Old wives' tales would have it that sleeping with a bra on will cause your boobs to sag. But in contrast to that, Marilyn Monroe apparently used to sleep with a bra on every night in order to prevent them from sagging. So which is it?
What's the truth in the matter:Will sleeping with a bra on actually have any impact on the shape/size/perkiness of your breasts—either for better or for worse—or could it have any other implications for your health? We asked Dr Seth Rankin, founder of private GP chain London Doctors Clinic, for the definitive answer: Should you, or should you not, wear your bra to bed?
"Breast sagging is an inevitable fact of life for women as they age," says Dr. Rankin, delivering the news we know but would probably rather not hear. The reason being, he explains, is because "the connective tissue holding breasts in place loses its elasticity over time."
Dr. Rankin does note that there are several different factors that can contribute to the increased likelihood of sagging breasts, including "pregnancy and breastfeeding, genetics, smoking, dramatic weight-loss or gain, and perhaps even high-intensity activity." It's this, he says, that makes it "very hard to measure the effect of wearing a bra to bed, with so many other factors having far more significant effects."
But does that mean wearing a bra in bed definitely doesn't have any impact on sagging? Not necessarily, he says.
"Let's think about this from a scientific point of view," says the doctor. "Sagging is caused by the downwards pull of gravity on the mass of your breasts. That's why bigger breasts sag more, as there's more fat within the tissue for gravity to work on."
"When you're lying down flat, the effect of gravity pushes the breast tissue back towards your chest, instead of down towards your toes. So wearing a bra (the purpose of which is ultimately to support breasts from below) is essentially redundant in bed, as breasts naturally compress back down onto the chest."
Dr. Rankin tells that based on this gravity logic, prolonged periods of lying down (regardless of whether you're wearing a bra or not) probably would prevent boobs from sagging long-term. But this would require longer than your average 7/8-hour sleep, and who wants to lie down for 20 hours a day just to make sure your breasts remain perky when you hit the menopause? Not me.
So that seems to be the sagging issue resolved: It's unlikely to have any real effect. But what about any other health implications an all-nighter in your bra might have?
"With regard to the breast tissue itself: If your bra often leaves impressions in your skin from being too tight, then wearing it 24/7 won't give the skin a chance to recover and bounce back from these, leading to long-term indents in the tissue," warns Dr. Rankin.
"Then aside from the breasts themselves, there's a lot going on by way of important anatomy around the chest area: from muscles to vessels, lymph nodes to nerves. If your bra is too tight, you may be restricting your blood supply to the breasts and surrounding areas," the doctor tells us.
"The same goes for the lymphatic system: a tight bra may restrict the flow of lymph to the many important lymph nodes around the breast and armpit, hindering the system's vital function of flushing toxic waste-products from the body," Dr. Rankin explains.
So it's probably best to steer clear from wearing a bra in bed, and that's not to mention the effect it might have on your quality of sleep, especially if it's underwired.
The bottom line from a doctor's point of view, it seems, is that there are plenty of reasons you shouldn't wear your bra to bed; breast sagging just isn't one of them.
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This article originally appeared on Cosmopolitan.co.uk. Minor edits have been made by the Cosmo.ph editors.