Ask The Nurse: Is the "5-Second-Rule" Really Safe?

dropped food bacteria

Dear Nurse Chris: My husband grew up in a family that allowed the “5-second rule.” If you dropped food on the floor, but picked it up in less than five seconds, it was OK to eat. I know it’s crazy, but can I give him – and our two sons – some evidence that the “5-second rule” is terrible?  Rosa in Mundelein

Dear Rosa: The 5-second rule was not used in our house; if it fell on the floor it was tossed out. Thank goodness our bodies are made the way they are, because the hydrochloric acid in our stomachs has saved us from many an illness.
There’s good science for this view. Tell your family to listen up:  it's probably not even safe to follow a 1-second rule. The transfer of bacteria from a contaminated surface to food is almost instantaneous - or, at the very least, quicker than human reflexes.

In a recent study, Clemson University food scientist Paul Dawson and students contaminated several surfaces (ceramic tile, wood flooring, and carpet) with Salmonella. They then dropped pieces of bologna and slices of bread on the surfaces for as little as 5 seconds and as long as 60 seconds. After just 5 seconds, both foods had already picked up as many as 1,800 bacteria (more bad bugs adhered to the bologna than the bread). After 60 seconds, it was up to 18,000 bacteria!

There are 76 million cases of foodborne illness annually in the United States, according to the Centers for Disease Control - so unless you're the only family on the block that sterilizes your floors hourly, stop eating dropped food. "Let's not forget what comes into contact with floors--people bring animal feces on their shoes into their homes," Dawson said.

And don't assume that countertops are clean. Dawson's team also found that the Salmonella actually survived as long as four weeks on the test surfaces.

I am also a stickler about hand washing. Many potential illnesses can be avoided when washing hands with soap and water. Hand washing before meals, after using the restroom, after playing outside, after coughing and blowing your nose, before preparing food and after touching food (such as raw meat) are some of the ways to avoid getting sick.