You, like everyone else, have probably always assumed the “five-second rule,” which posits that food dropped on the floor is fine to eat if it gets snatched up right away, is an urban myth. Until now, the studies have backed up your skepticism.
But this week biologists at Aston University, in Birmingham, England, have released the results of a study they say proves the rule actually holds true. The researchers measured the transfer of common bacteria from various floor types (carpet, tile and laminate) onto dropped toast, pasta, cookies and sticky sweets in time periods ranging from 3 to 30 seconds, and they concluded that time was a “significant factor in the transfer of bacteria from a floor surface to a piece of food.” The type of flooring, as well as the moistness of the food, also played a role.
As it turns out, carpeted surfaces were found to be less likely to transmit bacteria onto food, whereas if you splat your spaghetti on your tiled kitchen floor and take your time scraping it back up again — uh — don’t reach for your fork.