According to the Christian Science Monitor, a British microbiologist claims it is! He says an experiment he conducted showed that as long as you pick it up really quickly, food that's fallen to the floor is still safe to eat.
The researcher says he looked at cases of children and teenagers eating food following the five-second rule and they didn't seem to throw up because of it.
However, not all scientists agree.
Read more on the Christian Science Monitor's website.
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