There’s no point denying it. Most of us, at some point in our life, will have dropped a piece of food on the floor, quickly glanced around to make sure no one was looking, and gobbled it up. Because as long as you pick it up within five seconds, it won’t make you ill, right?
Well, according to new research, there is truth behind the so-called “five-second rule” (even though it has often been dismissed as an urban myth). Not only that but, for some foods, it could even be extended to half an hour.
‘Rigid’ foods, such as dry toast, biscuits and chocolate, can be left on the floor for half an hour and won’t pick up additional bacteria in this time, according to researchers at Aston University.
However, the five-second rule should still apply to foods such as pasta and sweets, which pick up more germs when left on hard floors for longer periods, reported the Daily Mail.
The scientists tested the five-second rule with different foods on various surfaces, including carpet, linoleum and tiles, which were riddled with 10 million bacteria. It's safest to eat food dropped on carpeted floors, the research suggested, as this had the lowest bacteria levels after three-and-a-half minutes. But if you drop food on a laminated or tiled kitchen floor, it’s worth picking it up quickly (or perhaps just binning it).
“People may not realise that dry foods, hard foods are really quite low-risk,” said lead researcher and germ expert Professor Anthony Hilton. “Not only do they not pick up much bacteria on impact with the floor, but they do not get any additional contamination over time.”
He added: “It is less safe to leave damper, stickier food, which pick up more after falling and more over time, so the five-second rule probably does still apply to them,” reported the Daily Mail. “However the chances of anyone getting ill from dropping food on the floor at home are infinitesimally small.”
While you can never guarantee that eating dropped food will be risk-free, chances are there’s little to worry about if it is on the floor only briefly. “Obviously, food covered in visible dirt shouldn't be eaten, but as long as it's 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.
“Our research has shown that the nature of the floor surface, the type of food dropped on the floor and the length of time it spends on the floor can all have an impact on the number that can transfer.” The research certainly provides food for thought.