>Why did we ever get the idea that if our digestive system is not processing
>correctly it would be improved by giving it more to process?


    In my experience, the best thing to relieve general pain from illness is
massive amounts of food.  Of course, this works better for head-aches than
stomach aches, but, as a rule, I throw up when my stomach is empty, and keep
stuff down when it's full, in defiance of common wisdom.