20 Most Common Causes of Bad Breath + Solutions

20 Most Common Causes of Bad Breath

Bad breath is a common and embarrassing problem among many people, especially in the morning after waking up. Fortunately for most of us, bad breath can be easily eliminated by brushing and gargling with mouthwash. Bad breath or halitosis develops at the microbial level, and it is a result of the bacteria in the mouth breaking down the food particles left on the tongue or stuck between the teeth and gums.

Bad breath can result from poor dental hygiene and the types of food you eat. Sometimes, it is your unhealthy lifestyle habits, like smoking and drinking, which causes bad breath. This article will provide you with more in-depth information about the most common causes of bad breath and what you can do to prevent it from happening.

Here are 20 of the most common causes of bad breath. Some of these causes can be avoided while others are not that easy to prevent. All of the causes listed below have their corresponding solutions. Take note of all of them so you can always maintain a fresher breath every day.

You Just Woke Up

You Just Woke Up

It is safe to say that almost every adult has experienced waking up with a bad breath. During sleep, your body is busy working to detoxify, repair, and regenerate tissues. However, the bacteria present in your mouth are wide awake while you sleep. These bacteria can continue breaking down food particles because saliva production slows down dramatically during sleep. With no saliva to clean the mouth, the bacteria are free to thrive and do their thing inside your mouth. The buildup of bacteria is also very possible when the mouth is too dry.

The Solution

This case of morning bad breath is normal and it happens to everyone, so you don’t have to worry too much. All you have to do is practice your usual oral hygiene to eliminate bad breath in the morning.

Mouth Breathing

Frequent breathing through the mouth is not recommended by dentists because it can lead to dry mouth. As discussed previously, dry mouth is the absence of saliva and results in bad breath. Without saliva, the food particles in the teeth, gums, and tongue cannot be cleaned and washed away.

One study has shown that people who spend a lot of time working out and doing intense physical exercise are more prone to cavities and bad breath. The continuous mouth breathing and low saliva production is a big factor that was considered in the development of bad breath.

The Solution

Practice conscious breathing, especially when you are doing your daily exercise routine. Try to take a deep breath that is coming directly from the diaphragm going through your nose, instead of the mouth.

Smelly Foods

Sometimes your breath can copy the smell of the food you eat. If you eat foods with lots of garlic and onions, your breath will definitely smell of garlic and onions, which can be very bad all of the time. There are other foods that can give your breath an unpleasant odor, such as brussel sprouts, cabbages, and cauliflower. These cruciferous vegetables are high in sulfur, which also produces a very bad odor.

Bad breath can also come from the digestive tract. Burping up the vegetables that are high in sulfur can cause bad breath. When you eat these foods, the sulfuric compounds enter the bloodstream and then into the lungs, where it can still be expelled even if it has been consumed for several hours already.

The Solution

After eating smelly foods, you should chew a sugar-free gum. This will stimulate the production of saliva, which can help reduce bad breath.


There are a lot of reasons why you should quit smoking right now. Bad breath is just one of the many negative effects of smoking. The smoke and nicotine increase the risk of bad breath, and it simultaneously dries out the saliva in your mouth.

The Solution

You can temporarily mask the foul odor with mint gums, but the only real solution to this problem is to quit smoking. It can be difficult for many smokers to quit, but if you continue with this habit, then having a bad breath will be the least of your worries.

Smoking as a Cause of Bad Breath


Sometimes, the medication you are taking can be the cause of your bad breath. Certain drugs such as antihistamines, muscle relaxants, antipsychotics, and diuretics can cause your mouth to dry out. When there is a low production of saliva, then the bacteria in the mouth increases, which results in bad breath.

The Solution

Since you cannot stop taking your medication, the only solution is to clean your tongue with your toothbrush. This will get rid of the bacteria in your tongue and temporarily prevent bad breath.

Medications as a Cause of Bad Breath

Sinus Infection and Cold

The mucus in your nose acts as a protective filter against foreign particles that you breathe in. However, mucus can accumulate in the back of your throat when you develop a cold or allergy. The foreign particles can now travel into the mouth and settle on the surface of the tongue. This will eventually trigger your bad breath.

The Solution

You can use a saline nasal wash to help clear the nasal passages. If the problem still persists, then it’s time to see your doctor.

Sinus Infection and Cold as a Cause of Bad Breath

Low Carb Diet

It has been observed that people who cut down on carbohydrate intake have reported an increase in the level of halitosis. A study was made comparing low-carb diet and low-fat diet, and they found out that more people in the low-carb diet reported having bad breath than the ones who had the low-fat diet.

The Solution

If you are using a low-carb diet but you want to get rid of your bad breath, then you can use sugar-free gums to help mask the odor. Drinking more water can also help prevent bad breath.


Allowing plaque to build up in your teeth and gums is dangerous because it will lead to cavities and tooth decay. Since cavities are definitely going to cause bad breath, the holes in your teeth can make it worse. Food particles can get trapped in those cavities and it can stay in there for a long period of time, which means more bad breath for you.

The Solution

For this type of problem, the only solution is a proper oral hygiene consisting of brushing, flossing, and tongue scraping. This will clean out all the food particles stuck between the teeth and inside the cavities. You can also add the mouthwash for rinsing off the bad bacteria inside the mouth.

Dental Appliances

Examples of dental appliances are braces, fixed bridges, and dentures. Even though these dental appliances have a positive purpose for your teeth, it can still cause plaque buildup if it is not maintained properly. You need a good daily cleaning regimen if you currently have one of these dental appliances. Once plaque builds up in your teeth, it will lead to bad breath and other serious dental problems.

The Solution

Clean your dental appliances every day. Food particles can easily get lodged or stuck in your braces, dentures, and other dental appliances, so don’t forget to clean them daily.

Dental Appliances as a Cause of Bad Breath

Drinking Alcohol

The smell of alcohol can easily get transferred to your breath. A study has revealed that drinking alcohol is strongly linked to increased rate of halitosis or bad breath. Even though the subjects did not eat any food for 12 hours and brushed their teeth the following morning, they still developed bad breath. Alcohol dries out the person’s mouth, which helps the bacteria to thrive. A certain odor is also triggered when the body starts to metabolize the alcohol.

The Solution

The best solution is to just drink moderately and never get drunk. Stick to a certain limit and do not go past it. You can have a glass of water in between drinks to help keep your bad breath away.

Drinking Alcohol as a Cause of Bad Breath

Heartburn or Acid Reflux

The most common cause of bad breath is the bacteria that are present in the person’s mouth. However, there are some people who develop halitosis because of their gastroesophageal reflux disease or GERD, in which the contents of the stomach go back up to the esophagus.

A study has found that people with GERD are more likely to suffer from bad breath than others who have different digestive problems. This type of disease can damage the throat, which makes the person more susceptible to having bad breath.

The Solution

Avoid foods that can induce acid reflux such as spicy foods, fruit juices, alcohol, and coffee. Instead of drinking juices or soda, you should just drink plain water because it is easier for your stomach and it can wash away the bacteria.

Heartburn or Acid Reflux as a Cause of Bad Breath

Strep Throat

Strep throat is a bacterial infection that can cause your breath and mouth to smell bad. Sinus infections are also dangerous because they can also turn into a bacterial infection that will produce a bad odor. There are some infections that are associated with a certain type of bacteria that are capable of producing a bad odor in a person’s mouth.

The Solution

You should wash away the bacteria that are lingering in your mouth. When brushing your teeth, don’t forget to scrape the surface of your tongue to eliminate the bacteria. You should also gargle with clean water to make sure your mouth is cleansed thoroughly.

Poor Digestive Health

Poor digestive health means that there are more bad bacteria in your gut than good bacteria. There are countless bacteria living in your gut right now and they can influence certain functions in your body. In order for you to have a normal digestive health, your gut should have 85% good bacteria and 15% bad bacteria. When there is an imbalance, it can lead to other serious health problems.

If your gut has a high percentage of bad bacteria, your health is compromised and it may lead to the development of bad breath. When your breath smells like a fish, it means you have problems in your kidney. A fruity smelling breath means that the person may have uncontrolled diabetes.

The Solution

You need to put more good bacteria in your gut to balance it out and improve your overall health. Once your digestive health is improved, your breath will no longer be unpleasant.

Poor Digestive Health as a Cause of Bad Breath

Weakened Immunity

When you have a weak immune system, you are prone to develop halitosis or bad breath. A compromised immune system can no longer handle the bad bacteria that are present in the mouth, which eventually results in bad breath.

The Solution

The only solution is to build up your immune system by following a nutritious and balanced diet and regular exercise. You should also improve your sleep quality and avoid unhealthy habits.

Consuming Dairy

Dairy products like milk, yogurt, and cheese are generally good for your teeth because they provide calcium and other essential nutrients for building strong bones. However, dairy has high levels of amino acids that bacteria thrives and feeds on.

The Solution

Don’t stop eating dairy foods because it is good for you. Just be sure to always brush and floss regularly to clean your teeth, gums, and tongue. Wait at least 30 minutes after eating dairy before you brush your teeth so you won’t disrupt the production of your saliva. You can also rinse your mouth with water after eating to prevent bad breath.

Dairy as a Cause of Bad Breath


Snoring can cause dry mouth because it is mostly breathing through the mouth. If snoring becomes worse, it can definitely lead to bad breath.

The Solution

You can have your partner change your position when you start snoring during sleep. However, this will only be a temporary solution. It is still better to consult your doctor about your chronic snoring.

Snoring as a Cause of Bad Breath

Infections in the Mouth

If you’ve recently undergone oral surgery and you have surgery wounds in your mouth, it can cause bad breath. Tooth removal and mouth sores that can lead to infections can also lead to bad breath.

The Solution

Your dentist can give you the best medication for any infections in your mouth after tooth extraction or oral surgery. Once the infection clears out, your bad breath will definitely vanish.


It doesn’t mean that the pregnancy itself can cause bad breath. The main cause of bad breath is nausea and morning sickness that women experience during pregnancy. Pregnant women also go through hormonal changes and craving different foods that can all contribute to having bad breath.

The Solution

It is normal to feel some morning sickness and nausea during pregnancy. Just practice proper oral hygiene to remove and prevent bad breath. Consulting your doctor regarding frequent morning sickness and nausea is also recommended.

Pregnancy as a Cause of Bad Breath


Medications that treat allergies such as the post-nasal drip can cause bad breath. Other allergy medications can lead to dry mouth, which can also result in bad breath.

The Solution

You don’t have to stop taking your allergy medications just to prevent bad breath. Just practice good oral hygiene every day to get rid of bad breath. If you experience dry mouth, drink and moisten your mouth with water.

Tonsil Stones

Your tonsil is a tissue gland that traps bacteria that are passing through the throat and helps fight infection. However, food particles, bacteria, and dead cells can get trapped in the tonsil, which creates a white lump in the back of the throat. It has no symptom but it can cause bad breath.

The Solution

You don’t need to swab or jab aimlessly in your throat just to get rid of your tonsil stones. Just gargle with an antibacterial mouthwash to loosen and wash away your tonsil stones and eliminate bad breath.

Tonsil Stones as a Cause of Bad Breath

What Can You Do to Prevent Bad Breath?

Chewing mint gums is just a temporary answer to halitosis or bad breath. Prevention is still the best remedy for this embarrassing condition. Here are several ways on how you can stop bad breath and keep it from coming back.

Good Oral Hygiene

Brushing and flossing your teeth is probably the best way to get rid of bad breath. Since one of the most common causes of bad breath are the food particles that got stuck in your teeth and gums, getting rid of them every day will definitely stop this problem. Practice brushing your teeth twice a day with fluoride toothpaste to completely remove all the food debris and plaque. Since bacteria are also present in your tongue, you should never forget to brush it too. You should floss once a day to remove food particles that are stuck between the teeth. After brushing and flossing, you can rinse your mouth with an antibacterial mouthwash. If you are wearing dentures, you should remove it before you sleep and clean it thoroughly in the morning before you put it back in your mouth.

Drink Lots of Water

Drinking water frequently can help moisten your mouth and prevent bad breath. Chewing a gum or sucking a candy can also help stop bad breath because they can stimulate the production of saliva. Choose gums or mints that contain xylitol.

Read more – Drink Water: Drinking Water At The Correct Time

Drink Water: Drinking Water At The Correct Time

Visit Your Dentist Regularly

Visiting your dentist twice a year is much recommended if you want to maintain a very healthy teeth and gums. Your dentist can perform an oral examination to detect gum disease and other dental diseases that may increase the chances of bad breath. Regular teeth cleaning are also a very effective way to remove the stubborn plaque that causes bad breath. Plus, your dentist can give you expert advice on what to do to avoid and prevent getting a bad breath.

Stop Smoking

Smoking is one of the most common causes of bad breath. Chewing tobacco products is also a very nasty habit that leads to halitosis. Ask your dentist or doctor on how you can quit smoking in order to make your breath smelling fresh again.

Monitor the Food You Eat

As mentioned in the previous paragraphs, there are some foods that can give you bad breath. Spices like garlic and onion have a nasty reputation for giving bad breath. If you think that some of the foods you eat are causing bad breath, try listing them down and show them to your dentist. You should also make a list of the medications you are currently taking. Some medicines can play a role in making your breath smell bad.

Get Rid of Bad Breath

Get Rid of Bad Breath

How Does What You Eat Affect Breath?

Digestion starts at the mouth, when you chew your food and try to break it down into smaller pieces. If you like spicy food or food with lots of garlic and onions, it can definitely affect the odor of your breath. Brushing, flossing, and mouthwash will merely cover up the bad smell temporarily, but it will not go away completely until the food has passed completely through your body.

Sometimes, it is poor oral hygiene that will cause the bad odor in your breath. Even if you don’t eat spicy foods, you will still develop bad breath if you let food particles stay in your mouth for a long period of time. The bits of food stuck in between your teeth and gums will promote bacterial growth, which then emits the foul smelling odor.

What Health Problems are Associated with Bad Breath

Do you experience bad breath every day? Persistent bad breath that doesn’t go away can be a warning sign that you may have some health problems that need immediate attention. Periodontal disease, or gum disease, is one of the health problems that are closely linked to bad breath. Gum disease is caused by the buildup of plaque between your teeth and gums. The bacteria will then cause the formation of toxins, which will irritate the gums. If the gum disease is left untreated, it will further damage your gums and your jawbone.

Dry mouth or xerostomia can also cause bad breath. When your mouth is dry, it means there is not enough saliva to moisten the mouth. Saliva can effectively neutralize the acids produced by plaque and wash away all the dead cells that have accumulated in your tongue, cheek, and gums. If the acids and dead cells are not washed away by the saliva, they can decompose and cause bad breath. Dry mouth can be caused by constant mouth breathing, salivary gland problems, or side effects of medications.

Here are the other health problems that are closely associated with bad breath:

  • Pneumonia
  • Bronchitis
  • Diabetes
  • Chronic sinus infection
  • Chronic acid reflux
  • Liver disease
  • Kidney disease
  • Poor digestive health
  • Strep throat
  • Sinus infection
  • Cold
  • Cavities
  • Weakened immunity