Imagine you've spent your last 10 yuan on a pair of fragrant, spicy chicken wings, ready to enjoy them with glee, when—bam!—the bag holding them accidentally falls to the ground. Your heart is broken. You instinctively look around—no one's around! So do you pick them up immediately and pretend nothing happened, or do you painfully toss them in the trash?
Of course, for most people, once food has hit the ground, they definitely wouldn't want to pick it up and eat it. But you only have these 10 yuan left! And you haven't eaten all day! Think about it, these spicy chicken wings are still steaming hot. Are you going to pick them up, or are you going to pick them up?
Your concern, well, is obviously that it looks and feels dirty. Think about it, how many pairs of shoes have walked over the spot where those wings lay? They might have been in the bathroom, they might have stepped in dog poop. Salmonella, E. coli, and other bacteria that cause various diseases might have already crawled onto the surface of the chicken wings.
Is the 5-second rule reliable?
In 2007, Dr. Paul Dawson of Clemson University in the United States published a study in the *Journal of Applied Microbiology* that debunked the reliability of the 5-second rule. He dropped sausage and bread onto tile, carpet, and wood flooring contaminated with Salmonella, leaving the food on the surfaces for 5, 30, and 60 seconds respectively, and recorded the amount of bacteria transferred to the food at different times.
The results showed that the amount of bacteria transferred to the food largely depended on the surface area of the food that was contaminated. The material of the floor also had an impact. For example, food dropped on carpet transferred less bacteria, less than 1%. But when food came into contact with bacteria-laden tile and wooden floors, within 5 seconds, 48% to 70% of the bacteria were transferred to the food.
All of this shows that whether food is contaminated by bacteria has nothing to do with how long it has been on the ground.
So, do you have to painfully give up those spicy chicken wings? Hold on, young friend. Even so, Dr. Dawson frankly stated that even if your food is covered in bacteria, so what? If you eat it, nothing will happen to your body! Because very few of the bacteria on it are pathogenic.
Recently, Mike Meacham, an engineer at NASA, conducted another experiment that confirmed the "5-second rule" is true. However, the prerequisite is that the side of the food that fell to the ground is dry.
Only when the food that fell is wet, or the floor is wet, will eating it actually cause problems. This is because E. coli, Salmonella, and Listeria all love moist environments; they absorb the nutrients they need from water and then grow and multiply.
Once wet food has been on the ground for more than 30 seconds, the amount of bacteria it picks up will be 10 times more than food that was picked up after being on the ground for just 3 seconds.
Similar to Dr. Dawson's experimental conclusions, this study also found that the type of surface the food falls on is very important. Generally speaking, food falling on carpet or a blanket is better than falling on linoleum, because the contact area between the food and the carpet or blanket surface is smaller than with linoleum, which means the rate of bacteria spreading to the food will be slower.
Women are more inclined to eat food that has fallen on the ground
Surprising, isn't it?
The first person to statistically compile the 5-second rule was high school student Jillian Clarke from Illinois, USA. Her research report stated that among the people surveyed, 70% of women and 56% of men were familiar with the 5-second rule, and women were more likely to eat things that had fallen on the ground.
Aston University in the UK also conducted a survey and found that about 87% of respondents believed in the 5-second rule, 55% of whom were women.