Does anyone follow the BMI chart for their weight loss?

I want to weigh 160 but the healthy weigh for someone my height is 125-158. I have a shape and I’ve heard other women lose too much weight and their shape and boobs are gone. I think before I gained all my weight I was around a D cup. I’m currently DDD, I’d love to be a D again but I don’t want to start looking like a pencil.