If a food is fat free, you can eat unlimited
This is true that a diet high in fat is not good for health but a food which has no fats may have other poor nutrients like sugar and salt. Also fat keeps you full, to begin with, opt for good fats as in avocados, nuts and fish etc.; otherwise you may feel constant hunger and end up with consuming more calories. Also remember, a calorie is a calorie whether comes from fat, carbohydrate or protein.