I read somewhere a while back that a pillow over two years old has accumulated it's original weight in dust mite nastiness etc.
I have to change mine regularly as my head sweats terribly no matter how cold the room is kept. I even bought one of those pillows that "guarantee" to keep your head comfortable -- no dice. Anyway, now I just get cheaper ones; use the covers that supposedly form an impervious barrier (but probable also contributes to heat), and still spend more money on them than I care to think about. The older I get, the less I seem to sleep I seem to get. Maybe I should use the money on more fabric and sleep sitting up in my recliner.... My beagles won't like it; they want to cuddle in bed. Joyce in Delaware