Vanquishing ‘dragon breath’ and bacteria is simple quest

Dear Doctor K: My breath is OK during the day, but when I wake up in the morning, it’s terrible. What causes bad morning breath? And what can I do to prevent it?

Answer: Bad breath, or halitosis, is a common problem — especially “morning breath.” (Some people call it “dragon breath.”)

Certain foods can cause bad breath. Garlic and onions are classic examples. Reflux of stomach contents can do the same. So can serious diseases of the liver or kidneys. Infections of the tonsils, sinuses or respiratory tract can also be responsible for bad breath.

But the most common cause of bad breath in the morning are bacteria that reside in your mouth. Like us, bacteria need food to live. They get their food from substances that cover our gums, tongue and throat, and that fill the spaces between our teeth. When bacteria “digest” their food, they make various bad-smelling gases, including sulfides and amines.

These bad- smelling gases are most likely to be produced at night. That’s because during the night most of us do a lot of breathing through our mouth. That causes saliva to dry out, and the dry environment encourages the bacteria to produce more gases. Any medication or condition that reduces the flow of saliva can do the same. Morning breath is unpleasant, but it can be quickly relieved by rinsing your mouth with water or mouthwash.

Halitosis that lasts throughout the day is also triggered by the wide range of bacteria that live in everyone’s mouth. When you don’t brush your teeth twice daily, there is more “food” around for the bacteria in your mouth.

Poor oral hygiene also increases the amount of dental plaque, and bacteria love to live in the plaque. Diseases of your gums and structures supporting the teeth can allow these bacteria to get the upper hand and cause halitosis. Even when teeth and gums are healthy, dentists suspect that bacteria on the tongue contribute to bad breath.

If you have bad breath, here’s what to do:

Keep the saliva flowing. Drink plenty of water and chew sugarless gum.

Avoid antihistamines and other medications that dry the mouth, if alterna- tive medicines work just as well.

See your dentist regularly and get prompt treatment for any problems.

Get your teeth cleaned by a dental hygienist at least twice a year.

Practice meticulous oral hygiene. That means f lossing regularly and brushing your teeth — and tongue — diligently.

That’s right, the tongue. Brushing the upper surface of your tongue every time you brush your teeth removes a lot of gas-producing bacteria.

Avoid foods (like onions and garlic) that you find make your breath smell bad.

Don’t smoke or chew tobacco. They encourage the growth of mouth bacteria and irritate the nose and sinuses, making them more vulnerable to infection.

Use an antibacterial mouthwash.

Keep breath mints on hand for a quick, if temporary, cover-up.

Finally, relax. It’s simple to reduce bad breath in the morning. Dr. Komaroff is a physician and professor at Harvard Medical School. To send questions, go to AskDoctorK. com, or write: Ask Doctor K, 10 Shattuck St., Second Floor, Boston, MA 02115.