floor sandwich
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You can safely eat food dropped on the floor as long as you pick it up within five seconds, according to a germ expert, thus proving the so-called 'five-second rule.'

Professor Anthony Hilton of Aston University said that although eating food off the floor can never be totally without risk, the often-cited five-second rule is a pretty safe bet.

Hilton will demonstrate his theory at the Big Bang Fair in Birmingham as part of a series of national science, technology, engineering and maths (STEM) events held across the country.

"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," he told the Independent. "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."

Commenting on the forthcoming experiment, Paul Jackson, head of the fair organizers EngineeringUK, told the paper: "This is a simple example of how science is present in everyday life. From testing how safe food is to inventing new food and drink, the limits of how we can apply science and engineering are endless," Jackson added.