Commonly the rule is simply extended to however many seconds is necessary to declare the food still edible (ex: 20-second rule).
Food god: Hurry, pick it up. 5 second rule!
~5 seconds later~
Food god: I am angered! I shall infest your sandwich with cooties!!
"Dude, that's been there for 3 days."
"But I just saw it, like, 3 seconds ago. 5 second rule yo."
A popular axiom that deems food dropped onto the groud edible for a period of 5 seconds immediately following its release. Does not apply to porous or otherwise absorptive foods such as frosted cake or ice cream.
-Nah, it's O.K. Five second rule!
Hot Girl:Hey! Are you listening to me!
Guy:Oh! I'm sorry babe 5 second rule.