Bad Breath – What causes it? How to treat it?

Bad breath, medically known as halitosis, can be caused by poor oral hygiene and may be a sign of underlying health problems. Bad breath can be humiliating and, in rare situations, induce anxiety. The types of foods you eat, as well as other harmful lifestyle practices, can aggravate bad breath. Take action with the help of your dentist at Manor Lakes Dental to prevent and treat halitosis.

Medically Reviewed by Dr. Sirisha Penmetcha BDSC, FRACDS on

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What causes the smell (bad breath)?

Sulphur-producing bacteria that dwell on the surface of the tongue and in the throat are the most common cause of halitosis (bad breath). These bacteria break down proteins and release odorous sulphur compounds.

Causes of bad breath (halitosis) include strong foods, smoking, cavities, gum disease, sinus, mouth or throat infections and diseases.
Causes of Bad Breath

Other common causes of halitosis include:

  • Poor oral hygiene.
  • Gum disease or Periodontitis – build up of plaque on your teeth.
  • Infections or persistent inflammation in the nose, sinuses, or throat (tonsils), which can lead to postnasal drip.
  • Medicines, alcohol, and stress can all produce dry mouth and bad breath.
  • Smoking which deprives the mouth of oxygen.
  • Acid reflux from the stomach
  • Chronic sinusitis which might cause post-nasal discharge.
  • Dieting

Does food affect your breath?

In a nutshell, digestion starts in your mouth. If you eat food with strong scents (such as garlic or onions), brushing and flossing, as well as mouthwash, will only mask the odour. The odour won’t totally go away till the foods have passed through your system.

Foods with a strong odour like garlic, onions, cauliflower, cheese, fish, processed foods like ham and alcohol casue bad breath
Strong foods that may cause bad breath

Food that can cause bad breath include:

  • Foods with a strong odour like garlic, onions and cauliflower
  • Fish
  • Cheese
  • Processed foods like ham
  • Alcohol
  • Dieting – When your body breaks down fat due to lack of food, chemicals are released, which can make your breath smell bad.

Does poor oral hygiene cause bad breath?

Food particles can remain in your mouth if you don’t brush and floss your teeth (or dentures) on a daily basis, increasing bacterial growth between teeth, around the gums, and on the tongue. This results in foul-smelling breath and gum inflammation (gingivitis).

Tobacco, whether smoked or chewed, canirritate your gums, discolour teeth, prevent your ability to taste food and cause bad breath.

How do you know if you have halitosis?

Bad breath is casued by bacterial build up

You should be able to tell if your breath has an odour (rotten egg smell) by licking your wrist, letting it dry for a bit, and then taking a whiff. You could also smell your floss (after flossing back teeth) or use your toothbrush or a scraper to gently scrape the back of your tongue, then sniff the scraper.

The following symptoms may also indicate halitosis (bad breath):

  • Bad breath and a burning tongue in the morning.
  • Your tongue is covered in a white coating, especially at the back.
  • You have a dry mouth.
  • Buildup on the gums and teeth.
  • Mucous, or post-nasal drip.
  • A frequent desire to clean your throat and thick saliva.
  • A persistent sour, bitter metallic flavour.

How to treat bad breath?

Tongue scraper

The treatment for bad breath will be determined by the cause of the condition.

  • Maintain excellent dental hygiene – i.e. brush and floss after every meal. Carry a toothbrush to school or work or use antispectic mouthwash. Clean your braces and dentures as prescribed by your dentist. Dentures should be taken out at night and carefully cleaned before being reinserted the next morning. Clean your tongue using tongue brushes and scrapers.
  • Book an appointment with your local dentist at least twice a year. At Manor lakes Dental we’ll perform an oral examination and professional teeth cleaning, and we’ll be able to detect and treat periodontal disease, dry mouth, and other issues that could be causing bad breath.
  • Quit Smoking and chewing tobacco. Consult your dentist for advice on how to quit smoking.
  • Drink lots of water to keep your mouth moist. Sugarless gum or candy can stimulate the production of saliva, which helps wash away food particles and bacteria.
  • Consume less meat (particularly proceesd meat like ham and salami). Eat more fruits and vegetables to eliminate plaque and food particles from your mouth.
  • Keep track of the foods you consume. Bring the log to your dentist for review if you suspect they’re the source of your bad breath.
  • Bad breath may be caused by some medications. Make a list of all the medications you’re taking.
  • People with chronic sinusitis may benefit from using a saline nasal spray on a daily basis.
Dental Plaque
Dental Plaque can cause bad breath – Before and After a quick clean

Consult your dentist at Manor Lakes Dental if your bad breath persists after making these lifestyle modifications.

Call 03 9742 4533


Here are some additional resources to help you:

  1. WebMD – Dental Health and Bad Breath
  2. Better Health – Halitosis or bad breath
  3. Healthline – Bad Breath (Halitosis): Causes, Symptoms, and Diagnosis

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