Newly proposed guidelines for alcohol consumption say Canadians should stick to a maximum of two drinks per week in order to reduce their risk of negative health consequences.
A report published by the Canadian Centre on Substance Use and Addiction (CCSA) Monday follows two years of research and a review of more than 5,000 peer-reviewed studies, and says alcohol in even small quantities can be harmful.
The current Health Canada guidelines, which were also created by the CCSA and last updated in 2011, say men should limit their alcohol consumption to no more than three drinks per day and 15 drinks per week, while women should stick with a maximum of two drinks per day and 10 drinks per week.
Under these guidelines, "one drink" is defined as 12 oz. of beer with 5 per cent alcohol, 5 oz. of wine with 12 per cent alcohol, or 1.5 oz. of hard liquor with 40 per cent alcohol.
But now, the CCSA says even three to six drinks a week can increase the risk of developing certain cancers, such as breast cancer or colon cancer, while more than seven drinks per week can increase the risk of developing heart disease and stroke.
"The risk of negative outcomes begins to increase with any consumption, and with more than two standard drinks, most individuals will have an increased risk of injuries or other problems," the authors write in the report.
Cancer, the CCSA notes, is the leading cause of death in Canada and alcohol can cause at least seven different types of cancer. Heart disease is the second leading cause of death, and the CCSA says research over the last decade has shown that alcohol can cause problems for the heart.
"For many years, the commonly held belief that drinking in moderation offered protection against heart disease has been widely publicized. Research in the last decade is more nuanced with the most recent and highest quality systematic reviews showing that drinking a little alcohol neither decreases nor increases the risk of heart disease," the report states.
"At higher levels of use, alcohol is a risk factor for most types of cardiovascular disease, including coronary artery disease and heart attacks, heart failure, high blood pressure, atrial fibrillation and stroke," it continues.
These health risks remain the same regardless of what type of alcohol is being consumed or how much alcohol tolerance the individual has, the CCSA says.
The CCSA also warns that the lifetime health risks from consuming more than two alcoholic drinks per week "increases more steeply for women than for men." Because of differences in enzymes, genes, body weight, organ function and metabolism, the CCSA says alcohol has a greater impact on women and carries a higher risk of liver damage and diseases such as breast cancer.
On the other hand, men are more likely than women to drink in excess. As a result, men are also more likely to be involved in impaired driving collisions or become hospitalized for alcohol-related medical emergencies, the CCSA says.
"Overall, disproportionately more injuries, violence and deaths result from men’s drinking," the authors write.
The CCSA also notes that alcohol consumption, especially for men, has also been frequently associated with violent behaviour, including intimate partner or sexual violence.
"No exact dose-response relationship can be established but consuming alcohol increases the risk of perpetrating alcohol-related violence. Thus, it is reasonable to infer that individuals can reduce their risk of perpetrating aggressive or violent acts by limiting their alcohol use," the report states.
The CCSA has also begun a six-week online public consultation on the new drinking guidelines. Until Sept. 23, members of the public are invited to share their thoughts on in an online survey.
"We want people in Canada to have the latest evidence-based advice on alcohol to support them in making informed decisions about its use," CCSA CEO Alexander Caudarella said in a news release. "We’re excited to enter these final stages. The feedback we receive will help us ensure the clarity and validity of the final updated Low-Risk Alcohol Drinking Guidelines we’ll be releasing this fall."