If you want to, that's fine. But it's your call.
  1. Nipples are not scary. Nobody is going to be mad at you for letting the outline of your nipples be seen through your shirt. Trust me.
  2. If you have small breasts, you don't need the support and you DON'T need to try and make them look bigger. They're beautiful exactly how they are. Trust me.
  3. If your breasts are big, people will tell you that you better support them, otherwise they'll start sagging and by the time you're sixty they'll look gross. Newsflash: they're not going to look incredible when you're sixty no matter what you do. Might as well enjoy the freedom when you're young.
  4. Another news flash: it's your body. Sometimes I wear a bra just because somehow I think it's the law. It's not the law.
  5. If someone views your bralessness as a sexual invitation (which some definitely will), that's actually their problem and not yours. Those same people are prone to interpret even a smile as sexual invitation, so it's unnecessary to make outfit decisions based on them.