Along with smoking and chronic infections, alcohol consumption is an important cause of several types of cancer, researchers said on Monday.
Excessive drinking raises the risk of cancer of the mouth, larynx, esophagus, liver, colon and breast. It may also be linked with cancer of the pancreas and lung.
“Alcohol is underestimated as a cause of cancer in many parts of the world,” said Dr Paolo Boffetta of the International Agency for Research on Cancer (IARC) in Lyon, France.
“A sizeable proportion of cancer today is due to alcohol intake and this is increasing in many regions, particularly in east Asia and eastern Europe,” he added in an interview.
Boffetta and Mia Hashibe, who reviewed research into the link between alcohol and cancer, found the more alcohol consumed, the higher the risk of developing cancer.
But they advised people to drink moderately, rather than give up alcohol completely, because of its protective benefits against cardiovascular disease.
“Total avoidance of alcohol, although optimum for cancer control, cannot be recommended in terms of broad perspective of public health, in particular in countries with high incidence of cardiovascular disease,” Boffetta said in a report in The Lancet Oncology journal.
Instead, the scientists said men and women should limit how much alcohol they drink to reap the benefits but avoid the dangers.
“The most recent version of the European code against cancer recommends keeping daily consumption to two drinks for men and one for women,” Boffetta noted.
In developed countries in 2000, the World Health Organization (WHO) estimates that alcohol caused 185,000 deaths in men and 142,000 in women, but it prevented 71,000 male deaths and 277,000 female deaths in the same year.
In developing countries, where there are fewer cases of cardiovascular disease, alcohol was linked with 1.52 million deaths in men and 301,000 in women.
The scientists found that alcohol-related diseases were a particular problem in central and Eastern Europe.
“Alcohol is probably the main factor responsible for increased risk of head and neck cancer recorded in various countries, particularly in central and east Europe,” said Boffetta.
Exactly how alcohol increases the odds of developing cancer is not clear but genetic susceptibility is an important component.
“Given the linear dose-response relation between alcohol intake and risk of cancer, control of heavy drinking remains the main target for cancer control,” Boffetta added.