Answer:
The warmer I am the fresher I am.
What tastes better than it smells?
What goes up and down but does not move?
I am quick when I'm thin. I am slow when I'm fat. Wind is my worst nightmare. What am I?
I don't live within a house nor do I live without. Most will use me when they come in and again when they go out.
Give it food and it will live, give it water and it will die.