Bras can protect breast tissue and keep the breasts supported. Some girls may also like that bras smooth out their silhouettes and make them feel more comfortable. A bra can make a girl feel less exposed when she's wearing a light shirt, such as a T-shirt.

What happens if you don't wear a bra?

"If you don't wear a bra, your breasts will sag," says Dr. Ross. "If there's a lack of proper, long-term support, breast tissue will stretch and become saggy, regardless of breast size." ... Aside from the aesthetics, a lack of proper support (i.e. not wearing a bra) can also potentially lead to pain.

What is the purpose of wearing a bra?

The bra's main function is to support the weight and structure of the breast. However, women often have a lot of tension and stiffness localised where the bra strap is placed. Tight bras can also severely affect the ribcage, as well as cause back and neck pain.