The foul oral odor is usually caused by a group of anaerobic, sulfur-producing bacteria that breed beneath the surface of the tongue and often in the throat and tonsil area.

The term “anaerobic” literally means living without oxygen, and in fact, these bacteria do not require oxygen to live.

They occur naturally in the oral environment and are essential because they assist in digestion by breaking down proteins into amino acids. Proteins are commonly found in food, mucus or phlegm, blood, and in diseased oral tissue.

As these bacteria feast on proteins in your mouth, sulfur compounds are released from the back of your tongue and throat.

The bacteria excrete waste as hydrogen sulfide, methyl mercaptan, and other odorous and bad tasting compounds known as volatile sulfur compounds. As long as the anaerobic bacteria feed on proteins and excrete volatile sulfur compounds unchecked, your breath will become worse and worse.
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