Let’s be honest, we’ve all picked up a piece of food from the floor after dropping it and eaten it. But, the jury has long been out about the safety of the “five second rule,” which states that if you pick food up quickly enough, it’s still edible and will do you no harm.
Researchers at the University of Aston, in Birmingham, UK, claim they’ve found that the five second rule might, in certain instances, be safe and it could actually be extended to half an hour.
Germ expert Professor Anthony Hilton from Aston University claims the rule depends entirely on the nature of the floor surface and the type of food dropped. “Obviously, food covered in visible dirt shouldnt be eaten, but as long as its not obviously contaminated, the science shows that food is unlikely to have picked up harmful bacteria from a few seconds spent on an indoor floor,” says Hilton.
Of course, eating food that’s spent any amount of time on the floor can never be entirely risk-free, says Hilton. But, there are other factors to bear in mind when considering what to do after dropping our delicious snacks on the floor.
The researchers claim that the length of time spent on the floor isn’t a factor in the bacterial transfer for dry foods. They tested the theory using using different foods on indoor floor surfaces containing 10 million bacteria, including carpet, linoleum and tiles. The report, emailed to Mashable, revealed that dry foods like biscuits, chocolate, crisps and even sandwiches can be eaten from the floor after spending 30 minutes (yes, minutes!) on a tiled or laminate floor, with little increased risk of germs.
But, when it comes to moist foods like pasta, fries, doughnuts, or toast that falls buttered-side down, the five-second rule is still worth sticking to as moist foods transfer more bacteria from the floor if left for more than five seconds.
These new findings are a stark contrast from the overwhelming majority of studies published on the five second rule. In 2016, researchers at Rutgers University claimed to have “debunked” the five second rule, warning that eating food off the floor isn’t safe. According to the research, transfer of bacteria can begin in less than one second for certain types of food or surfaces. But, the research also found that the type of the surface and the food play an important role in bacterial transfer, echoing the findings from Aston University.
Next time you’re weighing up how badly you want that slice of toast that’s face down on your kitchen floor, think about the surface of your floor as well as how dry or moist your food is.