"5-SECOND RULE"

Jillian Clarke was a Chicago high school student when she investigated the "5-second rule" that states if food falls to the floor for fewer than 5 seconds, it is safe to pick it up and eat it.

She found, in a survey, that 76 percent of U.S. women and 56 percent of men were familiar with the 5-second rule, and used it to justify picking up and eating dropped treats, or letting their children do so.

Clarke swabbed floors at the University of Illinois and found them surprisingly clean of microbes, thus justifying the rule.