Is there a non surgical way to firm breasts?

Hi. This is something I've struggled with ever since my breasts developed, I'm only 23 now but I've become insanely insecure about this more each day. I would love to hear from fellow women who are struggling or have struggled with the same issue. I know there's surgery but I'm curious about the "natural" ways such as doing certain exercises, massage techniques, vitamins/supplements or eating specific foods, Has anyone actually tried anything and found it worked at all? I would love to know as I'm willing to try anything to gain some confidence. Or have you tried loads to no prevail? Then I will try and move on from this self hatred. Thank you x