Bad Breath: Causes and Treatments

Bad breath, also known as halitosis, can occur due to various causes and can usually be treated. However, for those who are unaware of effective treatment methods, it can cause mental discomfort and lead to social withdrawal. People often struggle to determine the root cause of their bad breath, leading them to rely on temporary solutions such as chewing gum or mouth deodorizing sprays, which may have undesirable side effects.

Beyond its impact on social interactions, unpleasant breath can also have medical implications. It may serve as a warning sign of an abnormal condition or even serious diseases such as lung cancer or kidney failure. Addressing bad breath not only improves one’s social experiences but can also potentially save lives. If you are struggling with bad breath, read on to learn about the most common causes, as well as methods for diagnosis and treatment.

What is Bad Breath or Halitosis?

Halitosis, also known as bad breath, is a common condition that affects many individuals. In severe cases, it may even be referred to as “bad breath cancer,” though no such cancer exists. However, halitosis can be a sign of serious health issues such as cancer, which we will discuss in detail in the section on the causes of bad breath. If you are experiencing bad breath, do not be discouraged. Roughly 1 in 5 individuals in the general population also experience this issue, and some who believe they have bad breath may not actually do so.

While some cases of bad breath may be easily preventable, others may require medical attention. It is important to understand the root causes of bad breath in order to diagnose and address the issue effectively. Although bad breath is typically not a serious concern, it may persist for more than a few weeks, indicating an underlying problem that requires attention.

What is false halitosis?

When an individual believes that their breath is unpleasant, despite objective evidence suggesting otherwise, they may be experiencing “false halitosis.” Those who suffer from halitophobia, or the fear of bad breath, may continue to experience anxiety even after a doctor has confirmed that their breath is not problematic. In such cases, speaking with a therapist or psychiatrist who specializes in treating this condition can be highly effective.

Detection of bad breath by the device and the person himself

When assessing an individual suspected of halitosis, a dentist may easily detect any unpleasant odors and utilize a six-point severity scale to evaluate the severity of the condition. Additionally, they may also scratch the back of the tongue to determine if this area is the source of the bad breath.

In order to obtain a more precise diagnosis of bad breath, various laboratory methods and tools are available. Among the most common are:

• Halimeter
• gas chromatography
• BANA test
• Beta-galactosidase test

Halimeter

This device is specifically designed to measure the levels of sulfur compounds present in the mouth and can detect even trace amounts of these compounds.

gas chromatography

This method involves the measurement of three volatile sulfur compounds, which include hydrogen sulfide, methyl mercaptan, and dimethyl sulfide. These compounds are known to contribute to unpleasant odors in the breath.

BANA test

This test measures the amount of specific enzymes produced by the bacteria that cause bad breath.

Beta-galactosidase test

Elevated levels of the beta-galactosidase enzyme have been associated with bad breath and may be one of the underlying causes of halitosis.

Symptoms of bad breath

Identifying bad breath is usually straightforward, as others may notice the problem and inform you, or distance themselves from you. The most apparent sign of halitosis is the presence of an unpleasant odor emanating from the mouth.

Other signs and symptoms of bad breath include:

• An unpleasant, sour taste or change in the taste of the mouth
• Dry mouth
• The appearance of a coating on the tongue
• Sore throat
• Tongue burning

What are the causes of bad breath?

The production of unpleasant odor in the mouth is primarily caused by the presence of bacteria that inhabit the oral cavity. These bacteria metabolize food particles, proteins, and even dead skin cells, which leads to the production and release of sulfur compounds – the main culprits behind bad breath. Practicing good oral hygiene and maintaining proper dental health is the most effective way to prevent bad breath. However, there may be instances when the unpleasant odor persists despite maintaining oral hygiene and brushing regularly, which we will explore further.

The odor of our breath can be indicative of our overall health status. The main cause of bad breath can originate from inside or outside the mouth. In over 85% of cases, bad breath is linked to oral and dental problems and diseases. The remaining 15% of cases can be attributed to other factors, which we will discuss in detail later on.

• Bad breath of oral origin
• Bad breath due to hormonal changes
• Bad breath due to consumption of food and tobacco
• Bad breath due to internal and systemic diseases

Bad breath with oral origin: The most common cause of bad breath

The reasons related to the oral cavity are:

• Teeth
• Gums
• Bacterial Plaque
• Improperly placed dental veneers
• Dentures
• Orthodontics

Teeth

Decayed teeth or improperly filled restorations can damage the gum tissue around the tooth, which can lead to food getting trapped and cause bad breath. In addition, gum disease such as periodontitis, gingivitis, and abscesses can also cause bad breath. These conditions create an environment in which bacteria can thrive, leading to the production of unpleasant odors in the mouth.

Gums

Gingivitis is a common gum disease that causes inflammation of the gum tissue, which can result in bleeding and redness. Improper brushing and not removing food from the gums can lead to gingivitis and ultimately cause bad breath.

Bacterial Plaque

Dental plaque is a soft and sticky film that forms on the teeth. It is initially yellow in color and can harden over time if not removed through regular brushing and flossing. This process of hardening is known as tartar formation, which can lead to gum disease and bad breath if not treated.

Improperly placed dental veneers

When dental crowns and veneers are not properly placed, it can lead to tooth and gum infections, which in turn can cause bad breath.

Dentures

Food particles and bacteria can accumulate between the dentures and gums, leading to bad breath. It is important to clean dentures regularly and properly to avoid this problem.

Orthodontics

Orthodontic appliances, such as braces, can make it difficult to clean the teeth and gums properly, leading to the accumulation of food particles and bacteria, which can cause bad breath. It is important to maintain good oral hygiene practices while undergoing orthodontic treatment to prevent bad breath.

Bad breath due to hormonal changes

• Bad breath during pregnancy
• Bad breath during menstruation

Bad breath during pregnancy

The hormonal changes during pregnancy can cause bad breath. Changes in the production of progesterone and estrogen in the body can lead to the formation of dental plaque. The bacteria in the plaque break down food particles, producing sulfur compounds that cause bad breath. Additionally, morning sickness during pregnancy can also contribute to bad breath.

Bad breath during menstruation

During menstruation, hormonal changes can cause an increase in sulfur-containing compounds and lead to bad breath in many women, despite an increase in saliva production.

Bad breath due to consumption of food and tobacco

As food particles break down in the mouth, the number of bacteria increases and, as a result of their activity, bad breath is created. Additionally, after consuming certain foods such as onions, garlic, vegetables, and certain spices, fragrant particles are produced that are transported to the lungs through the bloodstream, affecting the smell of a person’s breath. Consumption of substances such as coffee and alcoholic beverages can also contribute to bad breath.

To remove the smell of garlic or onion from the mouth, various solutions are available, which are discussed in an article specifically on this topic.

A diet high in sugar can contribute to halitosis as the bacteria in the mouth interact with the sugar to produce foul smells. On the other hand, consuming a diet very low in carbohydrates can lead to changes in the body’s metabolism, resulting in bad breath.

A high-protein diet can also produce and release sulfur gases during metabolism, which can cause bad breath. However, this issue can be avoided by maintaining a balanced and nutritious diet that includes vegetables and plant-based ingredients.

Tobacco products

Smoking and chewing tobacco are significant causes of bad breath. The chemicals in these substances can dry out the mouth, leading to the growth of odor-causing bacteria. Moreover, smoking and chewing tobacco can damage the gum tissue and cause gum disease, which can also contribute to bad breath. Quitting smoking and avoiding tobacco products can greatly improve oral and overall health, including reducing the risk of bad breath.

Prescription drugs

Many prescribed medications can cause dry mouth as a side effect, which provides a perfect environment for bad breath bacteria to thrive. Additionally, some medications produce chemicals when broken down in the body that can be transported to the lungs through the bloodstream, causing unpleasant breath.

Examples include certain chemotherapy drugs and sedatives such as phenothiazines. Taking high doses of vitamin supplements can also contribute to bad breath.

Bad breath due to internal and systemic diseases

Some metabolic diseases and types of cancer can cause bad breath. A study published in the journal Gut in April 2015 shows that new breath test technology can detect stomach cancer in its early stages. However, bad breath can also be an indicator of other medical conditions, including lung cancer and certain serious health issues.

• Lung Cancer
• Heart failure
• Diabetes
• Kidney failure
• Allergies and post-pharyngeal secretions
• Dry mouth
• Tonsil stone
• Intestinal obstruction
• Bronchiectasis
• Aspiration pneumonia

Lung Cancer

Can lung cancer be detected through bad breath? While pathologists typically use biopsies and ultrasound scans to diagnose lung cancer, a 2013 study suggests that breath tests could be a cheaper and non-invasive alternative. Researchers at the University of Latvia examined the breath samples of 475 subjects using a pre-programmed “electronic nose” capable of detecting volatile organic compounds (VOCs) in exhaled breath. They found that the electronic nose accurately diagnosed lung cancer in 128 non-smokers and 114 smokers, with misdiagnosis occurring in only a few cases. Other serious medical conditions may also be indicated by a person’s breath, including stomach cancer and certain metabolic diseases.

Heart failure

In a March 2013 article in the Journal of the American College of Cardiology, researchers were able to use a simple breath test to identify patients with heart failure. The study conducted by Cleveland Clinic researchers collected breath samples from 41 patients, of which 25 patients were formally diagnosed with decompensated acute heart failure. The remaining 16 patients had other cardiovascular conditions but did not show symptoms of heart failure.

Diabetes

Poorly managed diabetes can make a person more susceptible to gum disease and dry mouth, leading to bad breath. When blood sugar levels are not controlled, the body becomes weak and unable to fight the bacteria that cause gum infections, which can contribute to halitosis.

In addition, diabetic patients may experience fruity breath odor or an acetone-like odor, which can be a symptom of a serious complication called ketoacidosis. This occurs when the body does not have enough insulin to convert glucose into energy, and instead uses fatty acids, producing acidic ketones such as acetone, hydroxybutyrate, and acetoacetate. These acids are byproducts of fat metabolism and can enter the bloodstream and breath, causing a distinctive odor.

Kidney failure

Fishy breath is not always caused by eating seafood, as it may also indicate kidney failure. The kidneys are responsible for removing toxic chemicals from the blood by producing urine. In severe cases of kidney failure, the kidneys are damaged to the point that they can no longer filter toxic substances from the blood. The buildup of these substances in the body and their release into the respiratory system can cause the distinct smell of fishy breath.

Allergies and post-pharyngeal secretions

Respiratory tract infections, such as flu, bronchitis, and sinusitis, can commonly cause bad breath. Inflammation of tissue cells in the respiratory tract during these infections leads to the production of mucous secretions, and immune cells respond in that area.

Allergies and secretions from the back of the pharynx can also cause bad breath. In this condition, nasal passages become blocked, and breathing is forced through the mouth, leading to dryness and the growth of bacteria that cause bad breath.

Dry mouth

Insufficient saliva production, also known as xerostomia, can lead to dry mouth, which is a major cause of morning bad breath, particularly in individuals who sleep with their mouths open. Saliva also plays a critical role in keeping the mouth clean by washing away food particles.

Tonsil stone

The foul odor in the mouth can be caused by tonsil infections and tonsil stones. These cases can be treated by following a set of instructions or may require tonsillectomy in severe cases.

Intestinal obstruction

Intestinal obstruction and vomiting for a long time can cause a smell similar to the smell of feces in the breath.

Bronchiectasis

It is a chronic condition in which the airways become wider than normal, and the accumulation of mucus along with infection leads to bad breath.

Aspiration pneumonia

Swelling or infection in the lungs or airways that occurs due to vomit, saliva, food or liquids entering the respiratory tract and can cause bad breath.

Bad breath caused by the stomach

• Gastroesophageal reflux disease (GERD)
• Gastric cancer

Gastroesophageal reflux disease (GERD)

Digestive problems such as gastroesophageal reflux disease (GERD) can cause bad breath. When food digestion in the stomach is delayed or prevented, it can start to rot and cause bad breath, even with just a small amount of food. However, digestive health is not the only factor that can impact breath odor. A study published in 2008 in the Journal of Medical Microbiology suggests that H. pylori, a bacteria known to cause stomach ulcers, may also contribute to bad breath.

Gastric cancer

Stomach cancer screening is not common in many countries due to the invasiveness of the current method, which is endoscopy. However, a new technology called nanoarray analysis breath test has the potential to change this. This test can measure the amount of certain compounds related to stomach cancer in the breath.

In a study, researchers examined the breath of 484 people who had fasted for 12 hours and avoided smoking for at least 3 hours before the test. 99 of the participants were diagnosed with gastric cancer but had not started treatment yet.

The nanoarray analysis accurately distinguished between the early stages of gastric cancer and helped doctors identify patients who were more at risk of developing the disease. Although the study was small and preliminary, a larger trial is currently underway in Europe to determine the effectiveness of this test as a screening method.

Bad breath in the morning

It is common to experience bad breath in the morning after a good night’s sleep due to the decrease in saliva production during sleep, which can allow odor-producing bacteria to thrive. However, keeping the mouth closed for a prolonged period during sleep can also lead to reduced saliva production. This can be particularly problematic for individuals with sleep disorders like sleep apnea and snoring, who may have difficulty breathing through their nose and are forced to breathe through their mouth, leading to bad breath.

Relationship between mouth bitterness and bad breath

The most common sign of bitterness and bad taste in the mouth is the feeling of bad breath by the person and others. For some people, this problem is associated with a metallic or sour taste in the mouth. The taste that is felt in the mouth is directly related to the cause of this problem.

The reasons for bitterness and bad taste in the mouth are:

• Digestive problems and acid reflux
• Oral problems
• Sinus disease and colds
• Diseases of the tonsils and pharynx
• Neurological diseases such as epilepsy
• Taking some vitamins and medicinal supplements
• Hormonal changes such as pregnancy
• Pulmonary infections
• hepatitis B

Causes of bad breath in children

Like adults, lack of oral hygiene in children is the most important cause of bad breath. In general, the influencing factors are:

• Foreign objects
• Improper dental hygiene
• Dental infections
• Taking medicine and supplements
• Diseases

Foreign objects

Objects stuck in the nose may cause bad breath.

Improper dental hygiene

Poor dental hygiene, including inadequate brushing and infrequent flossing, is the primary cause of bad breath. Leftover food particles in the mouth provide a breeding ground for bacteria on the teeth and tongue, leading to unpleasant odors. The main culprits are bacteria in dental plaque and food residues on the tongue. Consequently, it is not surprising that most cases of halitosis are linked to inadequate oral hygiene, as well as infections and gingivitis.

Dental infections

Tooth decay, gum disease, surgical wounds, and decaying teeth are all causes of bad breath.

Taking medicine and supplements

The use of some medicines and high doses of vitamin supplements may also cause bad breath.

Diseases

Diseases such as tonsillitis, allergies and sinus infections in children can cause bad breath.

What diseases are indicated by different types of bad breath symptoms?

There exist various types of bad breath, and depending on the particular odor present in your mouth, you can identify the specific issue or disease causing it.

Fruity breath

Individuals with diabetes may have a breath that smells like ash. This is due to elevated blood sugar levels (hyperglycemia) resulting from the pancreas’s inability to produce insulin hormone or the body’s inability to use insulin effectively. When the body fails to utilize glucose for energy, it starts metabolizing fats, leading to the production of ketones. These ketones can cause a sweet odor in the breath.

Stinky breath

Syphilis, which is a sexually transmitted infection caused by the bacterium Treponema pallidum, can result in a foul-smelling breath for the patient. The disease initially manifests as a painless sore in the genital tract, intestines, or mouth. If left untreated, it can spread to the heart, brain, and other organs, potentially leading to fatality.

corpse smell

Liver failure or liver failure is a problem that can lead to death. In this disease, the liver is unable to remove bilirubin (liver waste) or filter blood or perform any of its other functions. For this reason, the smell of the mouth of a person suffering from liver failure is called “fetor hepaticus” or the smell of a dead body.

Wegener’s granulomatosis is an autoimmune disease that causes inflammation of the respiratory tract, kidneys and small vessels of the body. The breath of people suffering from this disorder can have the smell of rotting tissue or a rotting corpse.

Sour or acidic breath

Aside from oral-related issues, problems affecting the abdomen and its internal organs are the next most common causes of bad breath. Gastroesophageal reflux is a condition where the sphincter muscle at the end of the esophagus fails to close properly, leading to the backflow of stomach acid. This problem can be bothersome for patients and can result in bad breath.

Smell of fish

Trimethylaminuria, also known as fish odor syndrome or stinky fish syndrome, is a rare metabolic disease. Patients with this disorder cannot produce an enzyme called flavin monooxygenase 3 (FMO3); This enzyme breaks down compounds containing nitrogen in the diet, including trimethylamine. The result is that their breath smells like fish.

Smell of ammonia or urine

Kidney failure is a severe condition that can be fatal. Individuals with this disease have kidneys that cannot filter their blood, which normally involves absorbing water and glucose from ingested substances before excreting waste products. People with kidney failure may experience bad breath that resembles the smell of ammonia or urine.

Smell of burnt sugar

Maple syrup urine disease is a condition that is predominantly observed in infants. It is characterized by the body’s inability to process certain protein building blocks, known as amino acids, leading to a sweet-smelling urine and breath that resembles burnt sugar. If left untreated, this disease can pose a significant risk of fatality for the patient.

Sweet and sour mouth odor

Homocystinuria is a genetic disease in which the body cannot process the amino acid methionine, causing sweet and sour breath. Hemocystinuria is more common in infants and can be fatal if left untreated.

Smell of foot sweat

Isovaleric acidemia is a genetic disease in which the enzyme responsible for breaking down the amino acid leucine is not produced and leads to the accumulation of isovaleric acid in the blood. These conditions can cause the production of toxins in the body and lead to damage to the brain and nervous system. And it can also make the patient’s breath smell like foot sweat.

Smell of rotten meat

Bronchiectasis is a condition in which the airways of the lungs are dilated and lead to the accumulation of excess mucus. The resulting infection remains in the lungs and can give the patient’s mouth the smell of rotten meat.

Smell of rotting

A lung abscess—a microbial infection that can cause death (necrosis) of lung tissue and accumulation of dead tissue debris in deep cavities (more than 2 cm)—can be the cause of bad breath.

Smell of blood

Blood-related diseases or disorders, such as bleeding disorders, coagulation disorders, and red blood cell disorders, can result in a patient’s mouth having a smell similar to residual blood or a surgical wound that is just starting to heal.

Smell of rotting wounds

Liver cirrhosis is a chronic liver disease in which scar tissue develops on the liver and may eventually lead to liver failure. The breath of people suffering from this disorder can smell like rotting wounds.

Smell of ammonia

Azotemia is a biochemical abnormality in which there are too many nitrogenous substances, blood creatinine and other waste products in the body. An excess of these substances can damage the kidneys and cause the patient’s breath to smell of ammonia.

Smell of boiled cabbage

Methionine adenosyltransferase deficiency is a rare genetic disorder in which the body is unable to properly process methionine and can lead to mental retardation in some patients. Although usually, patients do not show any symptoms other than bad breath that resembles the smell of boiled cabbage.

Tips to prevent bad breath

Here are some tips to improve and eliminate bad breath:

• Brush your teeth
• Brush your tongue
• Use dental floss
• Keep your oral prostheses clean
• Prevent dry mouth
• Follow a proper diet
• No smoking

Brush your teeth

Try to brush your teeth twice a day, preferably after meals. Change your toothbrush every 2 to 3 months to prevent contamination from entering the mouth. Before going to bed, brush your teeth and rinse and gargle with alcohol-free mouthwash or salt water.

Brush your tongue

Bacteria, food, and dead cells commonly accumulate on the tongue, especially in smokers or those with dry mouth. A tongue scraper is useful for removing bacterial plaque.

Use dental floss

Brushing only cleans about 60% of the tooth surface. Dental floss removes food particles and plaque from between the teeth.

Keep your oral prostheses clean

Maintaining oral prostheses cleanliness is crucial. This includes dentures, removable partial dentures, orthodontic appliances, and other equipment that comes into contact with the mouth. Regular cleaning of these devices according to the provided instructions helps prevent the build-up and transfer of bacteria back into the mouth.

Prevent dry mouth

For individuals experiencing dry mouth, it is advisable to avoid smoking and drinking alcohol. Drinking ample amounts of water is crucial to staying hydrated. Chewing gum or sucking on candy, preferably sugar-free options, can help stimulate saliva production. If the condition persists, seeking medical assistance is recommended, and a doctor may prescribe medications to stimulate the flow of saliva. Over-the-counter moisturizers such as oral sprays, mouthwashes, or moisturizing gels can also be used to relieve dry mouth symptoms.

Follow a proper diet

Garlic, onions, and spicy foods are effective in causing unpleasant odors. Avoid eating these foods when attending gatherings. Eating too much sugary foods is also associated with bad breath. Eating a solid breakfast of bread, cereal, and vegetables can help clean the back of the tongue.

No smoking

Avoid smoking and chewing tobacco-based products.

Herbs to fight bad breath

The seven plants that we are about to introduce are not merely meant to mask bad breath. Studies have demonstrated that these plants, particularly when used together, help cleanse the oral environment and promote fresh breath.

• Peppermint
• Tee tree
• Sage
• Oregano
• Clove
• Pine needle
• Eucalyptus
• Rose Water and Vinegar Mouthwash

Peppermint

Most toothpastes contain mint flavoring for a good reason. Peppermint provides a refreshing and clean sensation in the mouth. Essential oils derived from peppermint have more benefits beyond just providing fresh breath. A research study has demonstrated that peppermint oil is more effective in combatting bad breath than laboratory-made chemical mouthwashes.

Tee tree

Tea tree oil has long been recognized by natural health practitioners for its effectiveness in combating bad breath-causing bacteria. Its unique properties have been the subject of numerous research studies investigating its potential as a mouthwash ingredient.

One study revealed that tea tree oil kills a broader range of microorganisms than the chemical compound chlorhexidine. Another study found that Solobacterium moorei, a bacteria associated with bad breath, was highly susceptible to tea tree oil. As a component of mouthwash, tea tree oil has been found to be highly effective in combating bad breath. Additionally, tea tree oil has been known to effectively treat candida, a known cause of bad breath.

Sage

Sage has been used as a herbal remedy since ancient times and modern research has confirmed its effectiveness in eliminating harmful microorganisms and fighting bad breath. Sage has been shown to effectively kill organisms that cause bad breath, such as Candida albicans, Streptococcus mutans, and Porphyromonas gingivalis. Its antimicrobial and anti-inflammatory properties make it a great natural ingredient for mouthwash or toothpaste. Sage also contains compounds that neutralize odors and leave a refreshing taste in the mouth.

Oregano

It has been utilized in various ways for centuries. It serves as an excellent natural remedy for bad breath, regardless of the cause. Oregano helps eliminate germs in the mouth and prevents conditions that may promote future growth of bacteria, thereby improving bad breath.

Clove

Cloves have been used in Chinese medicine to restore the flow of Qi, which is believed to be a cause of bad breath. Recent studies have shown that cloves are effective in eliminating bad breath and are even preferred over commercial mouthwashes in terms of taste, aftertaste, and ease of use. Cloves contain eugenol, which has antimicrobial properties and helps to fight the bacteria that cause bad breath. Herbal mouthwashes made with medicinal plants like cloves are a suitable alternative for those who cannot use chemical mouthwashes.

Pine needle

Pine needles have been used for their medicinal properties for centuries. Pine contains natural alcohols such as terpenes, which are powerful and effective cleaning agents against harmful microorganisms. Studies have shown that pine needle extract has strong antioxidant properties as well. When used as a component of mouthwash, pine needles help maintain overall oral health and eliminate bad breath-causing bacteria.

Eucalyptus

Eucalyptus has shown significant effectiveness in reducing bad breath. In a study conducted in 2010, it was found that eucalyptus plays a significant role in solving this problem by significantly reducing sulfur-containing compounds that are effective in causing bad breath. The significant effects of Eucalyptus showed that this plant, in addition to laboratory conditions, also has many cleaning effects in practice.

Rose Water and Vinegar Mouthwash

To make this mouthwash, mix 5 cups of rose water with 1 cup of vinegar. You can use it several times a day.

This mouthwash is particularly useful after tooth extraction to prevent bleeding. It deodorizes the mouth and eliminates infections and bacteria. It is also beneficial for loose teeth, mouth sores, and pimples inside the mouth.

If you experience a burning sensation in your mouth after using this mouthwash, switch to using only rose water.