Trivia: The Five Seconds Rule

Scientists have actually investigated the Five-Second Rule.

The Five-Second Rule states that it's okay to eat a dropped piece of food, as long as you pick it up before you can count to five.

In 2003, a high school intern at the University of Illinois named Jillian Clarke conducted a survey and found that half the men and 70% of the women knew about the five-second rule. Jillian then conducted this experiment: first, she contaminated a ceramic tile with E. coli bacteria, then she
placed gummy bears and cookies for 5 seconds and analyzed the food: they sure were contaminated.

In 2007, professor Paul L. Dawson of Clemson University and colleagues repeated the experiment. This time, the test surfaces were tile, wood flooring, and nylon carpet; the food were bread and bologna; and the bugs were salmonella. They discovered that a) salmonella can survive for 28 days on a surface and b) in just 5 seconds, anywhere from 150 to 8,000 bacteria transferred to the food.

So what does this mean for the Five-Second Rule? Do what you like, but remember: the infectious dose (the smallest number of bacteria that can actually cause illness) is as low as 10 for salmonella and 100 for E. coli. (Source)

Hmm. I thought there was another experiment that showed it depended on how moist the food was-- an apple slice would pick up more bacteria than an M&M, say.
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But what are the odds of salmonella or E. coli being on the surface you happen to drop your food on?

There's many factors that go into my decision to follow the 5 second rule or not. How hungry am I and how much do I like the food that I just dropped? What sort of surface did I drop it on and is it the last one? It's a lot to think about in just 5 seconds.
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The problem with these studies, including Mythbusters, is that they don't stay true to the scenario:

The five second rule is for food that has dropped from a height, not been placed carefully on top of a bacteria smear.
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I would eat something after 5 seconds on my kitchen floor... but not a public bathroom floor...
Context is everything here. Even ingesting E. coli is not *necessarily* going to make you sick. And most environmental bacteria will not make you sick. Food is not sterile.
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As much as I respect High School science projects as proof of something, the method is flawed. actual floors do not have bacteria smeared on them (though any food residew left on the floor would be a fine place for bacteria to grow in the future).
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Does anyone remember reading a number of studies somewheres which actually refuted the idea that bacteria transfer to food within a few seconds, and that it actually took really long?
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Some MIT students did a study, dropping things randomly in ordinary places. Most foods tested were ok after 5 or 10 seconds, and some were still fine after a much longer time on the floor/ground. I agree that placing something on a surface smeared with a concentration of bacteria will not produce accurate results.
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Yeah, it's not so much that people follow the 5 second rule because they believe bacteria can't get into the food in under 5 seconds; it's just an arbitrary length of time that we feel psychologically comfortable with. The difference between "I dropped it" and "I'm foraging for scraps on the floor."
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Another study found that people are very willing to follow the five second rule for candy, and quite unwilling for vegetables. It's definitely psychological.

That said, it is actually good for your immune system to be challenged occasionally. They way when you DO eat contaminated lettuce, your immune system says "Big whoop, I've seen this before. No problem." The chance of getting a major, knock-you-flat bacteria or virus from a surface you are familiar with (ie: not a public bathroom or cafeteria) is low.
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I'm going to go ahead and assume my floor is home to a minimum of salmenella and continue to eat stuff off of it no matter how long it's been there. Unless it gets hair on it.
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my science fair project is about this and its more accurate.
its simple;
dont smear bacteria over the surface,
do it over somewhere that people might actually pick up off the floor and eat it.

"Tempscire" is right.
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i am conducting an experiment on this and it turns out this is very true and discusting!!!!! i will never use the five second rule,but even though i say that it may not be true because i get tempted every once in a while.:0
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