All of those pop self help books need to be taken with a grain of salt and not assumed to add up. Every diet books falls in that category, books like that "wheat belly", Aitkens, whatever, it's all the same idea of cherry picking stuff to support a thesis.

Born to run about barefoot running and the tara-humara Indians...

Studies in context as a practitioner in the field may mean something, in a self help book and the like, they just are there to lend some legitimacy.

Belive it or not, Michael Crichton's very well referenced "State of Fear" has even been called into question.