We all experience moments of smelly breath. However, for others it can be a chronic problem. The medical term for this type of bad breath is ‘halitosis’. A build-up of bacteria in the mouth can be a common cause, however there can be many reasons for this build-up of bacteria. Below are just some of the common causes of bad breath and what you can do about them.


After smoking a cigarette, your breath is likely to smell of cigarette smoke – which for some people can be unpleasant. However, this is not the only way in which smoking can make your breath smell. Smoking dries out the mouth, causing bacteria to build up. It’s also a leading cause of gum disease, creating further odor.

If you’ve been told your breath smells and you smoke, an obvious solution is to give up smoking. Unfortunately, vaping isn’t great for your breath either, however it does eliminate the smell of smoke making it a better alternative. Don’t rely on chewing gum or menthol cigarettes to try and cover up the smell. 


If you’ve ever experienced someone else’s ‘coffee breath’, you’ll know it’s not pretty. This odor is caused by drinking lots of coffee. This not only makes your breath smell of coffee, but dries it out, causing bacteria to thrive, which then adds to the odor. 

While you can chew a mint to get rid of coffee breath, there are other solutions. Following up your coffee with a glass of water could help to hydrate your mouth and wash away coffee residue. Certain foods like apples, oranges and yoghurt also have odor neutralizing properties. 


People who drink a lot of alcohol can often end up with bad breath. Not only do many alcoholic drinks carry a pungent smell, but they also dry out the mouth, allowing bacteria to build up. Alcoholic drinks can also cause acid reflux, causing stomach acids to end up in the throat, further causing a pong.

If you’re a heavy drinker, the best solution is to drink less alcohol. After a heavy night drinking, always brush your teeth thoroughly and try to drink lots of water to help prevent your mouth from drying out.  

Dry mouth

Some people naturally suffer from a dry mouth – also known as xerostomia – which is caused by salivary glands failing to produce enough saliva. This can make your mouth more susceptible to build-ups of bacteria (your saliva helps to clean your mouth) which can then lead to bad breath.

If you think that you may suffer from this condition, it could be worth seeing a doctor. There are various forms of medication that can be prescribed including saliva stimulants such as Salagen and Evoxacm, as well as mouth rinses and moisturizers. 

It’s worth noting that dry mouth may not always be a medical condition, but an effect of something else. As mentioned already, smoking, alcohol and coffee can all lead to dry mouth. There are also other possible causes including taking certain medication, not drinking enough water, sleeping with your mouth open (especially in a heavily air conditioned room), eating too many salty foods or regularly suffering from anxiety.

Poor oral hygiene

Poor oral hygiene can also lead to bad breath. If you’re not brushing your teeth thoroughly and regularly, you can expect bacteria and plaque to build up, which is likely to give your breath a foul odor. 

We should all be brushing out teeth twice per day for two minutes at a time. Try to brush each tooth individually in a circular motion (electric toothbrushes automatically do this) in order to have the best impact. Rinsing your mouth out with non-alcoholic mouthwash can further help to kill bacteria and keep breath smelling fresh. It’s also worth flossing to get rid of plaque between teeth. 

Tooth decay

If you have tooth decay, this could also be contributing to bad breath. Tooth decay occurs when bacteria produces acids which begin to erode the enamel on our teeth. These cavities allow bacteria to get into the teeth where they cannot be as easily cleaned away, causing smelly build-ups of bacteria within the mouth.

If you’re experiencing tooth decay, it’s worth seeing a dentist who may be able to offer treatment. This could include fluoride treatment, a filling or another form of treatment. Getting rid of the bacteria causing the decay will help to preserve your teeth and make your breath smell fresher.

Gum disease

On top of tooth decay, it’s worth looking out for gum disease. This is when plaque starts to irritate gums, often leading to bleeding and inflammation. In serious cases, the gums and jaw can become infected, leading to periodontitis, which can cause chronic bad breath and receding gums. 

To help treat periodontitis, it’s worth seeing a specialist called a periodontist. There may be treatments that can be carried out to reduce infection of the gums. 


Undiagnosed diabetics can sometimes experience a problem called ‘acetone breath’. This is when breath starts to take on the fruity scent of nail polish remover. This is a result of too many ketones being released into the blood to make up for the body’s inability to convert blood sugar into energy (as a result of an insulin deficiency). 

This is typically a symptom of type-1 diabetes and may be accompanied by other symptoms such as dry mouth, frequent urination, tiredness and dizziness. It’s worth seeing a doctor to get an official diagnosis for diabetes. Type-1 diabetes can be treated by taking insulin. 

Kidney and liver disease

In rare cases, bad breath can be the result of kidney or liver disease. In such cases, breath may smell like ammonia or sulfur. This is due to the kidney or liver failing to filter out toxins properly causing them to enter the bloodstream and saliva. 

Liver and kidney disease will usually be accompanied by other symptoms such as tiredness, weight loss, swollen ankles or skin tone changes. You should see a doctor immediately if you experience these symptoms and haven’t already been diagnosed.