The 5-second rule is a popular belief that food that has been dropped on the ground can still be safe to eat if it is picked up within five seconds of falling. This age-old adage has been around for generations and has become a common justification for not letting spilled food go to waste. But is the 5-second rule actually backed up by science, or is it just another urban legend?
In 2017, a study conducted by Rutgers University sought to answer this question once and for all. In their study, researchers examined four different types of food, including bread, apple slices, and two types of candy, after they were dropped onto a clean tile floor. The foods were left on the ground for either five, 30, or 60 seconds before being picked up and examined for any potential contaminants.
The results of the study showed that the longer the food was left on the ground, the more contaminants were found. After five seconds, the bread and apple slices had just under 10,000 bacteria cells, while the candy had nearly 45,000 bacteria cells. After 30 seconds, the bread and apple slices had nearly double the amount of bacteria, while the candy had nearly quadruple the amount. After 60 seconds, the bread and apple slices had nearly ten times the amount of bacteria, while the candy had nearly 15 times the amount.
These results suggest that, while the 5-second rule can somewhat hold true, it is not a guarantee that food will be safe to eat after coming into contact with the ground. In fact, the longer the food is left on the ground, the more potential for contamination there is.
The study showed that the type of surface the food is dropped on also plays a role in the amount of bacteria it picks up. The researchers found that the number of bacteria on the food dropped onto carpet was significantly less than the food dropped onto tile floors. This suggests that, if food happens to fall on a carpeted surface, it is more likely to be safe to consume than if it were on tile.
In conclusion, the scientific evidence suggests that the 5-second rule holds some truth, but is not a guarantee that food left on the ground is safe to eat. The longer the food is left on the ground, the more potential it has to pick up contaminants. Furthermore, the type of surface the food is dropped onto also plays a role in the amount of bacteria it picks up. Therefore, it is wise to use caution and common sense when deciding whether or not to eat food that has been sitting on the ground.