If you are on bipolar meds, that is the likely explanation.
It seems to me that in america a lot of people are diagnosed with bipolar when really its more that they are borderline and not bipolar at all. Anyway that's neither here nor there with regards to weight.
Don't try to starve yourself. While you are motivated try reading some books by Dr Amanda Sainsbury-Salis who has written the Don't Go Hungry Diet book and Don't go hungry for Life book.
Lots of useful concepts and information and a better strategy than most that are on offer around.
you are young, so its important that you don't get on the diet treadmill and just watch your weight go up and up through your life. The books by this women could probably help you avoid that better than most i think.
I have battled depression most of my life. I understand how when that's going on, its hard to manage ones eating.
