My aunt Denise told me underwiring was “basically corsetry for your chest and will leave you hanging by forty” over a barbecue dinner in 2019. I was twenty six, had had three glasses of warm rosé, and believed everything she said. I went home later that week and chucked every push up bra I owned into the back of the wardrobe ashamed. Four of them, two black, one nude, one hideous cherry red one I’d bought on a hen do and actually kind of liked. Tried them on recently and all of them still fit, thankfully. Every outing for the best part of two years was spent wearing soft bras instead because a woman who believed kombucha cured everything had ensured I fully believed my chest would end up somewhere around my belly button by the time I hit forty.
I bring you this tiny snippet of lifestyle newsletter autobio because I feel like most of us learned that particular scare from the same place. Not a scientific study or medical professional. An aunt. A hairdresser. Some randomperson870 who commented under your Facebook photo. Your mum who read an article about boobs and has been spreading misinformation ever since. They’ve all told you push up bras and underwire cause sagging because it sounds scientifically plausible; muscles become lazy if you don’t use them, tits have muscles, presto, just like that theory about bulls not having testicles. It’s easy to believe if you don’t know enough about how human breasts actually work to question it. And once you hear it once, you’ll start seeing it everywhere; in Facebook comments and group chats, quoted verbatim by people who have absolutely zero clue what’s actually inside your boobs but have heard the same theory so many times they’re repeating it as fact, myself included until very recently.
Where the actual myth originates from
The theory that “push up bras cause sagging” sounds a little like this; breasts are partially made of muscle. Supporting them with a bra all day weakens that muscle over time like wearing a plaster cast would weaken your leg, thereby reducing their ability to “lift” themselves naturally over time. The whole thing hangs together. Almost sounds biological. It’s not, though, not even a little bit. Once you dig into actual research instead of just Googling until you find a headline that backs up what you want to believe, you realise that breasts don’t contain any muscle at all. Not that muscle your gym teacher talked you through in Health GCSE. None of it. Breast tissue is glandular tissue and fat attached by connective tissue and ligaments, mostly one pair called Cooper’s Ligaments which act very similarly to scaffolding. The pectoral muscle under it isn’t attached to breast tissue at all, and doesn’t get bypassed by wearing a bra in any way.
As soon as I realised that my tits actually didn’t contain anything remotely muscle like, the whole lazy muscle theory crumbled for me. If your breast tissue doesn’t contain anything that could possibly become “lazy” from being supported by a bra all day, then supporting them can’t possibly cause them to sag. Everything that can cause breasts to “sag” or change shape as you age – and plenty of things can do this aside from bras, which I’ll get into – happens at the ligament level, or is genetic. Things like ageing and loss of skin elasticity (hello knees, my old friend), gravity, certain bits of pregnancy and breastfeeding, dramatic changes in weight cause ligaments to stretch and hold that shape, while things like smoking can speed up tissue degradation because collagen and elastin matter more than most people realise. But the main thing that affects sag is movement; when your breasts move around without anything supporting them (i.e. when you’re not wearing a bra), it puts tiny amounts of stress on those Cooper’s ligaments each time, stretching them out little by little. Over years, decades, thousands of times per ligament.
If anything, when you actually look into the science on this, wearing bras -underwire or not- is likely preventing sag more than causing it; support bras worn during exercise have been shown to reduce movement and strain on those ligaments during high impact activities. Proper support, especially during exercise, reduces the movement of breasts independent from your ribcage, which in turn reduces unnecessary stretching of those ligaments over time. Wear a bra while you run, especially a supportive, well fitted underwire or sports style bra, and you’ll reduce that movement and subsequent strain dramatically.
What Push Up Bras Actually Do and Don’t Do
Bear with me though, because I think the actual problem with push up bras and sagging rumours comes from these two sentences not being treated as separate ideas nearly enough. Just because support bras don’t cause sagging doesn’t mean a push up bras specifically can’t. They do not, though; not in the way people fear. But they do something else. A push up bra lifts your breasts by utilising padding – most commonly at the sides and bottom of the cups – as well as the actual wire and usually a slightly tighter, higher set band to push and hold breast tissue away from your chest and towards your neck. It’s rearranging the ones you got for aesthetics alone; as soon as you take the bra off your chest will still naturally point wherever it would’ve pointed whether you wore that push up bra today or not.
The issues I personally saw with push up bras when I stopped wearing them for two years came from wearing the wrong size, which is something I only learned because I actually asked to be properly fitted for once instead of going back to my old brand and having that pop up suggested like it knew me. I wore 34B push ups because that’s what I was told when I first started buying myself real bras a few years ago. By the time I actually got measured for fun recently, I was a 32C with a band that was too small and cups that were too small and big around my back. Push up bras have wires for a reason, and mine sat directly on top of my breast tissue and around my armpits rather than around them both, digging into me at the bottom where the lace was until I wouldn’t even wear it for longer than half a day at a time to avoid the bruise. Again, that’s not sagging. That’s buying the wrong size and being irritated every time you put your bra on until your thirties roll around and you assume that nipple deep scratching is normal. It happens WAY more than you think; ask any of my friends and they’ll happily tell you stories about how badly they were fitted and why they vowed never to go near a brassiere section again.
Another friend of mine, Saoirse, wore the wrong band size on purpose for thirteen years because a sales assistant guessed at New Look once and she never bothered researching or asking for a professional fit again. When she finally got helped at Angelahi proper earlier this year she burst out of the changing rooms laughing so hard at how much better she felt when her sales assistant asked her if she was sure, because it felt THAT different after years of rocking a bra two entire band sizes too big. “THIRTEEN YEARS” is what she text me afterwards. Saoirse thinks her boobs feel ruined from wearing the wrong bra size for over a decade. Don’t worry about the negative lift of padding, ladies. Find your correct size. Trust me.
The Verdict, Finally
So, do I think push up bras cause sagging? After investigating where the myth comes from, and understanding exactly what these bras do and how our breasts are actually built? Hell no. They do not cause sagging. Bras don’t know they’re push up bras when they strap you in the morning. All Cooper’s ligaments care about is if you’re wearing a bra that fits well and moves with you when you move, or if you left your support at home on the day you decided to run your fastest 5K yet and now those babies are flinging from side to side all over the place. But even that, when it comes to how your breasts look in ten or twenty years, isn’t the push up bras’ fault. It’s a high impact activity with them too loose, or not at all. Same difference.
So…is there anything about bras you should actually be worried about, sis? Hell yeah; wearing the wrong size. My underwire pushed in so far it left actual red marks I could feel when I took my bra off for the last two years because I refused to go up a cup size and deal with my ribcage itching under the band. That’s not caused by wearing a push up, but it’ll totally damage tissue and your trust in humanity over time if you let it. Get fitted. Try a million brands until you find ones that know how to measure you properly. Heck, take a friend with you so you can commiserate about how your bras feel like wrestling bears once you’re done. Push up bras aren’t clandestine agents of destruction wearing padded vests. They just lift your boobs up and strap you in tighter than you might realise they can.
I think I’m going to apologize to my push up bras, to be honest. All of them. They didn’t do anything to my chest. Leave it alone, they’ll be fine. As for Denise; I love you forever but you were wrong, barbecue queen. SO wrong. And I’m wearing the cherry red hen do number again. Bought another one specifically because it still fits, incorrectly sized, and feel zero ill about it rolling my twenties coming.
