Alcohol is processed by the liver, where enzymes break it down into toxic substances like acetaldehyde. Excessive drinking causes fat buildup (fatty liver), inflammation (alcoholic hepatitis), and long-term scarring (cirrhosis). Over time, liver function declines, affecting detoxification, digestion, and blood sugar regulation. Heavy alcohol use also increases the risk of liver cancer. Damage can be partially reversible in early stages but becomes permanent with chronic abuse.