What causes bad breath?

Generally speaking, bad breath refers to halitosis. Halitosis may be caused by poor oral hygiene, improper diet, indigestion, Helicobacter pylori infection, bronchitis, or other reasons. If the above conditions occur, it is recommended to seek medical treatment promptly. Specific analyses are as follows:

1. Poor Oral Hygiene

Incomplete or irregular tooth brushing, or failure to use cleaning tools such as dental floss or mouthwash, can lead to prolonged retention of food debris in the mouth. This promotes bacterial growth and the production of unpleasant odors, resulting in bad breath. It's important to improve oral hygiene habits and brush teeth regularly.

2. Improper Diet

Consuming foods with strong odors—such as garlic, onions, and leeks—can leave volatile compounds in the mouth that cause lingering bad smells. In daily life, one should avoid or reduce intake of foods known to cause halitosis.

3. Indigestion

Indigestion is mainly caused by unhealthy eating habits, eating too quickly or excessively, or consuming hard-to-digest foods. Weakened gastrointestinal function leads to prolonged food retention in the stomach, where bacteria break down food and produce foul-smelling gases. These gases may reflux through the esophagus into the mouth, causing bad breath. Symptoms may also include bloating and belching. Treatment may involve medications such as domperidone tablets, compound digestive enzyme capsules, or omeprazole enteric-coated capsules, used as directed by a physician.

4. Helicobacter pylori Infection

H. pylori infection is associated with unhygienic eating practices, contaminated tableware, or mouth-to-mouth feeding. Once colonized in the stomach, H. pylori produces urease, which breaks down urea into ammonia, hydrogen sulfide, and other malodorous substances, leading to halitosis. Additional symptoms may include stomach pain and bloating. Treatment typically involves antibiotics and protective agents such as clarithromycin capsules, amoxicillin capsules, and colloidal bismuth pectin capsules, prescribed under medical supervision.

5. Bronchitis

Air pollution, smoking, and allergic reactions are common triggers for bronchitis. Bronchitis increases respiratory secretions, which may contain bacteria. When these secretions reach the mouth, they can produce an unpleasant odor, leading to bad breath. Other symptoms may include chest pain and fever. Patients should follow medical advice and take medications such as ambroxol hydrochloride oral solution, compound licorice oral solution, or azithromycin dispersible tablets as prescribed.

Maintaining healthy lifestyle habits, eating a balanced diet, avoiding irritant foods, improving oral hygiene, and minimizing exposure to harmful environments are essential for preventing halitosis and other oral health issues.