The 5-second rule isn't just an old wives’ tale; it has some scientific backing. Researchers put the beloved rule—alleging snacks are safe to eat if they've been on the floor for 5 seconds or less—to the test by dropping a variety of foods like pasta, sticky candy, and toast onto carpet, laminate, and tiled floors, and letting them sit on the ground for 3 to 30 seconds. The results show that the transfer of bacteria to food is immediate after hitting the floor, but moist foods, such as bologna and sticky candy, pick up 20 times more germs than dry foods, which pick up 1 millionth of the bacterial population present, according to National Geographic. Length of time sitting on the ground and the type of flooring also affect the amount of bacteria transferred. While not everyone may agree, the researchers who conducted the study say a little bacteria doesn't hurt and that they'll continue abiding by the 5-second rule when it comes to dry foods like cookies and chips.
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