The liver is the organ hardest hit by excessive drinking. When you drink, your liver metabolizes alcohol into acetaldehyde, which is highly toxic to cells and a potent carcinogen. Acetaldehyde is then metabolized into the less toxic acetate, which is then broken down into water and carbon dioxide. How fast alcohol is metabolized into acetaldehyde and then into acetate is determined by what enzymes you happen to have, which is genetic. If your liver metabolizes acetaldehyde slowly, you are likely to suffer more when you drink, but are also likely to drink less. Regardless of enzymes, the more you drink, the more damage you do to your liver.
The extent to which your liver can heal depends on how badly it is damaged. The first stage of alcohol induced liver damage is fatty liver disease. This happens when five to 10 percent of the liver’s weight is fat. The increased activity of alcohol metabolizing enzymes make it harder for your liver to metabolize fat, which therefore begins to accumulate. When you quit drinking, those enzymes return to normal levels, allowing your liver to metabolize fat normally and the condition resolves. The catch is that fatty liver disease typically has no symptoms, so you probably won’t know you have it unless it’s caught by accident.
The next stage of liver damage is alcoholic hepatitis. This typically does have symptoms that you would see a doctor about. Mild hepatitis might cause weight loss, abdominal pain, nausea, and vomiting. More severe symptoms include brain damage, kidney failure, jaundice, enlarged liver, abdominal swelling, fever, and spider angiomas, or swollen blood vessels. Alcoholic hepatitis may progress gradually, or it may come on suddenly after binge drinking. It is typically reversible unless it’s extremely severe.
Cirrhosis is the worst stage of alcoholic liver disease. Normally, the liver regenerates living tissue, but when cirrhosis occurs, damaged tissue is replaced with non-living scar tissue. This scar tissue doesn’t perform the necessary functions of the liver and may impede the living parts of the liver from functioning normally as well. It typically takes 10 years of heavy drinking to develop cirrhosis and about 10 to 20 percent of heavy drinkers develop the condition. Symptoms include accumulation of fluid in the abdomen, high blood pressure in the liver, bleeding in the esophagus, confusion, and enlarged spleen. In some cases, cirrhosis is reversible, but it often requires a liver transplant.
Whatever state your liver is in, it will absolutely improve if you quit drinking. Most people, those with fatty liver disease or mild alcoholic hepatitis, will recovery normal liver function in a matter of months, assuming continued abstinence and some healthy lifestyle changes. The liver is a resilient organ and typically does fine if you stop actively damaging it.