I remember being a little bit surprised the first time I heard of the five-second rule as a kid. It wasn’t because I’d been raised in some fastidious, hyper-germ-conscious family – in fact, it was kind of the opposite: In my house, the rule was always 30 seconds. Unless you’d somehow managed to fling your bagel across the room, odds were good you could scoop it up before the deadline.
Call it gross, but rarely did food go wasted because of clumsiness. Besides, scientists recently poked a hole in the five-second rule: While they did find an overall connection between time on a contaminated surface and bacterial transfer, there were some cases where it happened almost immediately — certain bacteria made their way from floor to food in less than a second.
Five seconds, in other words, is kind of an arbitrary upper limit. And in a New York Times column yesterday, physician Aaron E. Carroll, a professor of pediatrics at the Indiana University School of Medicine, argued that all the focus on the five-second rule kind of misses the point: When it comes to how we handle food, we fixate on the floor while while engaging in other, much grosser behaviors.
“Our metric shouldn’t be whether there are more than zero bacteria on the floor,” Carroll wrote. “It should be how many bacteria are on the floor compared with other household surfaces. And in that respect, there are so many places in your house that pose more of a concern than the floor.” In one 1998 study in the International Journal of Environmental Health Research, scientists swabbed a bunch of indoor surfaces, including several beyond the kitchen, with some counterintuitive results:
They found that the kitchen floor was likely to harbor, on average, about three colonies per square inch of coliform bacteria (2.75 to be exact). So there are some. But here’s the thing — that’s cleaner than both the refrigerator handle (5.37 colonies per square inch) and the kitchen counter (5.75 colonies per square inch)…
I know a lot of people who are worried about the toilet seat, but it’s cleaner than all the things in the kitchen I just mentioned (0.68 colonies per square inch). What’s dirtier in the bathroom? Almost everything. The flush handle (34.65 colonies per square inch), the sink faucet (15.84 colonies per square inch) and the counter (1.32 colonies per square inch).
Carroll also added a friendly reminder that just about everything you touch is crawling with germs. It’s not just surfaces. Your phone, the bills in your wallet, your laptop keyboard — all things you may handle before eating without a second thought — are bacterial hotspots, too. The moral of the story: Keep things in perspective, wash your hands, and stop worrying so much about picking your fumbled bagel off the floor. Unless it lands spread-side down, in which case, best to just let that one go.