"The FastDiet" is a book by Dr. Michael Mosley and Mimi Spencer, published by Atria Books.
This little book is too expensive, and therefore I don't recommend buying it until the price drops by half. The majority of the content is nice-to-know, with just enough scientific rationale, so it's not overwhelming. The text also contains many sample recipes and food charts. I did buy the book, but I found that I didn't need it to derive the value from its thesis.
The good news is this program does NOT deprive you of food, but rather it reduces caloric intake intermittently. There is compelling scientific data that this kind of regimen is familiar to our bodies- perhaps it's ancient, in our DNA. There is evidence that the program is beneficial to our overall health.
The idea is to restrict your total caloric intake every third day to 500 for women and 600 for men. On the two days between, you just eat what you normally eat . As you see, just two days out of the week are calorie-restricted.
A variation on this diet is to restrict calories every other day, and that proves to reduce weight faster. Once the desired weight is attained, the regimen would be changed to the every third day version first mentioned.
I've been on it just two weeks, and I am down a couple of pounds and I seem to have more energy and a clearer head. I will follow-up on this.
Go to Amazon.com, search the book and go to "Look Inside" and read the liner notes, chapter titles, and some paragraphs from the text.