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Designing your own experiment to debunk the ‘five-second rule’

Science education writer and resident scientist Bethany Brookshire tests whether the five-second rule is really true. Photo courtesy of Society for Science & the Public/Eureka!Lab.

We’ve all been there. You’re excited to take a bite out of your lunch, but then it drops on the floor. You quickly pick it up, but — is it safe to eat?

In Eureka!Lab’s second DIY Science video, science education writer and resident scientist Bethany Brookshire puts the five-second rule to the test. Bethany finds that bacteria don’t really wait for the count of five. If food has fallen, it probably has microbes all over it.

The video and accompanying blog posts walk you through how to design an experiment, grow your own microbes, and analyze results to test whether food left on the floor for only five seconds picks up fewer microbes than food left longer.

View the video below:

Read the blog posts:

Happy experimenting! And hang onto your food.