The Five Second Rule Started Hundreds of Years Ago

The five second rule feels like something everyone has just always known, but Dr. Keith Warriner, microbiologist, traces its actual origin back centuries, through a Mongol emperor, a 1960s TV cook, and a decades-old novel, before it ever touched a real study. Once real research got involved, the picture changed fast. Keith breaks down which surfaces in a home pick up the most bacteria, and why one specific flooring type turns out to be far worse than people assume. He also gets honest about where he personally draws the line between food worth saving and food that goes straight in the trash, based on what he actually knows about what's living on the floor. Topics: five second rule, food safety, bacteria floors, kitchen hygiene, microbiology GUEST: Dr. Keith Warriner | @‌kwarrine Originally aired on 2026-09-03