I've been doing an experiment. 

For the last 2 weeks my diet has been - almost exclusively grains. Bread, pasta, rice has been the mainstay. Grains are defiantly addictive. There is something going on in the brain when I eat it. 

The effects has been as pronounced as I thought but I do feel like shit. I have less energy and I am more sedentary. Grains (gluten especially) seems like the perfect slave food.