I am underweight&when I 1st met my new PCP he walked in with my chart(with my height/weight/BMI) and said, "so another anorexic case, huh? What kinda eating disorder do u have?" I've been thin all my life, weighed more@times&weighed less@times&never thought I had a problem. But then I realized that I purposely don't eat sometimes or restrict myself2empty calories like soda, coffee&juice and candy or junk food. So I talked2him bout it&realized I'm doing these things cuz I feel outta control with my BPD. Talk to your doc&see why he thinks ur anorexic&see what u can do2change it