Halitosis is the medical term for persistent bad breath. The reasons behind it vary, ranging from issues with gums and teeth to problems within internal organs, according to an otolaryngologist from SM-Clinic, Dr. Erzhena Dymchikova, speaking with socialbites.ca.
The most frequent culprit is dental disease. Conditions such as gingivitis, tooth decay, periodontitis and related gum problems often drive unpleasant odors that emanate from the mouth. Poor dental hygiene, lingering plaque, and untreated cavities can all contribute to the persistent smell, creating a cycle that worsens if not addressed by dental care.
The next common source involves the nose, throat, and tonsils. Inflammation or infection in these areas, including tonsillitis, sinusitis, a deviated nasal septum, and rhinitis, can produce odors that are difficult to eliminate. Microorganisms thrive in the tonsillar areas, and their metabolic activity can generate foul-smelling byproducts. This is why problems in the upper airway frequently present as halitosis even when the mouth itself seems clean.
When sinus and nasal conditions are present, two mechanisms contribute to bad breath. One is the drainage of nasal secretions toward the back of the throat and into the pharynx, where it can mingle with saliva and linger near the tongue base. The other factor is mouth breathing caused by nasal congestion. Breathing through the mouth dries the oral surfaces, reducing saliva’s cleansing effect and allowing bacteria to multiply more readily, which intensifies the odor.
Dr. Dymchikova emphasizes that anyone experiencing noticeable bad breath should first seek evaluation from a dental professional and then consult an otolaryngologist if needed. A comprehensive check helps determine whether the smell originates in the mouth or from the upper airway, guiding appropriate treatment choices.
Beyond the mouth and upper airways, halitosis can also reflect conditions within internal organs. Issues affecting the gastrointestinal tract — such as gastritis, structural changes like an esophageal diverticulum, or gastroesophageal reflux disease — can contribute to odors that reach the mouth. Respiratory conditions including bronchitis, bronchiectasis, pneumonia, pulmonary abscess, or even early cancer can be associated with halitosis. Liver and kidney diseases, as well as certain endocrine disorders, may also influence breath quality by altering the body’s metabolic balance.
Understanding the full spectrum of potential causes is essential for an accurate diagnosis. While many cases originate in the mouth, a thorough medical history and targeted examinations help distinguish dental problems from nasal, throat, digestive, or systemic conditions. Lifestyle factors, such as tobacco use, certain foods, and inadequate hydration, can worsen symptoms and should be reviewed during clinical assessment. Diagnostic efforts often combine dental examination, nasal endoscopy, and, when indicated, imaging studies or laboratory tests to map out the source of halitosis and plan effective treatment. [Source: SM-Clinic clinical guidance]n