The Five Second Rule may be true
The age-old “Five Second Rule” might not be a myth after all, according to research out of Aston University in Birmingham, England. Microbiology Professor Anthony Hilton and a team of students have found that food picked up a few seconds after being dropped is less likely to contain bacteria than if it is left for longer periods of time.
The study tested two types of common bacteria – Escherichia coli (E. coli) and Staphylococcus aureus – and their transfer to foods from carpet, laminate, and tiled surfaces. The foods examined included toast, pasta, biscuit, and a sticky candy, with contact ranging from three to 30 seconds.
The research concludes that time is indeed an important factor in the transfer of bacteria from a floor surface to a piece of dropped food. Additionally, the type of floor material is significant, as bacteria is least likely to reach food from carpeted surfaces and most likely to be transferred from laminate or tile. Moist foods, when left to make contact for more than five seconds, were most likely to pick up bacteria.
“Consuming food dropped on the floor still carries an infection risk as it very much depends on which bacteria are present on the floor at the time,” according to statement from Professor Hilton. “However the findings of this study will bring some light relief to those who have been employing the five-second rule for years, despite a general consensus that it is purely a myth.”
Hilton added, “We have found evidence that transfer from indoor flooring surfaces is incredibly poor with carpet actually posing the lowest risk of bacterial transfer onto dropped food.”
“From my perspective, thinking in terms of duration, the longer you wait, the more likely you are to put yourself at risk,” said Dr. Hampton. “But you really should think about context, and a clean home is a safer bet than dropping something while you’re walking down the street.”
Overall, he says of dropped food, “You want to avoid it if you have an option.”
Dr. Hampton also brings up a related issue—general food storage—about which he believes some people might not be well informed.
“Many people store food based on their experience with seeing food left out for long periods of time,” said Dr. Hampton, adding that “things grow rather quickly outside of a refrigerated environment.” This means as a basic rule, food should be placed back in the fridge as soon as possible after it is served, and removed again later if needed.
If you do not have this type of control, Dr. Hampton says, ask questions to make sure food you plan to consume has been stored properly.
As a final word on food and bacteria, Dr. Hampton asks “why put people in harm’s way when you have the opportunity not to?”
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