Skip to content

Oral Care

Font Size

Bad or Changed Breath - Topic Overview

When is bad breath most likely to occur?

Everybody has bad breath from time to time, especially first thing in the morning. You also may have bad breath when you are hungry, when you are dieting, or after eating foods with a strong odor, such as garlic, onions, or pastrami.

What causes bad breath?

Many things can cause bad breath. A major cause is decreased saliva. Saliva has a cleaning action that helps reduce or eliminate bad breath. When saliva decreases, bacteria can grow, causing bad breath.

Bad breath caused by a decrease in saliva may be especially noticeable:

  • In the morning. The flow of saliva almost stops during sleep. The reduced cleaning action of the saliva allows bacteria to grow, causing bad breath.
  • When you are hungry. Bad breath is more common in people who miss meals or are dieting. Chewing food increases saliva in the mouth. When you are not eating, saliva decreases and bacteria growth increases, causing bad breath.
  • When you are dehydrated. When you become dehydrated, you do not produce as much saliva. The reduced cleaning action of the saliva allows bacteria to grow, causing bad breath.
  • From diseases that affect the salivary glands, such as Sjögren's syndrome or scleroderma.
  • When you are taking certain medicines.
  • After drinking alcohol beverages.

Other causes of bad or changed breath include:

  • Eating foods with a strong odor, such as garlic, onions, or pastrami.
  • Smoking or using smokeless (spit) tobacco, such as snuff or chewing tobacco.
  • Bacteria and plaque buildup in the mouth from food caught between teeth, dentures, or dental appliances.

Mouth and throat problems that can cause mouth odor include:

  • Throat or mouth infections, such as strep throat.
  • Dental problems, such as cavities.
  • Gum disease (periodontal disease), which may cause a metallic breath odor.
  • Tonsils with deep tunnels (crypts) that trap food particles.
  • Throat or mouth cancers.

Problems in other areas of the body that can cause mouth odor include:

  • Problems with the nose, such as a sinus infection, nasal polyps, or an object in the nose.
  • Diabetes. A symptom of very high blood sugar is a strong, fruity breath odor.
  • Digestive system disorders, such as reflux (gastroesophageal reflux disease), bowel problems, or cancer.
  • Human immunodeficiency virus (HIV) infection.
  • Liver disease.
  • Lung problems, such as an infection or cancer.
    1|2
    Next Article:

    Bad or Changed Breath Topics

    How Do I Measure Up? Get the Facts Fast!

    Number of Days Per Week I Floss

    Get the latest Oral Health newsletter delivered to your inbox!


    or
    Answer:
    Never
    (0)
    Good
    (1-3)
    Better
    (4-6)
    Best
    (7)

    You are currently

    Only 18.5% of Americans never floss. You are missing out on a simple way to make a big difference in the health of your mouth. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Floss removes food trapped between the teeth and removes the film of bacteria that forms there before it turns to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Try flossing just one tooth to get started.

    You are one of 31% of Americans who don't floss daily. You are missing out on a simple way to make a big difference in the health of your mouth. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Aim for 3 more days!

    You are one of 31% of Americans who don't floss daily, but you're well on your way to making a positive impact on your teeth and gums. Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Aim for all 7 days!

    Only 50.5% of Americans floss daily, and good for you that you are one of them! Regardless of how well you brush, plaque still forms between your teeth and along your gums. Toothbrush bristles alone cannot clean effectively between these tight spaces. Flossing removes up to 80% of the film that hardens to plaque, which can cause inflamed gums (gingivitis), cavities, and tooth loss. Congratulations on your good oral health habit!

    SOURCES:

    American Dental Association, Healthy People 2010

    This tool is intended only for adults 18 and older.

    Start Over

    Step:  of 

    Today on WebMD

    close up of woman sticking out tongue
    Sores, discoloration, bumps and more.
    toothbrushes
    10 secrets to a brighter smile.
     
    Veneer smile
    Before and after.
    Woman checking her bite in mirror
    Why dental care is important.
     

    Woman dissatisfied with granola bar
    Slideshow
    woman with jaw pain
    Quiz
     
    eroded front teeth
    Slideshow
    brushing teeth
    Video
     

    Variety shades of tea
    Slideshow
    mouth and dental instruments
    Article
     
    Closeup of a happy young guy brushing his teeth
    Tool
    womans smile
    Video