According to the so-called five-second rule, it’s safe to eat food after it’s dropped on the floor—at least as long as you do so within five seconds. It’s one of those “rules” that has stood the test of time, as proven by its steadfast presence in everyday culture. In fact, you’ve probably seen your fair share of people swear by the rule. But is it real? Here’s what you should know about the five-second rule for food, according to experts and science.

The Origin of the Five-Second Rule
The rule mostly stems from urban legends. One such story can be traced back to Genghis Khan, founder of the Mongol Empire. Allegedly, Khan established the “Khan Rule” at banquets: If food dropped on the floor, it could stay there as long as he permitted. Several centuries later, chef and television personality Julia Child may have further contributed to the myth. In a 1960s episode of The French Chef, Child flipped a pancake only to have it land on the stovetop. She then returned the pancake to the pan, noting that you can always pick it up if you’re alone in the kitchen.
Although these stories don’t explain why five seconds became the magic number, they do shed light on how people may have learned to handle dropped food. But when it comes to safety and the risk of germs, does five seconds actually make a difference?
Ultimately, the Five-Second Rule Is a Myth
Unfortunately, there’s no truth to the five-second rule. When food falls on the floor (or any surface, for that matter), its level of contamination is mainly determined by the “dirtiness” of the floor, rather than the length of contact. In other words, food that falls on a germ-ridden floor will pick up germs, regardless of how long it stays there. Food scientist, Paul Dawson, has even tested the five-second rule in a lab. To do this, he and his team contaminated tile, wood, and carpet with Salmonella bacteria, one of the most common causes of food poisoning. Next, they dropped bologna (moist food) and white bread (dry food) onto the surfaces, then waited for five, 30, and 60 seconds. The team then measured the number of bacteria on each food for each time frame. According to Dawson, high levels of bacteria were found on both the bologna and white bread, regardless of the surface and contact time. And while there were some differences (like less bacteria on dry foods or foods that touched the carpet, for example), there was still a noteworthy degree of contamination across the board.
Bottom line: If food drops onto a surface, it will pick up germs from said surface. The length of contact time doesn’t influence whether or not this happens, and ultimately, the risk of food poisoning.
Article by Kirsten Nunez Kirsten Nunez for Martha Stewart Living©
Source: The Truth About the Five-Second Rule for Food: Here’s What Science Says About the Popular Maxim (msn.com)