When you accidently drop a piece of food on the floor, you get stuck in a dilemma- pick it up and eat or not! If we find that no one is watching us, we usually tend to eat the fallen piece citing the guideline ‘five second rule’ which says it’s okay to eat the fallen food if you pick it up within five seconds. But is this so called ‘five second rule’ universally proven or just a myth that could turn harmful if believed to be true? Let’s read on to find out the reality!
The five second rule essentially says that if a food item spends just a few seconds (<=5 seconds) on the floor, dirt and bacteria won’t get enough time to contaminate it and it can still be eaten without any harm to the body. Of course, the rate of contamination depends upon how clean or dirty the floor is and how many bacteria can transfer from the floor to the food. A floor that has not been mopped for weeks may be a good contender for a zero second rule where the food goes into the bin.
While the “five-second rule” might not seem like an issue for food scientists to address on immediate basis, it’s still worth investigating food myths like this one because they shape our beliefs about when food is safe to eat.
Where did the five-second rule come from?
The five second rule may have originated from a well-known fake story about chef Julia Child. Julia had once accidently dropped a piece of chicken (or a lamb depending upon the version of the story) on the stovetop and then put it back in the pan saying that small slip ups in the kitchen were permissible and if no one’s in the kitchen cooking with you, your guests would never know!
In fact, it was the piece of chicken that fell on the gas stove and not the floor and usually a stove top is significantly cleaner than the kitchen floor. This incident was believed to be the origin of the rule. Or maybe the five second rule was originated based on accumulated years of human experience where cleaning the food and making the most of it was more valuable than simply throwing the food away.
The five-second rule has actually been put to scientific test by the researchers at Clemson University. They performed a study to measure whether the length of time food comes into contact with a contaminated area had an effect on the number of bacteria that made it onto the food. To do so, the team inoculated different floor surfaces (tiles, wood and carpet) with bacteria and then placed food on the tiles for 5, 30 or 60 seconds. The bacteria levels were then measured. The end result was that the bacteria transferred was more dependent on how dirty or covered with bacteria than how much time was spent on the surface. Surface did make a difference, with carpet having less than 1% of bacteria transferring, as opposed to 48% to 70% of bacteria transferring for tile and wood surfaces.
So is the five second rule valid? Not anymore. There are thousands of bacteria and germs everywhere around us and even if the environment is clean and bacteria are less likely to transfer over to your food, eating it could still make you sick.
The moral of the story? Use your own common sense. Follow the five second rule at your own risk. Occasionally eating food that was briefly on the floor is less likely to make you sick. But it depends on what you drop and where.