Bacteria flourish on your tongue, especially towards the back third. These bacteria break down the leftover food in your mouth, resulting in substances called volatile sulfur compounds (VSCs). These VSCs are the most common cause of bad breath. To treat this kind of bad breath you need to reduce the amount of bacteria in your mouth.
The bacteria responsible for bad breath thrive when your mouth is dry. Conventional mouthwash, which contains alcohol, dries out your mouth and may actually cause bad breath more than it helps. Instead of an alcohol-based mouthwash, look for alcohol-free varieties or products that contain “chlorine dioxide,” which attacks the VSCs at the molecular level to treat bad breath at the source instead of just covering up the smell.
One of the easiest ways to do this is by maintaining good oral hygiene—regular flossing (daily) and brushing of the teeth and tongue (at least twice per day). The tongue is a hotbed of bacterial growth, harboring millions of organisms in a bunch of tiny nooks and crannies. The most efficient way of cleaning the tongue is with a tongue scraper, a special tool made of plastic or metal that is scraped along the surface to remove the film of bacteria. The scraper should be placed as far back on the tongue as you can to remove the most bacteria as possible.