Is It Unhealthy to Sleep in an Underwire Bra?

Updated: Oct. 10, 2022

If you like to snooze with your girls strapped firmly into place, here's what you need to know.

Sleeping in a bra is a lot like eating marmite or sardines: You either love it or hate it. Some women see it as a vital sacrifice to maintain a youthful perkiness or just find it more comfortable. For others, sleeping in an underwire bra means struggling to get comfortable in a kind of personal prison. It’s time to figure out once and for all: Is sleeping in an underwire bra dangerous or not?

There has long been a popular myth that sleeping in an underwire bra can lead to breast cancer, but this claim is entirely false, says Neelima Denduluri, MD, oncologist with Virginia Cancer Specialists, the associate chair of The U.S. Oncology Network Breast Committee, and a clinical assistant professor at Georgetown University Medical Center. Dr. Denduluri says the only thing bras and cancer have in common is that they’re linked with boobs. “Underwire bras are not associated with causing cancer at all, sleeping or awake,” she says. “In fact bras of any type are not associated with causing cancer.”

In a study published in Cancer Epidemiology Biomarkers & Prevention, the researchers stress that nothing about wearing a bra—including cup size, number of hours per day wearing a bra, wearing a bra with underwire, or the age women first starting wearing a bra—has any impact on one’s risk of getting breast cancer. So you can definitely rule that out as a reason to avoid sleeping in one.

There’s also no proof that sleeping in an underwire bra hinders bodily circulation. “There’s a popular myth based on the notion that bras with underwire, or that are ill-fitting, or tight-fitting, like a sports bra, decrease circulation of lymphatic fluid and may trap toxins in the breast tissue,” says Caroline Coombs-Skiles, MD, breast surgeon at the Austin Cancer Center. “If this were true, you would see other signs, such as edema (swelling) or fluid accumulation in the breasts, and changes in lymph nodes.”

woman hooking braiStock/zhenikeyevConsidering comfort

There is no medical reason either for or against sleeping in a bra but there is one big reason to consider: comfort. Many women find bras uncomfortable and therefore should go commando in order to sleep better, Dr. Denduluri says. However, some women—particularly those with larger breasts and/or very sensitive nipples—prefer the feeling of support and protection from sleeping in a bra. In that case, it’s a good idea to sleep in whatever type of bra you find comfortable, she says. Use this bra size guide to find the perfect fit.

When it comes to nighttime support, you have a lot of options. Most women will skip the heavy-duty underwire or compression bra they wear during the daytime or sports bra for exercise in favor of a sleep bra or a bralette. Newer designs allow for comfort, support and breathability without binding fabrics or underwire. Here’s what you need to know about going braless.

Just know that wearing a bra to bed will not maintain or improve your breast shape or perkiness. “Gravity is an undeniable force and getting older naturally changes the shape and appearance of your breasts,” Dr. Denduluri explains. “But this is normal and nothing to be ashamed of or worried about.”

Bottom line: Sleep in a bra or go bra-less at night, whichever you’re more comfortable with. Next up: 13 things your breasts won’t tell you.