Many of us enjoy a glass of wine with dinner, cocktails with friends or a cold beer on a hot summer’s day. In fact, according to Statistics Canada, almost 8 out of 10 Canadians consume alcohol regularly.
What many people don’t realize is that alcohol is a known carcinogen—a substance that causes cancer. The breast is one of the most sensitive parts of the body to the cancer-causing actions of alcohol. It’s not the type of alcohol that causes cancer, it’s the amount consumed and how frequently. The Canadian Breast Cancer Foundation provides you with information and guidelines about alcohol consumption in relation to breast cancer risk reduction.
Alcohol and breast cancer risk
The World Health Organization (WHO) describes alcohol consumption as a leading risk factor for chronic disease, including cancer—and a greater risk than a high body mass index (BMI), a low intake of fruits and vegetables or being physically inactive.
When it comes to cancer risk there is really no safe level of alcohol consumption, according to the World Cancer Research Fund. It is estimated that 4% of new breast cancer cases a year in Canada may be linked to alcohol consumption. Drinking less alcohol is one way we can take action to reduce our risk of breast cancer.
Recognizing the way we live and the fact that many people do consume alcohol, research on alcohol and cancer risk has led to the development of consumption guidelines.
As a woman, consuming just one standard alcoholic drink every day leads to an increase in your relative risk of developing breast cancer by up to 13%. That risk goes up significantly the more alcohol per day you consume: two drinks a day can increase your risk by up to 27 per cent; three or more drinks per day can increase your risk by 40-50% or higher.
Some smokers, including social smokers, like to smoke when they drink. If that is the case for you, be aware that these two things together further increase your risk of developing breast cancer as well as cancers of the mouth and pharynx, esophagus, liver, larynx and colon.
Women with a higher risk of breast cancer are advised to avoid alcohol or drink it only occasionally. This includes women who have had a breast cancer diagnosis as well as women confirmed to be at higher risk for the disease.
Moderation is key
Knowing what a standard drink is and keeping track of how much alcohol you consume—daily and weekly—will help you reduce your risk of breast cancer and other health conditions. If you wish to assess your drinking or reduce your alcohol consumption, there are support services and programs to help you.
A “standard drink” is:
Wine (12%) 5 oz (142 ml) glass
Beer (5%) 12 oz (341 ml) bottle/glass
Hard liquor (40%) 1.5 oz (43 ml) glass
A standard drink contains 13.6 grams or 17 ml of alcohol. Remember that many drinks, such as “coolers” and some beers, have a higher alcohol content than the standard drink.
Alcohol consumption increases the risk of cancer because all alcohol contains ethanol, a known carcinogen. All alcohol, whether it's wine, beer, hard liquor and cocktails all have the same effect on breast cancer risk. The frequency and amount consumed—not the type—are what’s important.
Health risks outweigh minor benefits for heart health
You have probably heard news reports that drinking a glass of red wine every day can keep your heart healthy. However, studies show that most women under 50, with no signs of cardiovascular conditions, are not likely to benefit from the possible, slight, positive effect that drinking red wine might have on their heart.
Your heart health, breast health and overall health are better served by a balanced diet, regular physical activity and by quitting smoking —or, even better, never starting.
Aronson, K. (2003). Alcohol: A recently identified risk factor for breast cancer. In Canadian Medical Association Journal. Apr 29, 2003; 168 (9).
Butt, P., Beirness, D., Gliksman, L., Paradis, C., & Stockwell, T. (2011). Alcohol and health in Canada: A summary of evidence and guidelines for low risk drinking. Ottawa, ON: Canadian Centre on Substance Abuse.
Canadian Centre for Addiction & Mental Health. Evaluate your drinking. Accessed July 31, 2011.
Health Canada. (2010). Canadian Alcohol and Drug Use Monitoring Survey. Summary of Results. Accessed July 31, 2011.
International Agency for Research on Cancer. (March 2007). Breast and colorectal cancers are associated with alcohol consumption, says IARC. Accessed July 31, 2011.
Roerecke, M., & Rehm, J. (2012). The cardioprotective association of average alcohol consumption and ischaemic heart disease: a systematic review and meta-analysis. In Addiction.
Seitz, H. K et al. (2012). Epidemiology and Pathophysiology of Alcohol and Breast Cancer. In Alcohol and Alcoholism. 2012; 47(3): 204-212.
World Health Organization. Alcohol. Accessed July 31, 2011.