From Google.
Women wear bras primarily for support and comfort, particularly for larger breasts, as a bra can help alleviate back pain and provide structure to the chest, especially during physical activity; additionally, some women wear bras for aesthetic reasons, to enhance their appearance, or to conform to social norms, though the decision to wear a bra is ultimately a personal choice.
I personally wear a bra because I have fairly large breasts. I feel way more comfortable with a bra on when I'm out, and would never go out without one. Although having said that, I can't wait to get it off when I get home, and never wear one in the house. Considering I have fairly large breasts, they are not saggy. (I am in my late 50s.) I have always been quite fit and active though, so I think that's why they're fairly OK.
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