Researchers at the University of Ghent in Belgium asked eight test subjects to stop using deodorant or antiperspirant for a month.
Another subject who did not regularly use either was asked to use deodorant for a month. The timeframe was selected because it takes around 28 days for a new layer of skin cells to form.
The armpit bacterial community of each subject was tested at the start and the end of the month, and the results showed that each armpit ecosystem had been altered, 'Science Alert' reported.
Researchers found that antiperspirant use was linked to an increase in Actinobacteria, the 'bad' type of armpit bacteria that instigate noxious armpit odour.
Lead author Chris Callewaert told 'Real Clear Science' that the aluminium compounds in antiperspirants, which can block pores to prevent sweating, may be to blame, by killing off "good" bacteria and allowing Actinobacteria to dominate.
The study found that deodorants which lack these sweat-blocking antiperspirant compounds are actually linked to a slight decrease of stinky Actinobacteria.
The results were published in the journal Archives of Dermatological Research.