There are benefits to not wearing your bra. And a big advocate of that is sport science researcher Jean-Denis Rouillon, who has, after a 15-year study, found the effect of bras on 330 women aged 18 to 35. Basically, he says, don't wear them.

From IFL:

The findings suggested that wearing a bra from an early age did nothing to help support the chest, reduce back pain or prevent breast sagging. “Medically, physiologically, anatomically – breasts gain no benefit from being denied gravity. On the contrary, they get saggier with a bra,” Professor Rouillon told France Info in an interview.

"For younger women, not wearing a bra will lead to increased collagen production and elasticity, which improves lift in a developing breast," said Dr. Stafford Broumand, who was not connected with the study, for Refinery29. Of course, many women wear bras for other reasons than to just reduce the sag of their breasts.

Here are some women adhering to that research:

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