In folklore, the five-second rule states that food dropped on the ground will not be significantly contaminated with bacteria if it is picked up within five seconds of being dropped. Some may earnestly believe this assertion, whereas other people employ the rule as a polite social fiction that will allow them to still eat a lightly contaminated piece of food, despite the potential reservations of their peers.
There are many variations on the rule. Sometimes the time limit is modified. In some variations, the person picking up the food arbitrarily extends the time limit based on the actual amount of time required to retrieve the food.
- Piece of food dropped must be retrieved within five standard seconds of hitting the ground.
- If the piece of food is not retrieved within five standard seconds of hitting the ground it must be cleaned or thrown away.
- If a piece of food is dropped a second time you must continue the count from where you left off the previous time. For example if a cracker was on the floor three seconds the first time it is only allowed two seconds the next time.
- The five second rule applies to all foods except jelly , pudding , or any liquid based food that cannot be picked up as a whole.
Scientists prove the five-second rule is no myth
( 17/03/2014) According to science the five-second rule is no myth. Offering relief to all those who have been picking their food off the floor and helping them feel a little bit less gross.
Some live by the belief that when you drop a bit of food on the floor you get five-seconds before it’s rendered too disgusting to eat. Six-seconds? No way. But for some reason five has generally been accepted.
Of course, we all thought this was a load of rubbish and only used it to convince ourselves we can still consume that meatball that’s just rolled onto the carpet. But science has proven we’ve been getting it right all along.
Biology students at Aston University in the UK monitored how quickly E.coli and common bacteria spread from surfaces to food such as toast (butter side down, no doubt), pasta and sticky sweets — with time being a significant factor in the transfer of germs.
Food picked up just a few seconds after being dropped is less likely to contain bacteria than if it is left for longer periods of time according to the findings.
The type of flooring the food has been dropped on has an effect, with bacteria least likely to transfer from carpeted surfaces and most likely to transfer from laminate or tiled surfaces to moist foods making contact for more than five-seconds.
“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,” said Professor Anthony Hilton who headed the study.
But don’t get too cocky next time you reach for a spilt bit of grub. Professor Hilton goes on to clarify:
“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; 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.”
Research into The 5 Second Rule
The five-second rule has received some scholarly attention and has been studied as both a public health recommendation and as a sociological effect.
In 2003, intern Jillian Clarke of the University of Illinois at Urbana–Champaign found in a survey that 56% of men and 70% of women surveyed were familiar with the five-second rule. She also determined that a variety of foods were significantly contaminated by even brief exposure to a tile inoculated with E. coli. On the other hand, Clarke found no significant evidence of contamination on public flooring. For this work, Clarke received the 2004 Ig Nobel Prize in public health. A more thorough study in 2006 using salmonella on wood, tiles, and nylon carpet found that the bacteria were still thriving after twenty-eight days of exposure under dry conditions. Tested after eight hours’ exposure, the bacteria could still contaminate bread and bologna in under five seconds, but a minute-long contact increased contamination about tenfold (with tile and carpet surfaces only). The five-second rule was also featured in an episode of the Discovery Channel series MythBusters. There was no significant difference in the number of bacteria collected from 2 seconds exposure as there was from 6 seconds exposure. The moisture, surface geometry and the location the food item was dropped on did, however, affect the number of bacteria.
Ted Allen put the rule to the test in an episode of Food Detectives, and found that bacteria will cling to food immediately. High traffic areas will lead to even more bacteria on the food.