Do Bras Cause Breast Cancer?
March 24th, 2010
We, like everyone else, get those email forwards. Sometimes they are funny, sometimes inappropriate, and often full of misinformation. That’s why we love Snopes! Snopes is a website with content that dispells many of the myths perpetuated by these often-irresponsible email forwards. But one we received recently wasn’t about a photoshopped picture or a claim that sushi will put worms in your brain. This was about real life stuff that affects women every day – bras, breasts and breast cancer and a scary comment that they are linked by scientific proof. We needed to learn more – so, we consulted some websites with a little more expertise on the subject. (We list them later in this post).
The email is titled ”Do You Wear a Bra All Day? Even At Home? READ THIS!” The email claims there was a study in the United States proved that women that wear bras 24 hours a day are virtually guaranteed to have breast cancer at some point in their lives. As you can imagine, this claim is not based on any actual clinical study, though it is widely circulated as such. Instead this statistic, if you can call it that, relates to a book called “Dressed to Kill” by authors Singer and Grismaijer. Singer and Grismaijer are not scientists. Instead they are a husband-and-wife team based in Hawaii, who have degrees in Anthropology and Environmental Planning.
The book is based entirely on an unscientific, unproperly documented ‘study’ of 4700 women in 5 major US cities. Their approach, as they admit themselves, did not adhere to any scientific protocols. They simply hoped the findings of their study (outlined below) would lead to the medical industry following up on their findings, and proceeding to do their own study to confirm the claims. The claims are:
We must say, those are some pretty bold findings. Presented at face value, we could see how someone might be frightened by these results. But let us keep in mind other factors when considering the data.
Criticism of the book from the medical and science communities dismiss the book because of “poor methodology, lack of supporting evidence, and Singer and Grismaijer’s failure to consider alternate explanations besides bra use for their findings.”
In fact, one specific critique of the their book by Martha Molete of the Cancer Association of South Africa argues that numerous aspects of the book’s claims are scientifically unsubstantiated or unproven, citing:
- Lack of controlled epidemiological data correlating bra-wearing with the risk for breast cancer
- Lack of proof that the pressure exerted by a bra reduces the flow of lymph
- Lack of proof that lymph contains carcinogens
- Lack of proof that there are carcinogens in the human body that can induce breast cancer
- Existence of published data correlating obesity with post-menopausal breast cancer
Furthermore, none of the authors’ surveys have attempted to account for any of the well-known epidemiological risk factors for breast cancer, such as number of full-term pregnancies, age at first pregnancy, obesity, Western pattern diet, or use of medications such as hormone replacement therapy. Per Molete, “the authors’ statistical treatment of their obtained data appears to be flawed. They do not include the data or a detailed description of the statistical treatment of the data. The two groups, i.e. those wearing bras and those that did not, were not controlled for many other factors influencing the risk of breast cancer.”
There have been no published scientific studies that prove any link whatsoever. In fact, there is a published study that does counter their hypothesis. This study shows that bra usage is not an indicator of increased risk, instead bra size could possibly be an indicator – but bra size isn’t a clear indicator either. In this study there was a link found between postmenopausal women who wore no bras and lower incidences of breast cancer. However the study also noted that this is likely because women who don’t wear bras often have smaller breasts. To prove this theory, the study also studied and noted that among postmenopausal female bra wearers, only those with larger breasts had any increase in incidence. What this indicates is that the link between bras and cancer is non-existent – the actual link is more likely between known risk factors such as obesity and genetics.
Who else says this book/email forward is bunk?
Need we go on? You get the idea. Just one flawed unscientific study printed in a self-published book, does not a fact make! Curious about the authors? Well, according to Wikipedia, they are now working on a new book that explores the dangers (and potential cancer causes) of sleeping horizontally.
Simply put? Their data and research is flawed. There is unflawed and respected scientific research that counters their hypothesis. There is no scientific link, and any website, email or person who tells you differently does not have a basis for their claims.
In our view, perpetuating these fear-inducing myths is not only irresponsible but also dangerous. Do us a favour – next time someone forwards you this email, respond with the link to our post here in your response. Don’t want to link to us? We’re pretty sure any of the above links will do.
Let’s put a stop to perpetuating fear and unease among women. If we can focus on increasing awareness of the real, proven risk factors for breast cancer we will better serve ourselves and our world.
Thanks, from sfys.
