Odor that mysteriously goes away

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My boyfriend left work in the morning smelling like onions. His armpits were so foul that it had stunk up the room. He comes home at night with no smell whatsoever. He says he doesn’t know why that happens. Is this possible? Is it possible for the smell to just magically go away on its on without having to shower?


Hi Len, interesting story, but yes, that can happen. There are two possible explanations. 1/ The odor precursors are gone; there are fewer sulphuric compounds secreted with the sweat. Or 2/ more likely, the bacterial composition changed in the course of the day. An onion smell usually stems from Staphylococcus hominis. They can become overruled by other bacteria at some point. The average doubling time of bacteria is 1 to 5 hours. In one experiment we did, we had a strain of Staphylococcus hominis that took about 19 hours to double. This strain get easily be overruled by other bacteria that grow much faster. So over the course of the day, this strain is depleted, while other strains took over. As such, much less onion smell will the result. Best, Chris