How your diet impacts bad breath
Bad breath is no small problem, having a potentially large impact on our self-confidence and relationships with others.
If you’ve been to our Help Centre, you’ll know some common causes of bad breath (aka halitosis) already. One of those is diet. But how much impact does diet have on breath?
Let’s take a look.
In this article:
The impact of diet on your breath
Can a bad diet give me bad breath?
Yes, it’s common for our daily diet to impact the quality of our breath. In some cases, this is because we’ve eaten smelly foods and they’ve lingered in our mouths, and in other cases our regular diet can alter things like metabolism and gastrointestinal flora (i.e. gut bacteria) - resulting in a change to our breath.
If you ever experience recurring or prolonged symptoms, any aches or pains in addition to bad breath, or you’re just worried, it’s best to visit your dentist for help.
Learn more: Cleaning and prevention at the dentist
How diet impacts breath
1. Lingering smells
It’s not very exciting, but the reality is that most of the time bad breath usually just comes from our having eaten something smelly. Garlic and onions are notorious, their sulphuric compounds absorbing into the bloodstream to be expelled back out again when we exhale.
Coffee, alcohol, curry, spicy foods, fish – these can all have a temporary effect.
Learn more: Getting rid of bad breath
2. Nutritional deficiencies
Deficiencies in certain key nutrients don’t necessarily cause bad breath by themselves, rather they can cause other oral health issues which then cause halitosis.
By way of a few examples from this paper, deficiencies in B6 are connected to periodontal disease (advanced-stage gum disease), and periodontal disease can lead to bad breath (in the form of bacteria build-up and tooth decay).
A lack of iron or enough daily calories can cause salivary gland dysfunction, meaning you produce less saliva. Saliva is the body’s natural cleaning system for the mouth, and a loss of it can lead to an increased risk of disease, infection and smells.
Learn more: All about dry mouth
3. Ketosis
Ketosis is a term for when your body burns fat instead of stored carbs for energy – it’s generally the desired outcome of a low-carb or keto diet. The theory goes, switching to a keto diet can help you lose weight.
But, the ketosis process happening inside your body also produces a type of smell, so well-linked to the keto diet it’s even got a name: “Keto breath”. According to one paper, this fruity, acetone smell can increase more than five times on the keto diet.
4. Saliva production
Saliva has a big role to play in oral health and digestion. It lubricates the mouth, helps break down food and also helps the mouth stay clean.
Diet can impact saliva production not just through malnutrition, as noted above, but also through not eating at all. Eating regular meals encourages good saliva production, so skipping can decrease that, often leading to dry mouth. Dry mouth can then create other issues, like gum disease.
5. Bacteria growth and decay
Bacteria in our mouths typically feed on some foods more than others, and when they eat well, they can produce bad smells as well as contributing to tooth decay and gum disease.
High-sugar diets in particular are often associated with oral health problems. But sugar isn’t the only concern – high sodium intake is connected to tooth decay as well, and so is acid.
Learn more: How to clean your gums and keep them healthy
Common diet fads and trends, and their effects on breath
Let’s look now at some actual diet trends and see how they impact breath. Remember, if you’re worried about ongoing or severe symptoms, it’s typically better to visit the dentist than to try home remedies – that way you’ll get personalised advice, and professional intervention where necessary.
1. Keto and low-carb diets
Does keto cause bad breath?
As we mentioned above, the keto diet is designed to get the body burning fat instead of glucose, prioritising fatty foods over carby foods.
This process is called ketosis, and ketosis is linked with a fruity smell that people call “Keto breath”. The chemicals created during ketosis (called ketones), can get into your saliva, and that tends to cause the smell.
Managing your breath while on a keto diet
It’s very hard to avoid keto breath, but you can try to mask it if it’s bothering you or your loved ones. Some tips to consider:
Carry sugarless mints with you. These will help fresh your breath, without adding more sugar to your intake.
Drink plenty of water, as this can help ‘dilute’ the smell in your mouth.
Consider a small intake of complex carbs (not processed carbs). A moderated intake of complex carbohydrates may help you minimise the symptoms of Keto breath while still maintaining your diet.
2. Paleo
Does the paleo diet cause bad breath?
The paleo diet prioritises a more natural form of food, like fruits and veg, nuts, eggs and lean meats. For some people, the objective of paleo is to activate ketosis, which can generate a “fruity” breath. For more on this, read the keto section above.
Being quite high in protein, the paleo diet can also contribute to the production of sulphuric compounds in the mouth – those occur when bacteria breaks down protein. Cue the risk of smelly breath.
Managing your breath while on a paleo diet
Maintaining good oral health practices and drinking plenty of water will generally help with the risk of smelly breath due to broken-down protein.
If ketosis is your objective with paleo, you may also wish to consider carrying sugar-free mints around too.
3. Fasting
Does fasting cause bad breath?
Fasting can cause bad breath in some cases where it reduces saliva production and activates ketosis.
With reduced saliva production, you’re at a higher risk of dry mouth. This, in turn, increases your risk of oral health issues, as well as smelly foods and compounds lingering in the mouth for a longer period of time.
As for ketosis, you can read more about that in the Keto section above.
Managing bad breath while fasting
Even if you’re fasting, it’s still important to maintain good oral health practices. That means brushing and flossing regularly, keeping bacteria down in your mouth.
To fight dry mouth, drink water more regularly and avoid things which can dry the mouth out – caffeine and alcohol, for instance, or alcohol-containing mouthwash.
If you can’t drink water during your fast, then it’s all the more important to brush your teeth properly and rinse your mouth outside of fasting hours. You might also consider a trip to a dental hygienist prior to the fasting period to ensure your mouth is in good condition.
4. Juicing and liquid diets
Can liquid diets cause bad breath?
Liquid diets may cause bad breath in two ways: activating ketosis due to low carb consumption, and discouraging saliva production.
Saliva production typically comes from chewing, so while you might be fairly well hydrated on a liquid diet, the lack of chewing may limit the amount of saliva you produce.
As for ketosis, we’ve covered that in the Keto section above!
Managing bad breath on a liquid diet
To fight bacteria build-up, you’ll need to maintain good oral health habits. That means brushing and flossing regularly, and it’s also a good idea to rinse your mouth with water after you consume anything acidic or sugary (such as fruit).
As for “Keto breath”, if it’s a problem for you then consider carrying some sugar-free mints around to mask the smell.
5. Vegan
Can a vegan diet cause bad breath?
There is a connection between vegan (and vegetarian) diets and halitosis, or bad breath, as noted in this paper – though the link isn’t strong. Certain nutritional deficiencies and consumption of odour-causing foods may cause halitosis in the vegan context.
Deficiencies in nutrients like B12 or protein can lead to bad breath, and this is a relatively common issue among vegan dieters.
Plus, certain vegetables have been known to cause temporary bad breath as they break down in the mouth (such as cabbage or broccoli).
Managing bad breath on a vegan diet
The first stop to managing halitosis on a vegan diet is to review what you eat to ensure you’re getting all the nutrients the human body needs on a regular basis. Some common nutrients just aren’t found all that strongly in plant-based foods, meaning alternatives must be sought.
Note: It is always recommended that you visit a medical professional such as your GP or a qualified dietician before making big changes to your diet.
If you’re worried about bad breath after eating smelly foods (or foods which smell when being broken down), consider rinsing your mouth with water after eating to wash out whatever’s in there. Sugar-free mints may also help.
Of course, to fight bacteria build-up, one of the best defences is always good oral health practices - brushing and flossing twice daily, for example.
Strategies to stop bad breath while dieting
For those who’ve been following along with this blog, you’ll already have some good go-to strategies for managing your breath while on specific diets.
Here, we’ll go over some of those again and expand with more detail.
1. Hydration
In many cases, the cause of bad breath while dieting is a lack of saliva production. Saliva lubricates the mouth and helps clean it out after eating, so drying out can be a precursor to bad breath (among other oral health issues).
Drinking plenty of water, therefore, has a couple of benefits:
It helps your body produce saliva.
It rinses your mouth, helping remove trapped food, sticky acids, and odour-causing compounds, while diluting odorous saliva.
2. Oral health
Bad breath is often a result of bacterial build-up in our mouths. When bacteria feed on food particles and sugars in the mouth, they can produce bad smells (called volatile sulphur compounds).
Additionally, bacteria contribute to tooth decay and gum disease – both of which can further produce bad smells (not to mention the damage to your teeth and gums themselves!).
Maintaining good oral health disrupts the production of bacteria and can help disinfect your mouth. That means:
Brushing twice a day with a fluoride-containing toothpaste, including the fronts, backs and chewing surfaces of your teeth, plus the gumline and your tongue.
Flossing regularly, for example once a day.
Rinsing your mouth with water after eating, especially if you’ve had anything sugary, carby or acidic.
3. Breath-improving foods
Some foods are known to help improve the freshness of your breath, and consuming these could help you manage the effects of halitosis as a result of any diet you’re on.
For example, crunchy, fibrous fruit and veg (think apples, carrots and celery) help to dislodge stuck food particles and stimulate saliva production - essentially, helping to clean the mouth naturally.
Yoghurt may also help. Researchers from Tsurumi University found that eating sugar-free, traditional yoghurt can help reduce levels of smelly compounds in the mouth. Ginger may also help by doing the same thing.
4. Breath masking
Finally, there’s breath masking. Breath masking doesn’t tackle the root cause of bad breath, it just covers the symptoms (i.e. the bad smell). That means it isn’t something you can do long-term to get rid of halitosis, but you can use it to solve short-term problems where your breath is an issue for you.
Some quick breath-masking tips include:
Carry sugar-free mints or chewing gum for a quick burst of minty freshness. Chewing or sucking can also stimulate saliva production. Emphasis on sugar-free!
Brush your teeth with minty toothpaste before a situation where you’re worried breath will be a problem.
Drink a glass of water after eating, to rinse your mouth.
5. Regular dental check-ups
Bad breath is often associated with oral health issues. Even if you aren’t experiencing other symptoms (such as pain or bleeding), chronic bad breath may be a precursor to something else.
Visiting your dentist at least once annually, or twice if you are at a higher risk, will ensure a professional can examine your mouth, talk to you about your daily habits, and recommend treatment options if there’s a brewing problem.
Who’s at higher risk? Common risk factors include:
Diet-related bad breath FAQ
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Yes, intermittent fasting can affect bad breath.
Fasting can decrease saliva production in the mouth and kickstart a process called ketosis, which is the burning of fat in the body. Both of these may negatively impact breath.
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A balanced, healthy diet is generally always best for any health concerns, unless you have specific intolerances preventing you from eating certain foods. That said, there is no one diet that is a miracle cure for bad breath.
Still, there are good foods and bad foods when it comes to bad breath. Such as:
Fibrous fruits and veg can help clean the mouth and dislodge stuck odour-causing food particles, like natural toothbrushes. Certain foods like natural yoghurt and ginger may fight odours too.
As nutrient deficiency is one potential cause for bad breath, a balanced diet rich in nutritional value can help prevent this issue.
Low-carb diets can lead to ketosis, which can cause “Keto breath”.
Things to avoid for bad breath tend to be sugars and processed grains, strong-smelling food (like onion or garlic), and anything which dehydrates you – such as caffeine or alcohol.
If you have specific dietary needs or questions, it’s best to consult your GP before making any major changes.
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Certain weight-loss diets low in carbohydrates can cause a process known as ketosis, which is the burning of fat in the body. This process produces chemicals called ketones, which have an unusual “fruity” smell that can linger in the saliva.
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In order to smell your own breath to identify if you have “Keto breath”, you can lick the back of your wrist and sniff that. People typically describe this smell as being fruity, or like ammonia or acetone.
Generally, humans can’t smell their own breath otherwise – cupping your hand and breathing into it rarely works.
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Being overweight does not generally cause bad breath on its own, however certain dietary choices and other factors associated with weight may cause bad breath.
One study found a connection between obesity and halitosis. The researchers surmised that this link was due to obese people possibly having a diet which promotes dry mouth (which can cause bad breath).
Problems like sleep apnoea or insulin resistance (i.e. diabetes) are also connected to oral health issues.
If you’re concerned about your oral health, consult your dentist. Or, if you're worried about your weight, consult your GP.
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A low-carb diet can lead to bad breath, if your intake of carbs drops to the point that your body enters ‘ketosis’ – the burning of fat instead of glucose (sugars from carbs.
Ketosis has been known to cause a fruity breath, which some people describe as smelling like acetone or nail polish remover.
Need advice about your oral health? Talk to us today
Don’t sit on your symptoms. If you’re worried at all about your breath, the condition of your teeth or any other oral health issues, it’s generally best to see a professional.
We’re located on Maunu Road in Whangārei, and you can book an appointment either online or by calling us on 09 430 0707.