How To Safely Eat Fallen Food With The 5-Second Rule

Who among us hasn't quickly reclaimed a floor cookie when no one was looking? If nobody's seen: it didn't happen and it's not dirty. Well, not quite.

A new study out of Manchester Metropolitan University has come up with a more nuanced iteration of the fallen food rule. Because, if you're going to do it, you might as well know with which foods you'll be safe(er).

The food sciences researches looked at five test foods -- bread with jam, cooked pasta, a slice of ham, a plain cookie and dried fruit -- which were left on the ground for intervals of three, five and 10 seconds. These commonly eaten foods were selected because of their variance in water-activity level -- water being a key factor in bacteria growth.

What was found

• Foods with a high salt or sugar content, like many processed foods, were less likely to pick up harmful bacteria in so short a period of time. The ham (high salt) and sugary bread and jam were both considered safe, with little sign of bacterial growth, when retrieved after three seconds on the ground. The jam's high sugar content made the slathered slice inhospitable for bacterial growth.

• The cooked pasta and dried fruit, however, both tested positive for klebsiella, a bacteria known to cause a range of diseases and infections, as well as soft-tissue conditions. (Surprising. You'd think filth and germs would be more likely to stick to wettish ham, as compared to dried fruit. But it's the salt and nitrates in the ham, a preserved meat, that protect it from growth of most bacteria.)

• The dry cookie was also relatively well off -- after three, five and 10 seconds -- because of its low water activity level and "adhesion ability".

What this means

Foods made to withstand nuclear war -- processed, packaged foods -- are a safer, sugarier, saltier bet. As are cured foods, like ham -- which were prepared this way, historically, to keep over time unrefrigerated. Makes sense. [DailyMail via Foodbeast]

Image: Jiri Hera/Shutterstock

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    I eat food off the ground all the time, using a very elastic time-based rule. I've eaten lollies that could have been there for weeks. I also ate half a sausage out of a garbage bin at my nephew's engagement party, something his siblings are quick to remind me of, even though it couldn't possibly have been in the bin for more than half an hour.

    I never eat anything liquidy off the floor. Jam or honey etc seems to have a hight tenancy to attract dirt and dog fur

      I hope you're collecting good rent off that jam tenancy.

    I'd think my main concern would be various ground diets and dust bunnies. Surely the germ / bacteria would be a pretty much instantaneous transfer, I can't imagine the germs running across the floor to climb all over a tasty morsel. Anyway, I think people can be *too* clean nowadays, if you live in a germ free bubble *something* will kill you the first time you step outside !!

    Diets = dirts (Damn you autocorrect!!)

    If you just shove it in your mouth does it matter what it is? I mean you're probably ingesting a modicum of bacteria as it's not like you've taken the food off the floor and put it in the fridge to eat at a later date, thereby incubating bacteria and multiplying chances of sickness.

    See, most food was either grown in the dirt, raised on the dirt, and some probably even fed dirt.

    Just eat the god-damned food off the floor.

      ...because your floor is covered in farm soil?

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