Is there any way to lift saggy breasts without surgery??

Support bra: Saggy breasts can be supported by a bra that can provide comfort and measured fit. There are no legitimate medical devices other than surgery that can do the same.

Not on earth: The support structure inside breasts influences how they hang. Such traits are usually inherited just like other bodily characteristics. On Earth, we have gravity, so some breasts will sag if they were destined to sag. Without gravity, like on the International Space Station, breasts shouldn't sag, but that's a question best directed to a woman astronaut. However, becoming slimmer is a good idea.