Fact, fiction and the 5-second rule

When you drop a piece of food on the floor, is it really OK to eat if you pick up within five seconds? This urban food myth contends that if food spends just a few seconds on the floor, dirt and germs won’t have much of a chance to contaminate it./ Paul Dawson , CNN. More here .

Question: Do you eat food you drop on the ground? What’s your “-second” rule?