Breath Odor
Bad breath can come from the mouth, teeth, or as a result of an underlying health problem. Common causes include poor dental hygiene, smoking, ...

Table of Contents
powered by healthline

Average Ratings

What Is Breath Odor?

Breath odor problems affect everyone at some point in their lives. Odor can come from the mouth, teeth, or as a result of an underlying health problem. Bad breath odor can be a temporary problem or a chronic condition. According to the Academy of General Dentistry, more than 80 million people suffer from chronic halitosis, or bad breath (AGD, 2012).

What Are the Causes of Breath Odor?

Poor Dental Hygiene

Bacteria breaks down food particles trapped in the teeth or mouth. The combination of the bacteria and decaying food in your mouth produces an unpleasant odor. Brushing and flossing regularly removes trapped food before it decays.

Brushing also removes plaque, a sticky substance that builds up on your teeth and causes odor. Plaque buildup can cause cavities and periodontal disease. Bad breath also can be a problem if you wear dentures and do not clean them every night.

Strong Foods and Beverages

When you eat onions, garlic, or other foods with strong odors, oils from the foods are absorbed into your stomach during digestion. These oils pass into your bloodstream, travel to your lungs, and are noticeable in your breath for up to 72 hours. Drinking beverages with strong odors, such as coffee, can contribute to bad breath.


Smoking cigarettes or cigars causes a bad odor and dries out your mouth, which can make odor even worse.

Dry Mouth

Dry mouth can occur if you do not make enough saliva. Saliva helps keep your mouth clean and reduces odor. Dry mouth can be a problem if you have a salivary gland condition, sleep with your mouth open, or take certain medications, including those that treat high blood pressure and urinary conditions.

Periodontal Disease

Periodontal disease happens when plaque is not removed promptly from teeth. Over time, plaque hardens into tartar. Tartar cannot be removed by brushing and can irritate your gums. Tartar may cause pockets, or small openings, to form in the area between the teeth and gums. Food, bacteria, and dental plaque can collect in the pockets, causing a strong odor.

Sinus, Mouth, or Throat Conditions

Bad breath odor may develop if you have a sinus infection, postnasal drip, chronic bronchitis, or an infection in your upper or lower respiratory system. Tonsil stones also can be a source of bad breath because bacteria tend to collect on the stones.


Unusual breath odor can be a symptom of some diseases, including kidney disease, diabetes, and gastroesophageal reflex disorder (GERD). If you have kidney or liver failure or diabetes, your breath may smell fishy. When your diabetes is not under control, your breath may smell fruity.

What Are the Symptoms of Breath Odor?

In addition to a bad smell in your mouth, you may also notice a bad taste in your mouth. If the taste is due to an underlying condition and is not because of trapped food particles, it may not disappear even if you brush your teeth and use mouthwash.

How Is Breath Odor Diagnosed?

Your dentist will smell your breath and ask you questions about your problem. He or she may recommend you schedule an appointment for the morning, before you brush your teeth. You can expect to answer questions regarding:

  • how often you brush and floss
  • the kinds of food you eat
  • allergies or diseases
  • how often you snore
  • medications you take
  • when the problem started.

Your doctor will smell your mouth, nose, and tongue to diagnose your problem and will try to determine the source of the odor. If the odor does not seem to be coming from your teeth or mouth, your dentist will recommend that you visit your family doctor to rule out an underlying disease or condition.

How Is Breath Odor Treated?

If breath odor is caused by a plaque buildup, a dental cleaning may solve the problem. A deep dental cleaning may be needed if you have periodontal disease. Treating underlying medical problems, such as a sinus infection or kidney disease, can also help improve breath odor. Your dentist may recommend that you use an artificial saliva product and drink plenty of water if dry mouth causes your odor problem.

How Can I Prevent Breath Odor?

  • Brush your teeth two or more times each day.
  • Floss daily.
  • Use antimicrobial mouthwash to kill bacteria.
  • Brush your tongue to remove bacteria.
  • Drink water to wash away food particles and keep your mouth moist.
  • Quit smoking.
  • Clean dentures, mouth guards, and retainers daily.
  • Replace your old toothbrush with a new one every three months.
  • Schedule a dental cleaning and examination every six months.
Written by: Holly McGurgan
Edited by:
Medically Reviewed by: George Krucik, MD
Published: Jul 16, 2012
Published By: Healthline Networks, Inc.
Top of page
General Drug Tools
General Drug Tools view all tools
Tools for
Healthy Living
Tools for Healthy Living view all tools
Search Tools
Search Tools view all tools
Insurance Plan Tools
Insurance Plan Tools view all tools