Is Sleeping In A Bra Good Or Bad For You?

Unsurprisingly, there is a lot of contention around the notion of sleeping in a bra. While some women instantly recoil at the idea (a very uncomfortable suggestion, according to a few ladies in our office), others claim the extra support will prevent sagging and keep things looking, well, up. There is also a lot of confusion around the topic, and the so-called benefits and possible health risks. Outside of possible annoyance, some research has suggested that wearing a bra at night could even potentially cause breast cancer. Which of these claims is true, or are neither? Does wearing a bra to sleep do more harm than good, or did Marilyn Monroe, an alleged nighttime-bra-wearer, know better than us all? 
In this week's installment of Beauty Myths, we enlisted Dr. Amber Guth, associate professor of surgery and director of the Breast Cancer Surgery Multidisciplinary Fellowship at NYU Langone Medical Center, to break down these claims from a health perspective. We also spoke with Linda Becker, a.k.a. The Bra Lady, a professional bra fitter who owns boutiques in New York, as well as Erica Cheung, one of our interns, who's been wearing a bra since she was three, and until recently slept in an underwire version every night. 
"There is certainly no evidence that sleeping in bras is either helpful or harmful," Guth says. "Sagging or changes in the breast are due to a number of factors: Pregnancy and breastfeeding being the most common causes, along with time and gravity."
Yet, gravity is the reason that Becker, who's been bra-fitting for over 25 years, contends that sleeping in a bra can only be beneficial. "Here's the logic," she tells us. "Either your breasts are being supported for eight hours, or they're not being supported for eight hours. What do you think is better? It's just common sense. If your breasts are being held up, they're going to stay up a lot longer. When you take your bra off at the end of the day, they're a lot higher than when you put it on in the morning." She was explicit about which women should be wearing a bra at night. "It really depends on the size of your breast," Becker explains. "If you're an A-cup or B-cup, no. If your breasts are bigger than a D, Double-D and up, you should. Some people's breasts hurt them when they sleep, so they need to wear a bra. Some people need it for support."
Which leads to another unclear area: how much support women actually need. "I started wearing training bras regularly when I was about 10 and I slept in them -- they were basically like sports bras so they were super comfy," Cheung says. "Only when I started wearing bras with more support and underwire did I realize that sleeping in them wasn't very comfortable, but I got used to it. Occasionally, the underwire in my bras hurt and I would wake up with my bra all off-kilter and half way wound behind me. I mainly did it because my mom told me that it was good for me and that I basically had to."
It's this discomfort that has alarmed many into thinking there are potential health risks attributed to wearing a bra at night. Becker, who was adamant about the importance of fit, says that women "should never sleep in a bra with a wire, it should be a soft-cup bra. Sleeping in a bra with a wire can give you cysts or irritate your breasts."
Similarly, Guth warns of an ill fit. "Certainly no bra or breast support should be so tight that it constricts or blocks any form of circulation. However, if the routine use of bras contributed to lymphatic blockage, you should be seeing other signs such as edema or fluid accumulation in the breasts, and earlier, non-cancerous changes in the shape/size of the axillary lymph node. These lymph nodes in the underarm area drain the breast, and are the body’s first defense against infection, foreign material, cancer cells. They act like a filter, cleaning out the lymph fluid." In layman's terms, Guth went on to clarify that "scientists are certainly looking at the chemistry of the breast, trying to see if there are different pathways at the molecular level that predict or are permissive for breast cancer development, but strongly doubt that external devises such as brassieres would have any effect on these pathways. Sleeping in a bra or support bra really is just a matter of the woman’s personal comfort, and that is what I advise my own patients."
Conclusion: There is no direct connection between sleeping in a bra and breast cancer, however wearing a bra at night could offer more support or comfort, if needed.
For Beauty Myths, we've enlisted the help of pros to help debunk and demystify some of the most popular advice out there. Do you have a myth you'd like us to investigate? Let us know in the comment section, and check out previous questions in the gallery below.