Sorry, I didn't realize the same post had been put up twice and I answered both of them.......let's just stick with one of them.
I believe that the paleo diet did not originally involve grains. Grains were not introduced into our diet until agriculture came into being. Most people where "hunter/gatherers" so they ate only what they could find seasonally.
Of course, the closer you get to fresh food, the better it is for you; that's why we recommend that you shop around the "outside walls" of your grocery store. If you think about where things are placed, you will notice that fresh fruits/veggies, fresh dairy, etc are along the outside walls. The closer you get to the center of the store, the more processed will be the food you find.
A lot of processed food has had the vitamins/minerals removed, then replaced during processing. Much better to have the fresh, intact vitamins/minerals. Even with the grains -- the closer to "whole" they are, the better for you.......