IFing can be done 3 x a week or for weeks on end to lose weight, however, I'm not sure it is necessary to use it as a WOL every single day - caloric restriction every single day for the rest of one's life - probably not! It is really a tool for weight loss and in the end for weight maintenance. During weight maintenance, fewer days of IFing will be necessary to maintain weight. I don't believe it needs to be an everyday thing forever and a day, but it is a very useful tool to aid in weight loss. Remember Christina? She is an amazing success story. She lost weight low-carbing Atkins-style and for the last 10 lbs, she incorporated IFing, and lost those last few stubborn pounds.