I am currently on a restrictive diet of about 700 calories per day. I am a 24 year old female, 5 foot 1 and at a healthy weight, I do not want to gain or loose but I think calorie restriction has gone out of hand and would like to increase to about 1200 which according to my fitness pal is my BMR. I do not exercise but I do walk about 15 min most days just to get to work and 15min to get back. I have lost a lot of muscle mass and feel hungry and this is why i would like to increase, but I am so scared of gaining weight. If I increase what could happen to my body?