So that French ‘study’ by Roullion was a wildly unscientific mess, just so you know. We still actually don’t know anything about whether there’s a medical reason for bras or not. I suspect the answer may differ depending upon how large one’s breasts actually are, and maybe also age.

Personally, I almost never wear a bra anymore, but then my breasts, even with perimenopausal weight gain, are not that large (36C/D), and my Sensory Processing Disorder is a big strike against bras.

(See https://skepticalinquirer.org/exclusive/dont_burn_your_bra_for_science_just_yet/)