Opening your mouth to speak and having everyone scurry away for safety could be quite embarrassing. Scientists know this. This is why they’ve discovered a convenient way to dispel bad breath: probiotics. According to a new study published in the journal BMJ Open, taking foods containing probiotic bacteria such as yogurt, sourdough bread, and miso soup could get rid of persistent bad breath.

More specifically, their findings reveal that bacteria such as Lactobacillus salivarius, Weissella cibaria, Lactobacillus reuteri, and Streptococcus salivarius are capable of easing bad breath and leaving the mouth fresh.

Bad breath, medically called Halitosis, is the 3rd leading cause of most patients’ referral to the dentist right after dental caries and periodontal disease.

Generally, bad breath is usually caused by volatile sulfur compounds produced by bacteria in the mouth through fermentation and decay of food particles, associated with overall poor oral hygiene.

While the accepted treatments for bad breath include scaling, tongue scrapping, antibiotics, mouthwashes, and other agents. However, they are either uncomfortable or come with a lot of side effects including dysbacteriosis and the appearance of stains on the tongue and teeth.

In a bid to combat this condition, researchers sought to discover new methods that have fewer or no side effects yet are effective in hindering halitosis. 

Although previous studies have reported probiotics as a good alternative to tackling bad breath, there is insufficient evidence for them to be clinically recommended. 

To explore the therapeutic effects of probiotics in treating mouth odor, the researchers rummaged around databases for relevant published literature up to and including February 2021.

After identifying 238 articles, the researchers then narrowed down their focus to 7 articles involving a total of 278 participants who were between the ages of 19 – 70 years. All participants were diagnosed with Halitosis. These studies compared those who underwent probiotics therapy with those who were not given probiotics and had follow-up periods varying from two to twelve weeks.

The researchers then evaluated the severity of bad breath using OLP scores and the volatile sulfur compounds concentration levels.

OLP scores showing subjective perception were generally regarded as the gold standard for diagnosing bad breath both clinically and in research. Participants were instructed to close their mouths for about a minute and then breathe out into the examiner’s nose at a distance of 10cm. Afterward, they evaluated VSC levels by instructing the participants to keep their mouths shut for 5 minutes at a stretch before measurements were taken.

In addition, the major causes of bad breath which included an unkept tongue and an accumulation of tartar on the teeth and gums were also added to the study to be analyzed. This was measured using tongue coating scores and plaque index. 

The results showed that probiotics significantly lowered the OLP scores in comparison with the placebo group regardless of the length of time of observation, thereby ascertaining the benefits of probiotics in treating bad odor.

Similarly, the results showed that those who took probiotics had a pronounced decline in VSC levels in a relatively short time, although the observed effect wore off in less than 4 weeks, after which there was no observable difference between those given probiotics and those who were not. 

However, they observed that probiotics didn’t have any significant effect on tongue coating and plaques; the main contributors to bad breath.

In the end, the team believes these biological mechanisms may be due to the interaction between probiotics and microbes in the mouth. They further explained that these probiotics work by hindering the decomposition of amino acids and proteins by anaerobic bacteria to get rid of compounds that cause odor. 

“More high-quality randomized clinical trials are required in the future to verify the results and to provide evidence for the efficacy of probiotics in the management of halitosis,” the study authors conclude in the paper.

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