According to the results of a study published in, Journal of Agricultural and Food Chemistry, magnolia bark extract contains chemicals that may prevent bad breath or halitosis. These compounds, called magnolol and honokiol, kill the bacteria that cause bad breath and cavities.
In this study, nine healthy adults took a breath test one hour before having lunch. As a first step in the study the participants provided saliva sample. Then they were asked to chew on breath mints, some of which contained magnolia extracts. Participants were asked to give the saliva sample for 30 minutes.
The results showed that those who got magnolia bark extract in the breath mints had 61% reduction in the bacteria that causes bad breath during the breath analysis 30 minutes after having the gum mint. The drop in bacteria was just 4% in those who had gum mints without magnolia.