Cancer
"Habitual drinking increases the risk of cancer," says Jurgen Rehm, PhD, chairman of the University of Toronto's department of addiction policy and a senior scientist at the Centre for Addiction and Mental Health, also in Toronto. Scientists believe the increased risk comes when the body converts alcohol into acetaldehyde, a potent carcinogen. Cancer sites linked to alcohol use include the mouth, pharynx (throat), larynx (voice box), esophagus, liver, breast, and colorectal region. Cancer risk rises even higher in heavy drinkers who also use tobacco.