Bad breath, or halitosis, is often caused by buildup of bacteria in your mouth that gives off noxious odors that can smell like sulfur, or worse! Studies show that about 80 percent of bad breath comes from an oral source. That is, cavities, gum disease, cracked fillings, unclean dentures – even tonsils that contain trapped food particles – all of these are potential candidates for a sour breath odor.
There are other internal medical conditions that can cause your breath to push people away. These include diabetes, liver disease, respiratory tract infections and chronic bronchitis. Consult your doctor to rule out more minor concerns, such as acid reflux, postnasal drip, and other causes of xerostomia, or chronic dry mouth.