It’s no secret that genetic, hormonal and environmental factors all seem to play a role in breast cancer. When it comes to alcohol and breast cancer risk specifically, a May 2016 study provides even more insight suggesting that lifestyle factors — including how much alcohol a woman drinks — really matters.
Danish researchers published a study in the British Journal of Medicine providing even more detail of the alcohol and breast cancer risk connection. Analyzing women’s change in alcohol consumption over a five-year period, Danish researchers found that women who increased the amount of alcohol they drank over a five-year period faced a higher risk of breast cancer.
For instance, women who drank two more alcohol drinks a day over five years saw a 30 percent increased risk of breast cancer compared to women with stable alcohol intake. That same study found a 20 percent lower risk of heart disease in woman who drank more. However, the study authors noted there are other ways to lower heart disease risk without increasing your breast cancer risk from drinking alcohol.
Alcohol and Breast Cancer Risk Findings
Research consistently shows that drinking alcoholic beverages increases a woman’s risk of hormone-receptor-positive breast cancer. Alcohol not only damages DNA in cells, but it also triggers higher levels of estrogen and other hormones linked to hormone-receptor-positive breast cancer. Compared to women who don’t drink at all, women who have three alcoholic drinks per week have a 15 percent higher risk of breast cancer. The estimated alcohol and breast cancer risk increases another 10 percent for each additional drink women regularly have each day, according to breastcancer.org.
Here are more important alcohol and breast cancer risk findings:
A large meta-analysis looking at the relationship between alcohol and breast cancer risk in women also found that women who drank about three alcoholic drinks a week experienced a moderate increase in breast cancer risk.
A 2009 study found that drinking just three to four alcoholic beverages a week increases a women’s risk of breast cancer recurrence in women who’d been diagnosed with early-stage breast cancer.
In March 2016, University of Houston researchers found that alcohol not only fuels estrogen that drives the growth of breast cancer cells, but it also diminishes the effects of popular cancer drug Tamoxifen, a widely-used estrogen-blocking drug used to treat many breast cancers.
The U.S. Centers for Disease Control and Prevention advises women to drink no more than one drink a day. If you drink less than this, don’t increase the amount of alcohol you drink.
Defining a “Drink”
When considering all of this research investigating alcohol and breast cancer risk, it’s important to understand what a “drink” actually means. For instance, drinking one dirty martini is very different than drinking a glass of beer or wine. Each may seem like a single drink, but a dirty martini typically contains about 6 ounces of vodka. That means your single martini, for instance, would actually be considered four drinks.
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