The Science Behind The Five Second Rule And Other Food Myths

Nov 16, 2018

Students use the scientific method to learn about the bacteria levels in beer pong, on menus, sharing popcorn and other common activities that spread germs.
Credit courtesy of Paul Dawson

The mere mention of the five second rule conjures up images of all the kernels of popcorn, slices of pizza, and peanut M&Ms that hit the floor without warning. And then there is the mental debate that followed: Is it safe to eat? How dirty is this floor? Is there any hair on it? But it’s the last slice!

Microbiologists Paul Dawson and Brian Sheldon tackle the science behind the five second rule and other food myths in their new book “Did You Just Eat That?: Two Scientists Explore Double-Dipping, the Five-Second Rule, and Other Food Myths in the Lab" (W.W. Norton and Company/2018). Dawson is a professor of food science at Clemson University and Sheldon is a professor emeritus in food microbiology at North Carolina State University.

The two share how they engaged undergraduate students in research to debunk food myths. They join host Frank Stasio to give timely tips on avoiding salmonella, colds and flu this season. They also share their research on some burning questions: is it better to use hand sanitizer or soap? Is it really that bad to double dip your chip? How dangerous is it to share food with someone?