In Depth: Liver
The liver is the largest glandular organ in the body and performs multiple critical functions to keep the body pure of toxins and harmful substances.
An average adult liver weighs about three pounds. Located in the upper-right portion of the abdominal cavity under the diaphragm and to the right of the stomach, the liver consists of four lobes. It receives about 1.5 quarts of blood every minute via the hepatic artery and portal vein.
The liver is considered a gland—an organ that secretes chemicals—because it produces bile, a substance needed to digest fats. Bile’s salts break up fat into smaller pieces so it can be absorbed more easily in the small intestine.
In addition to producing bile, the liver:
- Detoxifies the blood to rid it of harmful substances such as alcohol and drugs
- Stores some vitamins and iron
- Stores the sugar glucose
- Converts stored sugar to functional sugar when the body’s sugar (glucose) levels fall below normal
- Breaks down hemoglobin as well as insulin and other hormones
- Converts ammonia to urea, which is vital in metabolism
- Destroys old red blood cells (called RBC’s)
The destruction of old red blood cells produces waste that gives fecal matter its usual brown color. Discoloration of stool — or darkened urine — could signal the onset of problems within the liver, such as viral hepatitis. Another common sign of liver problems is jaundice, the yellowing of the skin and eyes due to the buildup of bilirubin, a waste product of normal hemoglobin breakdown.
Common liver diseases include hepatitis infection, fatty liver disease, and cancer, as well as damage from alcohol, the pain reliever acetaminophen, and some cancer drugs.
Cirrhosis of the liver occurs when the organ becomes scarred and hardened so that it cannot function properly. This is most often caused by chronic liver disease brought on by long-term alcohol abuse or hepatitis C infection.
Liver dialysis—in which a machine performs the detoxification function of the liver—is still a relatively new treatment, and it cannot support a person longer than a few years. Dialysis is normally used in the time between liver failure and liver transplant surgery.