I agree - 700 calories is not even close to enough to fuel your body properly, and even the days you go over that it isn't enough. If you deprive your body of calories too severely, your body will go into starvation mode and hang on to it's fat to protect itself. Try about 1500. And the calories you do eat should be nutritionally valuable ones - lean proteins, fruits, and veggies.
Man who say it cannot be done should not interrupt man doing it - Chinese Proverb
"Eat food, not too much, mostly plants." Michael Pollan