Cereal Grains -- more calories, less filling

Cereal grains, historically, were cultivated in order that limited agriculture areas might supply food to support population densities not otherwise possible. They are concentrated forms of food, readily assimilated by the body, containing small residue of bulk, and so may be eaten in quantities far in excess of the calorie needs without sensation of fulness. All carbohydrate foods and most drinks fall into this category, either by virtue of their origin or the reaction of the body to them. Milk is actually a liquid infantile food, the use of which man has carried over into his adult life and which, in general, satisfies the definition of concentrated carbohydrate. -- George Thorpe, quoted by Dr Michael Eads in The Arrow #27