Halitosis is caused by the bacteria that live on and around your teeth, gums and tongue. Breath mints and mouthwashes do not cure bad breath, they only mask the symptoms. Proper oral hygiene can cure many cases of bad breath. However, in some cases, bad breath is caused by more serious conditions. Sinus and tonsil infections, acid reflux, ulcers, diabetes, hypoglycemia, kidney malfunction, and eating disorders are just some of the health issues that can cause bad breath.