Alcoholism can kill in many different ways, and in general, people who drink regularly have a higher rate of deaths from injury, violence, and some cancers. The earlier a person begins drinking heavily, the greater their chance of developing serious illnesses later on. Any protection that occurs with moderate alcohol intake appears to be confined to adults over 60 who have risks for heart disease. Adults who drink moderately (about one drink a day) have a lower mortality rate than their non-drinking peers, their risk for untimely death increases with heavier drinking.
Alcohol may not cause cancer, but it probably does increase the carcinogenic effects of other substances, such as cigarette smoke. Daily drinking increases the risk for lung, gastric, pancreatic, colorectal, urinary tract, liver, brain cancers, and leukemia. About 75% of cancers of the esophagus and 50% of cancers of the mouth, and throat are attributed to alcoholism. (Wine appears to pose less danger for these cancers than beer or hard liquor.)
Smoking combined with drinking enhances risks for most of these cancers dramatically. When women consume as little as one drink a day, they may increase their chances of breast cancer by as much as 30%.
In the liver, alcohol converts to an even more toxic substance, which can cause substantial damage. Not eating when drinking and consuming a variety of alcoholic beverages are also factors that increase the risk for liver damage. People with alcoholism are also at higher risk for hepatitis B and C, potentially chronic liver diseases than can lead to cirrhosis and liver cancer. People with alcoholism should be immunized against hepatitis B; they may need a higher-than-normal dose of the vaccine for it to be effective.
Alcohol has widespread effects on the brain. The use of alcohol, however, eventually produces depression and confusion.