How Alcohol Causes Liver Damage The direct toxicity of alcohol to the liver cells is the main cause of the resulting liver cell damages, which leads to chronic liver diseases. Epidemiological studies found that incidence of cirrhotic liver diseases are closely related to alcohol consumption. In countries where the average consumption of alcohol per capital is over 10kg per year, the incidence rate of alcoholic liver diseases was quite high. Consumption of alcohol was found to be related to approximately one half to two-thirds of the cirrhotic conditions. In addition, sporadic and heavy binge drinking was found to cause more damage than moderate drinking on a regular basis. Acute hepatitis can often occur if a chronic drinker has an extremely large amount of alcohol. Liver failure can also occur in some rare cases. If a normal person drinks an unusually large amount of alcohol within a short period of time, the triglyceride in the liver can dramatically increase five to 10 times and cause fatty liver deposits. When the alcohol enters the body, 95% of it will be metabolized in the liver. Inside the liver cells, alcohol turns to acetaldehyde, which is even more toxic to the liver than the original form of alcohol. The alcohol and its metabolites cause the liver to become inflamed. Long-term drinking causes the inflammation to become persistent and leads to fibrosis and cirrhosis. In the cirrhotic stage, many complications can happen and may even cause liver failure and death. Acetaldehyde can combine with the liver cell membrane to form a new antigen, which stimulates the immune system to produce autoimmune reactions. The metabolism of alcohol can also cause unusually high consumption of the oxygen, which becomes a metabolism disorder of the liver. This in turn causes fat deposits, degeneration, and necrosis of liver cells. The onset of inflammation leads to an over-production of free radicals that can further damage liver cells and impair their functions. Alcohol also reduces the production of antioxidants, which are the body's natural defenses against free radicals. If a patient is already infected with HBV or HCV, these harmful effects will exacerbate the present liver inflammation and progression of fibrosis can be accelerated dramatically. On top of exacerbating inflammation, acetaldehyde itself can also cause fibrosis directly. One of the mechanisms that alcohol promotes disease progression is by increasing the amount of certain cytokines, such as TGFb1 (transforming growth factor-beta 1), PDGF (platelet delivered growth factor), and PAI (Plasminogen activator inhibitor). They activate the hepatic stellate cells (HSC) of the liver and cause the cells to loss their vitamin A content, which then begins to produce scar tissue. The activated HSC can also constrict blood vessels, reducing the blood infusion to the liver cells and decreasing the oxygen and nutrition supply to the liver cells. The liver damage caused by alcohol is related to the length of time and the quantity of alcohol consumed at a given time.