pollan starts out the book giving his history with researching food and health issues. pollan is a journalist, and figured that with enough research he could get to the bottom of the whole debate of which foods are and aren't healthy (low fat? low carb? meat or no meat? etc etc.) unfortunately, the more research he did, the more he realized that the field of nutrition is just too young and doesn't really have a lot of firm answers.
the only thing that became clear from his research is that the western diet (ie lots of processed foods, high in sugars, refined grains and vegetable oils) is the only diet proven to make people sick (the vast majority of people in the whole world with obesity, type 2 diabetes, heart disease and many cancers eat the western diet).
on the other hand, people who eat traditional diets have very low incidences of these diseases, with a very broad spectrum of what their traditional diets consist of. he gives examples of traditional diets that are very high in fat (the inuit of greenland subsist mostly on seal blubber), very high in carbohydrates (native central americans eat lots of corn and beans), and very high in protein (the masai in africa live mostly on cow blood, meat and milk). this low rate of disease also holds true for traditional diets that are more mixed. pollan points out:
"what this suggests is that there is no single ideal human diet but that the human omnivore is exquisitely adapted to a wide range of different foods and a variety of different diets. except, that is, for one: the relatively new (in evolutionary terms) Western diet that most of us are now eating. what an extraordinary achievement for a civilization: to have developed the one diet that reliably makes people sick!"pollan's aim with the book was to compile a list of traditional sayings and grandmotherly teachings about food and compare them with what we do know about food from science. in the process he came up with about 80 "rules" about food. he makes it clear that these are not rules we should be enslaved to, rather they should be helpful in guiding us towards the best choices for our health.
here are some of the "rules" that i particularly enjoyed:
"if it came from a plant, eat it. if it was made in a plant, don't"
"no snacks, no seconds, no sweets — except on days that begin with the letter S.” [pollan says to treat treats like treats. treats used to be expensive, and therefore infrequently eaten and highly appreciated when they were. now we have access to as many treats as we want, which leads us to indulge often without thought or appreciation. when treats are more infrequent, we will truly appreciate them and enjoy them.]
"do all of your eating at a table" [this way you will be mindful of what you eat, and make eating something that happens at a specific place and time, not just whenever]
"eat all the junk food you want, as long as you make it yourself" [he makes the point that almost anything you make will be healthier than buying it at the store. also when you make it yourself you will probably make it less often than you would buy it, and consider it a "treat", as you should]
"don't eat anything your great grandmother wouldn't recognize as food."
and, lastly, my favorite (shown in the illustration from the book, above): "when you eat real food, you don't need rules" when all you buy is healthy, whole, clean foods, you don't need rules. make whatever you want out of it, and it will nourish your body.