For 500 calories, you can eat a regular dinner. Here is a website with items from 200-400 calories: http://www.bbcgoodfood.com/...healthy/200-400-cal/
An example is skinless grilled chicken or fish and all the greens you can eat (350 calories). At some restaurants like Swiss Chalet there are items on the menu of less than 400 calories--which is what I had to eat.
The downside of this "diet" is that I have to count calories, something I've never done my whole life. It has also been an eye opening experience, however, as I did not realize how any calories I eat on a typical day. Some days I eat in excess of 2000 calories. For someone my height of 5'3, the calorie allocation to lose weight is a shocking 1200, and that is a conservative number, with gradual weight loss.
I don't know if I'm losing muscle or fat, although I notice that I've lost much of my jiggle around my middle. It's not all gone, though. There is, however, this from Dr. Mosley regarding whether you lose muscle from IF: http://thefastdiet.co.uk/...-protein-deficiency/
You might want to test your will power-- it is not as difficult as it sounds. As a person who absolutely loves food and has never done a diet in her life, I have been able to do this for a month now. While you are fasting, it is comforting knowing that you will eat that same day, and that the next day you can eat normally again. I also think of the benefit of living longer so I can see my grandchildren graduate from university... not likely, but I am hoping for it. I also think of how my mother is diabetic, or how her father had Alzheimer's. IF helps with both of those conditions.
Thanks for the congratulations. I'm actually not sure how I got here because my weight did not go steadily down. It was up and down, and it was like a surprise when the scale had low readings. The clothes fitting so much better is the best indicator of the weight loss, that it's not just my imagination. I was about to give it up at the end of the second week into this because I did not seem to be seeing any progress in weight loss, but I kept thinking of the longevity benefits.
Thanks for the congratulations! I hope this changes my body set point. We'll see.