According to the director of the American Cancer Society, quoted in this New York Times article, "the short answer is no."  I would add that the long answer is also no.  But I'm quippy that way.

"Bras cause cancer" is one of those persistent rumors that as far as I can tell exists solely because of the internet.  I wonder how these crazy BS health rumors survived before the internet?  At any rate, as far as I can tell, half the internet believes it.

Only problem is: it's not true.  Bras do not cause cancer.  

Now I agree, there is a weak correlation between "women who wear bras" and "women who get breast cancer."  But even a moment's thought should show you that OF COURSE THERE IS.  Who wears bras?  Older women.  Who gets breast cancer?  Older women.  

This entire brouhaha stems from one scientific study which was conducted poorly, never officially published, and was not subjected to peer review.  As the American Cancer Society's director points out, it had several glaring flaws in its methods.

(But hey, if people were smarter than to believe one crazy unverified unscientific study, no one would believe that vaccines cause autism.  Let's face it: logic isn't the strong suit of a lot of people.  But I digress.)

According to the internet, bras cause cancer because they keep your lymph nodes from draining.  There are two problems with this statement:

1.    Bras still allow your lymph nodes to drain.
2.    Breast cancer doesn't form because your lymph nodes don't get drained.

Let's expand on those two points.  First of all, you can tell that a bra allows your lymph nodes to drain, because when you wear a bra, your boobs do not gradually swell up with undrained lymph.  Trust me, if this was happening, you would notice.  

You know what it feels like when you have PMS and you eat half a bag of Salt and Vinegar potato chips and your feet swell up like water balloons?  That is the result of undrained lymph.  If that was happening to your boobs every day - yeah, you would notice.

Second of all, breast cancer forms because cells take on damage to their DNA which causes them to run amok, replicating themselves into tumor-hood.  This genetic damage does not occur because of compression or lymph or anything else.  DNA doesn't get damaged by bra straps.  It gets damaged through genetic deficiencies passed on from your parents, by toxins which are known to cause cancer, or by radiation.  Not by squishing.

Just to be clear: bras don't keep lymph from draining, and undrained lymph doesn't cause cancer anyway.

So why is this such a popular belief?  I think it is because for so many women, bras are an uncomfortable daily torment.  Anyone who has suffered through a day in an ill-fitting bra could believe them possible of causing anything, from terrorism to - sure - cancer.  

Studies have shown that up to 70% of American women are not wearing a bra that fits correctly.  Do yourself a favor today: take the time to properly measure yourself and buy a bra that fits!

Creative Commons-licensed photo courtesy of Flickr user jenny downing