The premise for this book is that food can either make you healthier or less healthy-- there is no neutral food. Foods that make you less healthy do so in at least one of the four following ways: 1) they have a psychological addiction to them, 2) they mess with your hormones, 3) they mess with your gut, and/or 4) they mess with your immune system.
This book explains the concepts in a simple yet logical way that has the science to back it up. The authors do a lot of "talk to the reader" kind of writing which usually bothers me but for some reason I wasn't annoyed with them. It's a book that I would recommend to family and friends because as the authors put it at t the beginning, I "deeply care for their health."
In the appendix they have simple ideas for how to cook food every day in a sustainable way (not environmentally sustainable but sustainable in the sense that it's doable) and I was super inspired to cook more, even though I already have a husband who loves to cook for me and he does it well. Great resource and great read.