If you have been starving yourself for a long time and then suddenly eat 2000 calories will you gain weight?

You will gain weight much more rapidly if you start eating 2000 calories a day of you have been starving yourself beforehand.

If you want to start eating a healthy amount of calories again you need to work up to it slowly, you should start eating a little more each day until you feel your eating enough.

hope it helps (im no expert)