Researchers from the Centre for Addiction and Mental Health say alcohol was linked to thousands of cancer cases in Canada last year, and that even mild to moderate drinking poses risk of developing the disease in the future.
Those findings are part of a modelling study from the World Health Organization's International Agency for Research on Cancer that was published this week in the journal Lancet Oncology.
The global study estimates the effect of alcohol consumption on cancers worldwide, suggesting four per cent of newly diagnosed cases in 2020 may have been associated with drinking alcohol.
In Canada, researchers say alcohol use was linked to 7,000 new cancer cases in 2020, including 24 per cent of breast cancer cases, 20 per cent of colon cancers, 15 per cent of rectal cancers, and 13 per cent of oral and liver cancers.
The study found that most of those alcohol-related cancer cases worldwide were associated with heavier drinking patterns, but researchers estimate that light to moderate drinking, around one or two drinks per day, contributed to more than 100,000 cases in 2020, or one in seven.
Study co-author Kevin Shield, a scientist at the CAMH Institute for Mental Health Policy Research, says alcohol consumption can damage D-N-A.
Those damages can accumulate over time, sometimes causing cancer.