Tuesday, March 11, 2014

To Follow the "5 Second Rule" or Not?

I'm sure most of you are aware of the "5 second rule". The rule that states that food dropped on the ground will still be safe to eat if is picked up within five seconds of being dropped. So is this rule safe to follow?

Biology students and their professor Anthony Hilton monitored the transfer of the common bacteria, Escherichia coli (E. coli) and Staphylococcus aureus from different indoor floor surfaces to food items like pasta, biscuits, and sweets. The different indoor floors include tiles, laminated, and carpeted surfaces. They measured the amount of bacteria transferred from the floor to the food from 3 to 30 seconds. The result showed that time was a very important factor on the amount of bacteria transferred. The less time the food was in contact with the floor, the less bacteria it contained. They also found that what type of floor the food dropped on mattered as well. Bacteria was found to be easiest transferred from laminate and tiled surfaces compared to carpeted surfaces. 

The study also found that 87% of people surveyed would eat food dropped on the floor, 55% of those that would were women, and of those woman 81% follow the 5 second rule. The "5 second rule" that we have been following as a child may actually be reliable and safe after all. So go ahead and eat that piece of food you dropped, just make sure it's within 5 seconds of touching the floor. 

Posted by Amber Vien (6) 


  1. I am so happy that the 5 second rule is true. It certainly makes sense that bacteria take time to encroach upon the dropped food, but having the scientific proof is great. I had no idea this was actually being studied.

    Posted by Michael Dailing

  2. I think that making sure food doesn't hit the ground is important, but not as important as other situations. A good example is how long food can be left out exposed, and still be eaten. It seems like to danger from bacteria accumulating on food from the air over the course of an hour could be much worse for you than bacteria accumulated in five seconds from the ground.

  3. I always followed the 5 second rule, but I never really took the time to think just how much bacteria would actually get on the food. It's a good thing to know that the rule I've been following for so many years actually works. Do you know the statistics of men who follow this rule?

    Posted by Lindsey Janof

  4. I follow this rule but it really depends on the food and location for me. I have a serious germ problem, and there are some place that I would absolutely not comply with this notion. Some places are not as clean as they seem or as they try to tell you! I've worked in a food service industry before and was shocked to see the level of filth and lack of hygiene.

    Maxwell Liner

  5. I have heard of this rule but I did not know that there are many people would eat dropped food. But in the experiment that they conducted, do you know when is the critical point that the amount of bacteria increased significantly?

    Yim Hui

  6. The statistics of men that follow this rule was not collected during the study. It would have been interesting to compare the difference between men and women though. When food is in contact with the contaminated surface, bacteria gets transferred immediately. Therefore the quicker you pick up the food, the less bacteria it will have.
    And I agree with everyone! It definitely depends on where I drop the food. If I drop the food at home, I'd mostly likely eat it compared to if I ever drop food in a public place.

    Amber Vien