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What Causes Bad Breath and How to Fix It

By August 2, 2021May 26th, 2022Blog
what causes bad breath

Even at our most confident, we can feel self-conscious about our breath at times. A job interview? A first date? Or just meeting up with friends? Bad breath can be… awkward, maybe even embarrassing. In any case, having bad breath can put a damper on day-to-day life. 

If bad breath is a worry for you, Dr. Buddy Davis, Dr. Adam Hardin, and Dr. Sarah McKee want to help you figure out the cause and give you some tips on how to get rid of it. After all, bad breath can sometimes be directly related to your oral health. And when it comes to your mouth, Davis Orthodontics is all about helping you achieve a straight and healthy smile you’re proud of!

What is Bad Breath?

First off, let’s start by saying that if you have bad breath, you’re not alone! Bad breath, or “halitosis,” is a common problem. In fact, 1 in 4 people report it as a persistent issue, with up to 50% of people saying they’ve had it at one time or other. And we think those are the ones honest enough to admit it!

Bad breath happens in several ways. Sometimes it comes from what you’ve just eaten, like garlick-y or onion-y foods. Other times, bad breath is due to lifestyle habits or certain diet restrictions. Chronic bad breath can also be a sign of oral health or medical issues.

What Causes Bad Breath?

Here, your Upstate SC orthodontist has compiled the most common causes for bad breath. Some on this list will ring a bell, though other reasons for bad breath might just surprise you!

Foods and Drinks:

Flavorful Foods – As much as foods like garlic and onions add a lot of flavor to your favorite dishes, it’s no surprise that they contribute to bad breath, both right after you’ve eaten and often for the next few days. So what causes bad breath from pungent foods? These food particles enter the bloodstream, are carried to your lungs, and then come out every time you exhale.

And since food takes three days to completely digest and leave your body, that’s three days that odorous food can affect your breath. In addition to garlic and onion, you’ll find that spicy foods, curries, and horseradish can also linger on your breath.

Citrus Foods – Bacteria loves an acidic environment. We’re talking about the unhealthy bacteria that can lead to plaque build up in your mouth if you don’t brush or rinse it away. So even though citrus foods taste great and are packed with vitamin C and other nutrients, their acidity can raise the level of bad bacteria in your mouth. Bad bacteria = bad breath. 

Eating Too Much MeatEating a steak isn’t going to automatically give you halitosis. But excessive protein consumption — like in a high-protein diet — can contribute to bad breath. When you digest protein, your body produces ammonia, resulting in an unpleasant smell when you breathe out. To counteract this, we suggest eating plenty of foods that contain zinc (hello spinach, pumpkin seeds or chickpeas!).

Canned Fish – Why only canned fish and not fresh fish, too? Canned fish, like salmon and tuna, has had time to oxidize and react to other elements, resulting in a compound called trimethylamines. This chemical reaction results in that “fishy smell” that most people find a bit unappealing. Unless you eat something acidic with your tuna sandwich or chew some sugarless gum right after, that distinct canned fish smell can stay on your breath for a while.

DairyMilk and milk products definitely have their oral health benefits — think calcium and vitamin D for strong teeth and jawbones. But dairy can also cause your breath to smell. Yes, when you drink milk or eat cheese, the natural bacteria in your mouth reacts with the amino acids in dairy. The outcome: a not-so-pleasant odor. Some describe it as a sulphur-like smell, aka, rotten eggs!

Peanut Butter Yes, peanut butter can cause bad breath. Just like meat, it’s potential for causing an unfriendly odor in your mouth is related to the fact that it’s a protein. Even though it’s healthy, peanut butter can cause bad breath in two ways: one, its pasty consistency makes it hard for saliva to break down the proteins once they’re in your mouth; and, two, because it coats your mouth, it can stay there for hours, giving bacteria a chance to thrive. Brush your teeth or swish well with water after eating peanut butter to encourage washing it out of your mouth completely.

Coffee & Alcohol – You’re probably not surprised that we list coffee and alcohol as bad-breath culprits. Freshly-brewed coffee smells enticing when wafting from the kitchen, but coffee doesn’t have the same effect when you drink it. Coffee dries out your mouth, creating a more acidic, favorable environment for bacteria growth. Ah, yes. The bacteria = bad breath equation strikes again.

And alcohol? It has a similar drying effect to coffee, causing a more acidic pH in your mouth.

Remember that with any odor-causing food or drink, we suggest brushing your teeth afterwards to prevent bacteria. But if you’re out-and-about and don’t have your toothbrush handy, a few good swishes of water around your mouth will help lessen any food debris, clingy sugars or protein, and help hydrate your mouth.  

Lifestyle Habits and Food Choices:

Sometimes what causes bad breath isn’t what you eat or drink but other habits or conditions in your daily life:

Tobacco – Smoking causes its own distinct mouth odor and just like coffee and alcohol, tobacco dries out your mouth, creating an oral environment for bacteria to thrive. Tobacco also irritates gum tissue and smokers also are more likely to have gum disease, which is another source of bad breath.

Extreme diets – Like our earlier example of excessive protein intake, some diet and food choices can affect how your breath smells. Fasting and low-carb eating plans can result in bad breath because the metabolizing of fat for energy (as opposed to sugars) produces a chemical called ketones. This chemical tends to have a strong smell that comes out in your breath.

Dry Mouth –  Xerostomia, a fancy term for dry mouth, can lead to bad breath because there’s not enough saliva to wash away food debris and bacteria. As you might have noticed, dry mouth is related to several other reasons for bad breath.


Many prescription medications list dry mouth as a side effect. You’ll also find that some medications, when metabolized in the body, release chemicals into your bloodstream that affect how your breath smells when you exhale. Medications more likely to cause bad breath include nitrate medications for angina, some chemotherapy medications, and some tranquilizers.

Medical Conditions:

So we’ve covered what you put into your body that can cause bad breath: different foods, drinks, tobacco, alcohol, and medications. But did you know that certain medical conditions can impact your breath? Or that halitosis can also signal certain medical issues like cancer or serious metabolic disorders? 

Here is a list of medical issues that can contribute to having bad breath:

  • Long term sinus problems and post nasal drip
  • Respiratory and tonsil infections
  • Diabetes
  • Liver and kidney problems
  • Certain blood disorders
  • Gastrointestinal issues
  • Chronic acid reflux

Chronic Mouth Breathing We all go through times when we only breathe through our mouth, like when we’re congested because of a cold or allergies. Breathing only through your mouth can dry it out, resulting in the xerostomia we mentioned and cause temporary bad breath. But if mouth breathing is a normal part of your life, you could also be dealing with chronic halitosis. 

Mouth breathing also can affect your jaw alignment, pulling your lower jaw into an underbite. At Davis Orthodontics, Dr. Buddy and the team have seen their fair share of patients with underbites related to chronic mouth breathing. Fortunately, orthodontic treatment like braces or Invisalign® can correct this misalignment. In turn, an aligned jaw can open the airway, addressing chronic mouth breathing and its companion: bad breath.

How to Fix Bad Breath?

So how do you get rid of bad breath? You can try covering up bad breath temporarily with sugarless gum or mints. (Though gum is a no-no if you have braces!)

Pro tip: look for gum and mints sweetened with xylitol, which are sweet but won’t encourage bacteria like other sweeteners can. Gum and mints add that minty scent, but also encourage saliva, which helps rinse sugar and food debris away and lowers your mouth’s pH from acidic to a more healthy level.

We also suggest always rinsing your mouth with water after eating and drinking. And be sure to get your eight glasses of water in every day! Not only is staying well-hydrated good for your overall health, it hydrates your mouth and encourages the production of saliva. In addition to water, a few simple home remedies for bad breath to try include: chewing parsley, eating a serving of plain yogurt daily, and sipping on green tea throughout the day.

Now if we’re talking a long-term cure for bad breath, it goes without saying that practicing good oral care is the number one way for preventing bad breath. A diligent oral care routine takes care of the bacteria that can lead to plaque, tooth decay, and gum disease — heavy hitters when it comes to halitosis. 

Preventing Bad Breath With Braces or Clear Aligners

By now, we all know that brushing twice a day and flossing daily is the standard for keeping a healthy smile. And when you have straight teeth, you have a leg-up on bacteria and plaque — one of the benefits of a straight smile is more effective brushing. But while you’re on your journey to a beautifully-aligned smile with braces or clear aligners, you do have to level up your oral hygiene — we at Davis Orthodontics recommend brushing your teeth after every meal. 

Braces and Preventing Bad Breath 

With braces, food debris has more places to get stuck — brackets and wires provide that much more opportunity for bits and pieces of food to hide and bacteria to linger.

Our tips for stellar oral hygiene with braces? Always floss first, then brush every tooth, bracket, and your wires gently but thoroughly. Either a manual toothbrush or electric will do the job, although an 11-year study did find that using an electric toothbrush resulted in 18% less tooth decay than using a manual one.

As for the best toothpaste for bad breath, your Greer and Simpsonville orthodontist definitely suggests one with flouride to strengthen enamel against tooth decay. An effective toothpaste doesn’t have to have fancy ingredients, but a strong, minty flavor is helpful. Be sure to brush your tongue, palate and inside of your cheeks with toothpaste as well as your teeth!

Finish your oral care routine with a rinse of bacteria-fighting mouthwash and you’ve done all you can to get rid of bad breath.

Invisalign and Fixing Bad Breath

If you’re using clear aligners like Invisalign to straighten your teeth, the same oral care tips apply that we mentioned above, but with the added step of cleaning your Invisalign trays, too. Every time you take them out to eat or when drinking anything other than water, take a few seconds to rinse your Invisalign with water before popping them back in. This helps rid your Invisalign of food debris so you can prevent bad breath.

When you take out your Invisalign clear aligners to brush and floss your teeth at bedtime, take the time to brush your aligners with a soft toothbrush and warm water. Then rinse them before putting them back in your mouth for the night.

Fighting Bad Breath Together

At Davis Orthodontics, we’re experts in straight, beautiful smiles that are healthy, too. Have more questions about fixing bad breath while wearing your braces or Invisalign? Davis Orthodontics is here to help.

If you haven’t taken the plunge with braces or Invisalign yet, book a virtual appointment or contact us today to see us for an in-person consultation at any of our six SC locations: Greer, Simpsonsville, Spartanburg, Clemson, Greenville, Walhalla, or Anderson.