Women don't need to wear a bra, a new French study suggests, saying the under-garment is a "false necessity."
According to the results of a 15 year study bras do nothing to help support a woman's breasts and could even be doing damage.
"Medically, physiologically, anatomically, the breast does not benefit from being deprived of gravity," Jean-Denis Rouillon, a professor at the University of Franche-Comté in Besançon, told France Info.
Conducting the study at the university's hospital, Rouillon measured and examined the breasts of more than 300 women, aged 18 and 35, taking note of how the additional support provided by bras affects the body over time. (The study did not mention breast size.)
Breasts would gain more tone and support themselves if no bra was used, researchers said.
Using a bra meant "supporting tissues will not grow and even they will wither and the breast will gradually degrade".
Some of the women who took part in the experiment told France Info that stopping using a bra had even helped ease back pains.
However, women shouldn't go burning their bras just yet.
Prof Rouillon said: "It would be dangerous to advise all women to stop wearing their soutien-gorge as the women involved were not a representative sample of the population."
He said his initial results "validated the hypothesis that the bra is a false 'need'" but women who had been wearing bras for a long time would not gain a benefit from stopping now.
He said a principle observation was that the nipple would lift 7mm in a year towards the shoulder in those women not wearing a bra. The breast would also become firmer and stretch-marks faded. He suggested that girls who started wearing a bra once their breasts first started to appear would soon become dependent as the supporting muscle structure would degrade.