Anecdotally, it absolutely does - I had chalked it up to increased airflow, similar to optimizing airflow in a computer case - the exit fan position optimized to remove hotter air, the inlet pumping in cooler air wherever I'm sitting.
'One (!) slice of white bread is easier on the body than one slice of full corn bread...'.
A. By what metrics are you measuring 'easier on the body'.
B. What corn bread and what white bread?
I'm somewhat skeptical of this as a generic claim, though since it will very much depend on the recipe used (for both kinds of bread), it's certainly probable in many cases.