineral storage: The liver stores vitamins A, D, E, K, and B12. It keeps significant amounts of these vitamins stored. In some cases, several years' worth of vitamins is held as a backup. The liver stores iron from hemoglobin in the form of ferritin, ready to make new red blood cells. The liver also stores and releases copper.

• Detoxification (Filters the blood): The liver filters and removes compounds from the body, including hormones, such as estrogen and aldosterone, and compounds from outside the body, including alcohol and other drugs.

• Supporting blood clots: Vitamin K is necessary for the creation of certain coagulants that help clot the blood. Bile is essential for vitamin K absorption and is created in the liver. If the liver does not produce enough bile, clotting factors cannot be produced.

• Immunological function: The liver is part of the mononuclear phagocyte system. It contains high numbers of Kupffer cells that are involved in immune activity. These cells destroy any disease-causing agents that might enter the liver through the gut.

• Synthesis of angiotensinogen: This hormone raises blood pressure by narrowing the blood vessels when alerted by production of an enzyme called renin in the kidneys.