Fully agree on diet, but you should look at some of the data presented in the book.  There is evidence - particularly the book talks about gut sterile mice and some of the studies showcasing weight gain scenarios vs non-sterile biome mice on an exact diet.  While it&#x27;s no silver bullet, dismissing the value of a healthy gut is not productive either.  No evidence doesn&#x27;t mean there isn&#x27;t something worth pursuing.  It&#x27;s a relatively greenfield area of study at this point in time which is why it&#x27;s interesting to watch it unfold.