What are the causes of halitosis (bad breath)?

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From the Guidelines

Halitosis can be effectively managed through proper oral hygiene and addressing underlying causes, with a focus on natural products and good oral health practices, as supported by recent studies 1. To manage halitosis, it is essential to practice good oral hygiene, including brushing teeth twice daily with fluoride toothpaste, flossing daily to remove food particles between teeth, and cleaning the tongue with a tongue scraper or toothbrush to remove bacteria. Rinsing with an antimicrobial mouthwash containing chlorhexidine (0.12%) or cetylpyridinium chloride once or twice daily can also help. Staying hydrated by drinking plenty of water throughout the day is crucial, as dry mouth contributes to bad breath. If dentures are worn, they should be cleaned thoroughly every night. Avoiding tobacco products and limiting foods with strong odors like garlic and onions can also help reduce halitosis. Some key points to consider in managing halitosis include:

  • Brushing and flossing regularly to remove bacteria and food particles
  • Using an antimicrobial mouthwash to reduce bacteria in the mouth
  • Staying hydrated to prevent dry mouth
  • Avoiding tobacco products and strong-smelling foods
  • Considering over-the-counter products containing zinc compounds or chlorine dioxide for persistent halitosis
  • Consulting a dentist or physician if bad breath persists, as it may indicate underlying conditions like gum disease, sinus infections, or gastrointestinal issues. It is also important to note that while tonsillectomy may be considered for certain conditions, such as sleep-disordered breathing, its benefits for halitosis must be weighed against the risks of surgery, as stated in the guidelines 1. However, the most recent and highest quality study 1 suggests that natural products and good oral health practices can be effective in managing halitosis.

From the Research

Causes of Halitosis

  • Halitosis is caused primarily by bacterial putrefaction and the generation of volatile sulfur compounds 2
  • Ninety percent of patients suffering from halitosis have oral causes, such as poor oral hygiene, periodontal disease, tongue coat, food impaction, unclean dentures, faulty restorations, oral carcinomas, and throat infections 2
  • The remaining 10 percent of halitosis sufferers have systemic causes that include renal or hepatic failure, carcinomas, diabetes or trimethylaminuria 2
  • Halitosis can be caused by oral disease or by respiratory tract conditions such as sinusitis, tonsillitis, and bronchiectasis 3
  • An estimated 40% of affected individuals have no underlying organic disease 3

Prevalence of Halitosis

  • Studies worldwide indicate a high prevalence of moderate halitosis, whereas severe cases are restricted to around 5% of the populations 4
  • Halitosis has multiple sources and negative impacts on people's social interactions and quality of life 5

Diagnosis and Treatment of Halitosis

  • Modern analytical and microbiological techniques permit diagnosis of bad breath 2
  • Management of halitosis involves maintaining proper oral hygiene, and periodontal treatment, including tongue brushing 2
  • Effective interventions should be tailored based on the specific etiologies and mechanisms involved 6
  • Enhancing oral hygiene habits, using antimicrobial drugs, or administering probiotics may help regulate oral or intestinal flora, thereby improving halitosis and overall oral health 6
  • Interventions such as artificial saliva, cleaning, brushing, or scraping the tongue, regular use of mouthwash, sugar-free chewing gums, and zinc toothpastes may be effective in treating halitosis 3

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Halitosis. A common oral problem.

The New York state dental journal, 1996

Research

Halitosis.

BMJ clinical evidence, 2014

Research

Halitosis: etiology, prevention, and the role of microbiota.

Clinical oral investigations, 2023

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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