What is the best way prevent and control bad breath?

Bad breath or halitosis is caused by too much bacteria or small food parts left inside the mouth, most commonly at the back of the tongue. It can be a sign of disease within the mouth or other body diseases. People with bad breath can have low self-esteem and feel embarrassed. It can affect their personal relationships and work. In this review, we looked at treatments for bad breath due to a disease within the mouth and at treatments that aim to control not just mask bad breath.

What was the research?

A systematic review of the evidence to find out the best way to control bad breath, also called halitosis, due to a disease within the mouth in adults.

Who conducted the research?

The research was conducted by a team led by Sumanth Kumbargere Nagraj from the Faculty of Dentistry, Melaka-Manipal Medical College, on behalf of Cochrane Oral Health. Prashanti Eachempati, Eswara Uma, Vijendra Pal Singh, Noorliza Mastura Ismail and Eby Varghese were also on the team.

What evidence was included in the review?

This review is up-to-date as of 8 April 2019. The review includes 44 randomised controlled trials involving 1,809 people who were 17 to 77 years old. The review compared an intervention with another intervention, a placebo or a control. It looked at eight different ways to control bad breath: mechanical cleaning (e.g. tongue cleaners and toothbrushes), chewing gums, systemic deodorising agents (e.g. mushroom extract that you eat), topical agents (e.g. gel that you apply), toothpastes, mouthrinse/mouthwash, tablets, and combination of different treatments.

What did the evidence say?

The evidence was very uncertain for mechanical tongue cleaning versus no tongue cleaning, 0.6% eucalyptus chewing gum versus placebo chewing gum, 1000 mg mushroom extract versus placebo, hinokitiol gel versus placebo gel, 0.3% triclosan toothpaste versus control toothpaste, mouthwash containing chlorhexidine and zinc acetate versus placebo mouthwash, and brushing plus cetylpyridium mouthwash versus brushing.

Harmful effects of the different interventions were not reported or were not important.

How good was the evidence?

The level of certainty we have in these findings is low to very low. This was due mainly to risk of bias and the small number of people studied in the included trials.

What are the implications for dentists and the general public?

We do not have enough evidence to say which intervention works better to control bad breath.

What should researchers look at in the future?

Further research should be undertaken to determine the most effective methods for managing halitosis by conducting well-planned randomised controlled trials (RCTs) that are clearer and more consistent.


Kumbargere Nagraj S, Eachempati P, Uma E, Singh VP, Ismail NM, Varghese E. Interventions for managing halitosis. Cochrane Database of Systematic Reviews 2016 , Issue 5 . Art. No.: CD012213. DOI: 10.1002/14651858.CD012213.