Me Too!

I’m a Doctor. If I Drop Food on the Kitchen Floor, I Still Eat It.

I first became interested in the five-second rule years ago, when I was a co-author of a book on medical myths. We cited a number of studies showing that food that touched household surfaces — even for brief periods of time — could pick up bacteria or other harmful substances.

This most recent study was similar in that it tested a variety of foods, a variety of substances, for various periods. And, like those other studies, this one found that food touching the floor, even for a very short amount of time, could pick up bacteria.

There’s no magic period of time that prevents transmission. But even though I know bacteria can accumulate in less than five seconds, I will still eat food that has fallen on my kitchen floor. Why? Because my kitchen floor isn’t really that dirty.

Our metric shouldn’t be whether there are more than zero bacteria on the floor. It should be how many bacteria are on the floor compared with other household surfaces. And in that respect, there are so many places in your house that pose more of a concern than the floor.

I'm a doctor, too (a doctor of oceanography) but my experiences in basic microbiology convinced me early on that the best way to live in a dirty world was to have an active immune system created by challenging it with normal environmental bacteria.