- More cancers could have been prevented in 2012 if Ontario adults had followed the alcohol consumption guidelines from the World Cancer Research Fund (WCRF) and American Institute for Cancer Research (AICR) instead of the Low-Risk Alcohol Drinking Guidelines (LRADG).
- The WCRF/AICR guidelines and the LRADG consider and give different weighting to multiple harms and potential benefits of alcohol consumption.
- Strategies to limit alcohol consumption to the levels specified by drinking guidelines could potentially reduce the cancer burden in Ontario.
Based on a recent study published in the Canadian Journal of Public Health, an estimated 482 alcohol-related cancer cases could have been prevented in Ontario in 2012 if Ontario adults had followed cancer-specific alcohol consumption guidelines from the World Canada Research Fund (WCRF) and the American Institute for Cancer Research (AICR). Only an estimated 321 cases could have been prevented if adults had followed the Low-Risk Alcohol Drinking Guidelines (LRADG).
When examined by cancer type, the greatest reduction as a result of following both sets of guidelines would have been observed in the number of alcohol-related oral cavity and pharynx cancer cases. This type of cancer is less commonly diagnosed in Ontario, but alcohol consumption is strongly associated with it. A substantial number of cases of colorectal and female breast cancer—two of the most commonly diagnosed cancers in Ontario—would also have been prevented if alcohol consumption was reduced to levels within both sets of guidelines.
The International Agency for Research on Cancer has classified alcohol consumption as carcinogenic to humans, citing sufficient evidence that it causes cancers of the oral cavity, pharynx, larynx, esophagus, colorectum, liver and female breast. Alcohol is also associated with other chronic diseases and acute conditions, and there is some evidence of detrimental and protective effects of alcohol consumption on cardiovascular disease. While the alcohol amounts specified in the WCRF/AICR guidelines are lower than those in the LRADG, the WCRF/AICR acknowledge that there is no safe limit of alcohol consumption to prevent increased cancer risk. Both sets of guidelines consider multiple harms and potential benefits, but the weighting of each is different.
In Canada, two sets of guidelines are commonly promoted to help individuals reduce their alcohol-related harm. The LRADG state that to reduce long-term health risks, men should drink no more than 15 drinks per week, with no more than 3 drinks per day on most days, while women should drink no more than 10 drinks per week, with no more than 2 drinks per day on most days. The WCRF/AICR cancer-specific guidelines are more conservative than the LRADG and state that if alcoholic beverages are consumed, consumption should be limited to no more than 2 drinks per day for men and 1 drink per day for women, which translates to 14 drinks per week for men and 7 for women. The WCRF/AICR guidelines have been adopted by several cancer-related organizations in Canada, including Cancer Care Ontario and the Canadian Cancer Society., In 2012, 8.8% of Ontario adults reported drinking more alcohol than recommended by the WCRF/AICR guidelines.
In 2012, 1,295 (95% confidence interval, 1,093–1,499) new cancer cases diagnosed in Ontario are estimated to be from alcohol consumption. However, it is estimated that 974 (822–1,124) alcohol-related cancer cases would have been diagnosed if no Ontario adults had exceeded the LRADG. If alcohol consumption had been even more conservative and had not exceeded the cancer-specific WCRF/AICR guidelines, only an estimated 813 (690–935) alcohol-related cancer cases would have been diagnosed.
While completely eliminating alcohol consumption in Ontario is likely not feasible, adherence to the recommendations outlined by the WCRF/AICR guidelines as opposed to the LRADG could substantially reduce alcohol-related cancer cases in Ontario adults. Strategies that focus on limiting alcohol consumption to the levels recommended by drinking guidelines, and preferably to the WCRF/AICR guidelines, could potentially reduce the cancer burden in Ontario.