Are you a fool for following the five-second rule?

A germ expert is putting his science where his mouth is to prove the 'five-second rule' for food actually exists.

While the 'rule' is something many have lived their lives by for generations, there's been uncertainty about whether it is scientifically sound.

The AM Show's Amanda Gillies even pushes the boundaries, saying she'll sometimes eat floor food after 10 seconds.

Co-host Mark Richardson was also a fan of the rule, saying what doesn't kill you only makes you stronger.

"It's good for you to eat stuff off the ground, isn't it? I mean, you get the bacteria and stuff like that."

But he does draw a line somewhere.

"The only floor I won't eat something off is probably the toilet floor."

A group of researchers from the UK's Aston University say they've got conclusive proof your floor food is still safe to eat - and they're even set to do a taste test in front of a crowd.

Microbiology professor Anthony Hilton will prove their findings at The Big Bang Fair this week in Birmingham.

The final year biology students monitored the transfer of E.coli and Staphylococcus aureus from a number of indoor floor types - carpet, laminate and tiled surfaces - to toast, pasta, biscuit and a sticky sweet after contact was made from three to 30 seconds.

It found the longer food is on the floor, the more bacteria is transferred.

But the kind of floor makes a difference too. Bacteria is least likely to transfer from carpet and most likely to transfer from laminate and tiled surfaces to moist foods after more than five seconds.

But Prof Hilton says that's not to say there aren't extra risks in eating food from the floor.

"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," he says.

As part of their study they also conducted a survey which found the vast majority - 87 percent would or have eaten food from the floor.

Of those people, women were slightly more likely to do it than me at 55 percent and 81 percent of them would follow the five-second rule.

Last year, scientists at Rutgers University in the US performed the same tests with the same outcome - that bacteria can transfer onto food in less than one second.

It says wetter foods are more likely to pick up bacteria - researchers included watermelons in their tests which had the most contamination.

"Transfer of bacteria from surfaces to food appears to be affected most by moisture," professor of food science Donald Schaffner said.

"Bacteria don't have legs, they move with the moisture, and the wetter the food, the higher the risk of transfer. Also, longer food contact times usually result in the transfer of more bacteria from each surface to food."

However, they came to a different conclusion, saying their findings meant the 'five-second rule' myth was busted.