Do you ever eat food that's fallen on the floor? Adherents of the "five second rule" certainly do, but a new study suggests that more bacteria may stick to certain items than previously thought.
Researchers at Manchester Metropolitan University examined cooked pasta, ham, a biscuit, bread with jam and dried fruit that had been dropped on the floor for various lengths of time. The products were chosen because they're common, everyday items and contain different levels of water, which sustains bacterial growth.
According to The Daily Mail, the study found that foods with higher salt or sugar contents were less likely to pick up harmful bacteria:
Both the ham, a salty product, and the sugary bread and jam fared well in the test. When retrieved from the floor within three seconds, the foodstuffs showed little sign of bacterial growth. The dried fruit and cooked pasta, on the other hand, showed signs of klebsiella after three seconds - a bacteria which can potentially lead to a wide range of diseases such as pneumonia, urinary tract infections, septicaemia and soft tissue conditions.
The dried fruit picked up dangerous bacteria in five seconds, and the pasta in just three.
Several studies have been conducted testing the five second rule, but our favorite is a more informal one carried out by Discovery's "Mythbusters" television program, which found that there was no significant difference in the number of bacteria that clung to an item over the course of two seconds than did over six seconds.