I've basically cut out breads and high-carb foods, such as potatos, chips, etc. and mostly processed stuff out of my diet. I'm not "low-carbing" so to speak, but I am trying to fill the empty hole in my diet with more veggies and fruits. I don't miss bread, rice, and pasta, pretty much at all. I will, on the weekend, eat a little of those things, but I'm getting to where I don't even want them on the weekend. My next step is to actually cut calories.
I've tried getting rid of sugar in my drink, but I started using Splenda, only to find out I was allergic, so now I'm weaning myself onto sugarless beverages..... THAT'S what I'm going to miss.....
I've got cousins doing "Atkins" diets. They don't seem to understand that after a certain point, you add in more carbs, either. It's a shame, because the end diet from the book, is actually pretty sane.
As far as grains go. I learned in anthropology, that a lot of diseases, including tooth decay, were only found in humans, AFTER grains were incorporated in the diet. There are some interesting things to read about it.
One site, that I'm not finished reading, but is somewhat topical:
Evolutionary Discordance of Grains/Legumes in the Human Diet