"Eat food. Not too much. Mostly plants." is the main take away and he doesn't expand into each of these 3 elements until the end. Much of the book is about nutritionism and how whole food has been broken down into separate properties that do or don't affect our health, it seems everything is almost up for debate. Mainly eat whole food that isn't processed, doesn't have generally more than 5 ingredients listed and things you don't know or can't pronounce. Smaller portions, more plants for the nutrients you miss out on through processing. Eat slower and be more in tune with your body telling you its full. Shop more at farmers markets to cut down on chances of buying processed food. Start a home garden. Buy eggs that have been pastured. Buy beef that's been grass finished.