I don’t know much about this particular individuals claims. As McKenzie has already said there are far too many people trying to make a buck from the latest diet book or supplement that its nearly impossible to keep up with them.
There are a few easily recognizable clues that a particular diet or supplement purveyor is a fraud
1) They claim that they know something the rest of the medical community does not
2) They claim that you can eat whatever you want and still lose weight. There is no such thing a free lunch.
3) They make you purchase their book to learn the secret. Legitimate medical information doesn’t travel that way. It is open source and available to everyone free of charge
Finally, anyone who claims that there is “no such thing as calories” is by definition a fraud since they are denying well established basic principals of physics and biology going back to the time of Newton. But if you want to sell a book you have to claim something radical and appear to have some secret no one else knows about.