POV: You accidentally drop a chocolate-covered almond on the floor, and before you have a chance to *really* think about it, you pick it up and confidently pop it in your mouth. No big deal, right? Thanks, five-second rule—you striketh again.
Well, according to Trevor Craig, a food safety expert and corporate director of technical training and consulting at Microbac Laboratories, you may want to think twice about eating something that has fallen on the ground…because the five-second rule is, alas, total rubbish (pun intended).
That said: Why is it, after all those years of swearing by this unspoken “law,” that most of us haven’t actually gotten sick from eating something off the ground? According to the food safety expert, our bodies generally can fend us from most germs…but not all. Ahead we delve into why the five-second rule isn’t (totally) valid and why it’s safer (at least on paper) to avoid food that’s been potentially contaminated to prevent illness.
The five-second rule: fact or fiction?
We’ll cut right to the chase. According to Craig, the five-second rule is 100 percent fiction. “Bacteria can transfer immediately; there’s no biological rule to hold back bacteria,” Craig says. That’s to say: Contact with a contaminated surface is a surefire way of instantly (!) transferring bacteria from one place to another. “Bacteria do sometimes have capabilities to move by themselves—though it’s not like they are moving very quickly—but they are able to transfer from surface to surface almost instantly, which is critical to how bacteria and contamination occurs,” he says.
“Bacteria can transfer immediately; there’s no biological rule to hold back bacteria,” Craig says.
While we’ve been led to believe that five seconds was too short for bacteria to make its move, this definitely isn’t the case. In fact, according to the food safety expert, bacteria tends to love food just as much as we do. “Just like we need food to provide us with nutrients, energy, and water to live, so do bacteria. Most food is perfect breeding and growing potential for bacteria, and more since bacteria can transfer almost instantly between touched surfaces,” Craig says. Basically, the attraction between bacteria and our fallen food is a match made in heaven.
Of course, bacteria aren’t only found on dirty floors—or on dirty anything. It’s all around us. “Bacteria are transferred everywhere, including human bodies. The good thing about bacteria is that most of them are not dangerous, and living bodies typically have immune systems to help fight off most bacteria; in fact, some bacteria can fight off other bacteria, which is the concept of probiotics and good gut health,” Craig says.
“The good thing about bacteria is that most of them are not dangerous, and living bodies typically have immune systems to help fight off most bacteria; in fact, some bacteria can fight off other bacteria, which is the concept of probiotics and good gut health.”
TL; DR: While the majority of bacteria are harmless, there are some exceptions and types of bacteria or viruses that aren’t easy to fight off. (Because some can produce toxins that make you sick.) “Food doesn’t have an ‘immune system,’ so once exposed to bacteria, a food product can support its growth and can then pass it onto the next thing that touches or ingests it,” Craig says. (It is worth noting that some foods have bacteria, ingredients, or conditions that don’t support growth or prevent the growth of more harmful bacteria, such as certain high-acidic ingredients like vinegar.)
Okay, but does longer exposure mean more contamination?
Yes and no. According to Craig, rather than focusing on how long foods have been on the ground, you’re better off focusing on what type of exposure you’re dealing with and how long it’s been on the food itself (after contamination). “Washing off food after dropping something can remove some of the bacteria and lower the risk, but not everything can be washed, and that won’t eliminate the risk,” he says. “The longer the bacteria are on the food, the more it has a chance to grow in numbers and spread.”
Contamination can happen anywhere (not just on the floor)
Accessing the risk of cross-contamination can be tricky, so it’s important to go about it on a case-by-case basis. “Think of the surface and what that looks like and how it’s treated. You and a restaurant should be pretty good about regularly cleaning tables, and the risk should be low,” Craig says. While he notes that although you may clean the kitchen countertops frequently, it’s also a high-traffic area of your home where you handle other foods (cross-contamination opportunity) or where you put a lot of random stuff—grocery bags, purses, and mail. In short: Kitchen counters may be even more prone to contamination than other surfaces around the house.
But why do floors typically get the bad rap? Well, they’re the *most* susceptible to tons of bacteria coming from all angles. “A floor is unlikely to be cleaned as often and is exposed to everything on your feet, your family, and your pets which are probably also exposed to everything outside, and that makes its risk—and grossness—factor much higher,” Craig says.
Ultimately, the risk is yours to take (or not)
Although finding out that the five-second rule is B.S. might be shocking for many of us, it doesn’t necessarily mean that we must completely change how we live our lives…of course. Even Craig, a food safety expert (emphasis on the expert), says he may eat something that’s fallen every now and then. “I don’t always follow my own advice and have eaten things I’ve dropped at times. I’ve popped a few almonds in my mouth after dropping them,” he says. But it all depends on what it is and how he’s “treating” it after. “I’ve dropped slices of onion on the floor, washed them off, and then used them to cook.” (Of course, high temperatures can also lend a helping hand in eliminating some bacteria.)
That said, it’s important to understand that consuming anything that’s been potentially contaminated comes with risk—it’s just a matter of deciding whether or not it’s one worth taking. “It isn’t guaranteed that eating something off the floor will make you sick by any means,” Craig says. However, he still recalls the time he dropped a popsicle—it was the last one—in the park a few years ago. Craig says he of course threw it away (along with, sadly, his good mood for the day), but that he still wonders whether or not he should have five-second-ruled it. “But an ice pop? Better safe than sorry.”
