I have a lot of personal rules about food. Nearly every food item I buy comes from within a 100 mile radius of where I am at that point. Nearly every food item I buy has no genetic modification. I'm also meat/dairy free for the time being, but that's for personal dietary reasons. He gave a number of other good ones in the video, like don't eat anything your grandparents wouldn't recognize.
The problems we have come from the way the food industry has expanded -- the larger the scale, the more processed and genetically modified the foods. It all boils down to those two things.
For instance, I've seen an example of a handful store-bought strawberries being so loaded with pesticides, that they were mashed up and spread through a garden bed and worked effectively to keep pests away. Why should we be eating that?
So, I keep it pretty simple. If I am eating greens or grains, I make sure that I could make an afternoon drive to where it came from, that it's roughly when that veggie should be coming out of the ground and that there aren't pesticides. Helps that I typically go straight to a farm once a week for that. Same deal with meats though. If it's seafood, I'm not going to eat anything that comes from the Atlantic. If I buy meat, I go to a butcher who buys from a nearby rancher -- he ought to know well enough what the background behind the meat he's buying is.
I was eating fast food not too long ago and got depressed by the thought that somebody a quarter of the way around the globe was likely eating the exact same thing. Why should my diet in Oregon be exactly the same as somebody's in Georgia? Different cultures, different soils, different climates, etc.
This isn't green hippie lib stuff. It's the way your grandparents ate when they were your age.