The “five-second rule” of food hygiene states that any food dropped on the floor is still safe to eat, provided that it is picked up within five seconds. Maybe you’re thinking that this common piece of playground wisdom is just a silly line of inquiry, but food safety is a major health burden in the United States. And this is a rule that people actually follow so, from a public health standpoint, it is important to know whether or not it holds any truth! In today’s episode, dedicated to all her fellow germaphobes out there, Bronwen looks at what the science has to say on the matter, whether the length of time, the wetness of the foodstuff dropped, and the nature of the floor surface influence the outcome, and contemplates what this rule says about our human nature. Tune in for a slightly icky but thoroughly illuminating investigation into the five-second rule and find out why you should definitely think twice before eating off the floor!

Key Points From This Episode:

• Hear the statistics about food-borne illness in the US, according the the CDC.
• Learn more about the simple or single-celled microorganisms known as bacteria.
• The difference between harmful bacteria and good bacteria, which we need to survive.
• Some fast, fun, and freaky facts about bacteria, including how much bacteria is on your desk.
• The relationship between saying “five-second rule” out loud and its effectiveness.
• The origins of the rule, which trace back to Genghis Khan in the 14th century.
• How the much-loved Julia Child perpetuated the idea that food that looks okay is okay to eat.
• What science has to say about the five-second rule, according to a University of Illinois study.
• A study by Clemson University that concluded that length of time does, in fact, matter.
• The Connecticut College finding that the five-second rule was more like the 30-second rule.
• How a Rutgers University study debunked the five-second rule, also highlighting the relevance of the structure of the floor surface.
• What influences the microbiological composition of your floors and why you should never eat off the sidewalk.
• What food psychologist, Thomas Shipley, has to say about your ability to assess food risk.
• Find out why it’s known as the five-second rule, not the seven or 15-second rule.
• Discover why beer pong is so disgusting, thanks to the authors of Did You Just Eat That?
• Why the five-second rule isn’t bound by the constraints of practicality or public interest.
• What it has to say about human desire and the reckless pursuit of something forbidden.
• Examining the five-second rule through the lens of the law of scarcity and human psychology.
• Hear which US politician would eat a chip off the floor and why floors that look clean aren’t necessarily clean.

Links Mentioned in Today’s Episode:

‘If You Drop It, Should You Eat It? Scientists Weigh In on the 5-Second Rule’

‘Residence time and food contact time effects on transfer of Salmonella Typhimurium from tile, wood and carpet: testing the five-second rule’

‘Longer Contact Times Increase Cross-Contamination of Enterobacter aerogenes from Surfaces to Food’

Did You Just Eat That?

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