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Is the 5-Second Rule true?

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If we pick up dropped food quickly, is it still safe to eat? How quickly does bacteria on the floor move to the food? Some people call it the “5-Second Rule” or the “10-Second Rule,” even the “2-Second Rule.” But is there any truth to it, or is it just something we say to allow us to eat food off the ground? Vsauce investigates.

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Food retrieved just a few seconds after being dropped is less likely to contain bacteria than if it is left for longer periods of time. However, the type of food and the type of surface greatly impacted the bacteria transfer. Moisture drives the transfer of bacteria from surface to food; the wetter the food, the higher the risk of transfer. Looking at the surfaces, tile and stainless steel had the highest rates of contamination transfer. Somewhat surprisingly, carpet had the lowest rate of transfer, and the rate was variable on the wood surface.

Food safety is a major health burden in the United States. The Centers for Disease Control and Prevention estimate that every year, one in six Americans (roughly 48 million people) get sick from foodborne illness, 128,000 are hospitalized, and 3,000 die.

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