I don't want saggy tits plz help

I'm 16 and about 200 pounds ☹️!! I am going to start eating healthy and I do excersize so I will keep that up. The thing is if I lose weight slowly will my tits stay good. I only want to lose slowly to like 140-160 is my goal weight in 12 months. Plz tell me how to avoid getting saggy breasts or if I will be fine. Or tell me your weight loss journey and what happened to your breasts.