Dental 4 Less, What Bad Breath Could Mean.
The most likely causes of bad breath is poor oral hygiene or gum disease, but bad breath can also signal a sinus infection, especially if you can still notices the odor when you exhale through your nose.
Bad breath can also be caused by acid reflux. According to a study in the Journal of General Internal Medicine, it found a strong association between gastroesophageal reflux disease (GERD) symptoms and bad breath, or sleep apnea, because people with sleep apnea are more likely to breath through their mouths at night, which can lead to dry mouth (another cause of bad breath).