Brushing the tongue when brushing your teeth has been touted as a cure for bad breath caused by bacteria that form on your tongue. This cleaning of the tongue is supposed to both improve bad breath and lessen the risk of infection in periodontal openings while reducing bacterial population. While the process seems fairly benign, there are possible side effects from brushing improperly or too harshly. A May 2003 study by the Department of Periodontology, Academic Centre for Dentistry, Amsterdam, the Netherlands reported on by Wiley Interscience concluded there was reduced coating and increased sense of taste after brushing, but only minor lessening of bacteria on the tongue surface 1. But the Vol. 134, No. 1 of the Journal of the American Dental Association states that brushing the tongue can reduce bad breath by as much as 70 percent.
Prolonging Bacterial Presence
Tongue brushing can result in pressing bacteria further into the tongue surface (filliform) rather than removing it. Brushing without scraping had little positive effect and could actually prolong the bacterial propagation and resulting bad breath according to Dr. Dan Peterson on the Family Gentle Dental website 2.
The gag reflex is triggered because the problematic bacteria tend to gather in the rear of the mouth where brushing is most likely to make you gag. The Bad Breath Killer website reports this is temporary and tolerated by most people.
Taste Buds Damage
Damage to the taste buds and opening the way for possible infection are side effects of brushing the tongue too vigorously or with harsh bristles. The Bad Breath Killer website advises gentle brushing or scraping of the tongue to avoid damage to its surface.