The Complete Guide to Fasting (Jason Fung) is ridiculous

I understand how periods of intermittent fasting can be helpful for weight loss, by lowering insulin for the insulin resistant and by limiting the time period in which calories are consumed. Many in this sub seem to scoff at the science that says hormones have an effect on weight loss. However, trying to get through this book by Dr. Jason Fung… he makes such sweeping generalizations that CICO “doesn’t work” without explaining why or what he means.

He means it “doesn’t work” because it’s hard; because people are not consistent with their tracking and give up, and therefore it “doesn’t work.” Not properly tracking is not the same as it not working.

He also talks about a contestant on the U.S. television program The Biggest Loser who lost 239 pounds but “was now burning 800 calories less per day” than previously, so he regained all the weight. Well, OF COURSE someone who lost the weight of an entire obese person (or two skinny people) would have a lower TDEE than before. Dr. Fung doesn’t address that at all; he just says the contestant wrecked his metabolism with calorie restriction, completely ignoring the fact that someone 200 pounds needs less calories than someone 439 pounds. It’s ridiculous.