A couple of months ago I gained 10 pounds in just 3 weeks for no real reason. I wasn't overeating or anything at all. I freaked out about it and for 3 months I went on every diet pill availible. It didn't help and I stayed the same. Finally I gave up and stopped and then in 1 week, I gained another 5 pounds. I usually don't have this problem. I might gain about 3 pounds in the winter but then just lose it effortlessly in the summer. I've never had a problem like this. I've been the same size and weight since high school. Does anyone know of any medical reason why this might be happening? I'm hesitant to call my Dr. Help, i'm a 30 yr old female.