Very creative idea. I like it a lot, it is simple and effective. The zooming out thing is really a nice touch.
One critical feedback: initially you panick but then you realize that you can just move one direction at a time from one side of the screen to the other so it becomes "easy", it would be more interesting if the food was running away from you and you had to chase it. In that case you would have to change constantly buttons and coordinate yourself to follow diagonally on a different control scheme!