If you’re reading this, chances are

you’ve heard of the “5-second rule,”

the urban legend that says that any

food dropped on the floor is still germ-

free as long as it’s picked up within 5

seconds. But how much truth is there

to the 5-second rule? Is it fact, or

complete fiction?

According to a study by an Aston University

research team, the 5-second rule is something

that adults believe in just as much as kids:

• 87% of people surveyed said that they

would eat food that has been dropped on

the floor.

• 55% of people who answered “yes” to

the previous question were women; 81%

of women interviewed said they would

use the 5-second rule to determine

whether or not something dropped on

the floor was still safe to eat.1

We’ve all been there before – a nice

hot piece of toast, or a clean fork, or

some other once-clean food item or

dining accessory drops on the floor, and

we snatch it back up, look for obvious

signs of dirt or other contamination,

and then immediately start trying to

rationalize why it’s still OK to put it in

our mouths. The simple fact, however,

is that once a food item touches the

ground it has absorbed bacteria and

germs, no matter how short a time it

sits there.

Scientific consensus on the 5-second

rule says that when a piece of food hits

the ground, some amount of bacteria

has already been transferred.2 Still,

food that is one with the ground for

only a short period of time will likely

have less bacteria than food that sits

on the floor for longer. Whether or not

something should still be eaten after

hitting the floor depends largely on

what kind of food was dropped, how

clean the floor is, and a little bit of

common sense.

One of the biggest factors at play in the

transference of bacteria is the consistency of

the food item in question. If picked up (very)

quickly, a dry or non-sticky food item (chips,

cookies, etc.) is not likely to have picked up

much bacteria. Moist or sticky foods, on the

other hand, will have absorbed much more

bacteria in the short time they’ve been on

the floor. This includes meats, buttered toast,

and other foods with a permeable or soft

surface to which bacteria can stick.

The kind of flooring material a piece of food has been dropped on also matters. According

to the Aston University study, carpet is the surface least likely to transfer bacteria.1 The

types of flooring that are the most likely to contaminate a food item are tile, wood, and

other laminated surfaces.3 This is especially true for laminated surfaces in high foot traffic

areas and public spaces.

A study by the University of

Arizona identified nine different

species of bacteria living on

people’s shoes – including kinds

that can cause eye, lung, and

stomach infections. The same

study also found that these

bacteria were more likely to live

longer on the bottom of shoes

than on any other surface, and

that 90-95% of said bacteria could

eventually transfer to a tile floor.2

Whether or not you believe in the 5-second rule – and science says that there’s reason to

believe it’s (at least partially) true – the best safeguard that can be taken against

contaminating food is to keep floors as clean as possible. This is especially true for schools

and other public places, where children are more likely to eat food that has hit the ground,

and where the chance of contamination is high.

Performance Systems Janitorial offers great deals on new and refurbished cleaning and janitorial

supplies to schools, office buildings, and cleaning companies. PS Janitorial’s cleaning supplies and

equipment, including floor sweepers and walk behind floor scrubbers, help keep floors clean, and food

safe to eat. For more information and to view our inventory, please visit www.psjanitorial.com.

1. http://www.aston.ac.uk/about/news/releases/2014/march/five-second-

food-rule-does-exist/

2. http://www.thecleanerhome.com/blog/flooring-blog/

3. http://www.scientificamerican.com/article/fact-or-fiction-the-5-second-rule-

for-dropped-food/