I added something to the post after the copy, repeating here since you were typing at same time:

One point he probably does not repeat enough, and not in The Atlantic, is that his patient population for the most part are obese, very sick if they already have diabetic nephrology, and fast weight reduction is way better than dying on a dialysis machine. People who would like to lose ten pounds..or even thirty, should probably not consider extended fasts. Two days a week or the 16:8 day is more than adequate. Fasting for cancer treatment and other metabolic therapies is another reason fasting is making a comeback, but again, a very specific use for a sick population...not to lose a few pounds before the holidays.

The Obesity Code book has extensive citations for each chapter, I assume the new book does as well.

Steve Phinney disagrees with him on the whole protein issue...says they use different studies to bolster their claims...but they both do have studies.