Is chronic bad breath turning you into a hermit? It’s all in your mouth — and proper hygiene can keep bad breath at bay.

Basic dental hygiene that includes brushing and flossing is important, but the crud that collects between your teeth isn’t the only source of odor. It can come from the back of your tongue, and the culprit is sulfur-compounds, by-products that occur when anaerobic bacteria (they thrive in the absence of oxygen) break down food. These bacteria play a role in digestion, and as long as your mouth has plenty of oxygen-rich saliva, they do their job without offending. If bad breath persists, see your dentist, who will do a dental exam and inquire about your general health, diet, and medications.

The cause could be gum (periodontal) disease or some other condition that needs special treatment. “Some people have fissures and grooves in the tongue where food and plaque get trapped,” says Fieldston. They can maintain it by brushing or scraping the tongue.”

Mouth breathing is another condition that may require special treatment. “Mouth breathers can wake up with horrible breath, and their gums can become inflamed,” says Fieldston. Treatment involves wearing a plastic guard containing fluoride at night, scraping the tongue before bed.

Your dentist will refer you to your doctor if the source of your bad breath is somewhere other than your mouth.