Light consumption of alcohol increases the likelihood of cancer of the mouth, pharynx, esophagus, and breast, and is responsible for 34,000 deaths a year worldwide, according to a new study in Annals of Oncology (August 21, 2012).
In the study, researchers from the University of Milan in Italy used observational studies on alcohol consumption from PubMed and Embase articles published before November 2010. They estimated that in one year alone light drinking caused 24,000 deaths from esophageal cancer, 5,000 from oral and pharyngeal cancers, and 5,000 from breast cancer.
Light drinking was defined as one drink a day. Low alcohol intake increases the risk of esophageal cancer by almost 30%, oral cavity and pharynx cancers by 17%, and breast cancer in women by 5%, according to the study.
Just why light intake increases the risk of some cancers and not others is unclear. The researchers suggest that with cancer of the oral cavity, pharynx, and esophagus it may be because the alcohol comes into direct contact with the affected tissue.
They suggest the rise in risk for breast cancer may be associated with increased levels of estrogen or higher levels of insulin-like growth factors that are produced by the liver after drinking alcohol.
