Some of those books are in libraries and related topics can be found..
I don't buy any books anymore..

I was looking thru one last night that was available on a free reading program (Libby) through my online library account.
The book had quite a list of restricted foods for the elimination time frame..
I don't think I could do that kind of restricted food plan that that one talked about..
But maybe for someone it would work..

I have cut way back on junk, goodies, prepared foods and avoid most overly processed foods.