Bad breath comes about as a result of poor oral health. However, underlying health issues could be the culprit. By EVE MOSONGO

About 10 per cent of the causes of halitosis are due to ailments outside the mouth. Identifying the type of smell that comes from your mouth can help you pinpoint its origin.

Let us look at some causes of bad breath.

 1. Lung infections

Bad breath is also caused by pneumonia, tuberculosis, lung infections and bronchitis. Dr Lin states that, “Lung cancer usually causes a distinct bad breath, and breath is now being used in early detection. If lower respiratory tract infection presents with increased mucus production, it may be hard to determine the cause of bad breath.” Unfortunately, other than time and treating the source of infection, this type of bad breath has no other cure.

People suffering from lower respiratory tract diseases such as asthma and cystic fibrosis are also prone to bad breath. Asthma patients are more likely to suffer from dry mouth – the illness restricts air flow through the nostrils thus one has to breathe through the mouth. Cystic fibrosis, a genetic disease, affects the lungs, sinuses and digestive tract

2. Menstruation

Bad breath in women increases before and during their period. While oral bacteria levels are the same across both genders, women have lower saliva levels during menstruation, which may account for the bad breath.

3. Under medication

At times, when you’re under medication, you’ll notice that your breath changes. Many drugs can cause your saliva to dry. The most common medication that might leave your mouth dry usually treat Parkinson’s disease, asthma, hypertension, epilepsy, acne, depression, anxiety and obesity. If you’re suffering from any of these illnesses and you experience bad breath, ask your doctor to switch up your drugs. Also, avoid coffee as it can worsen the dryness.

4. It is genetic

A disorder known as Trimethylaminuria , aka fish odour syndrome, causes body odour too. This genetic disorder affects the ability to break down choline, in turn leading to a buildup of trimethylamine. At times, the odour smells like rotten eggs, urine or garbage. The odour is excreted through sweat, urine, saliva and blood. The fishy smell is also exhaled through the nostrils and mouth.

What can you do? If suffering from TMAU, reduce your intake of foods rich in choline such as broccoli, legumes, liver, kidney, eggs and beans.

5. Late stage liver failure

Late stage liver failure is also a cause of bad breath. This can be identified by a sweet, musty aroma. Cirrhosis causes an odour that smells like rotten eggs or decayed blood. And, at times, the liver is the source of halitosis.

6. On low carb or keto diet

When on these diets, you may be forcing your body to burn fat for fuel. As a result, you may be producing chemicals known as ketones which are released in your breath. These produce an acetone or a fruit and nut odour. Fasting or regularly skipping meals reduces the amount of saliva in your mouth. This may lead to a sulfuric odour as a dry mouth prevents clearance of harmful bacteria.

7. You have diabetes

Diabetics are prone to ketone breath as they don’t produce enough insulin in their bodies. This causes them to burn fat, which produces ketones. Chronic kidney failure also causes bad breath in patients suffering from this disease. Their breath may also smell like ammonia. Their saliva contains a high amount of urea which, when broken down to ammonia, causes the smell.

8. Digestive problems

According to Dr Steve Lin, author of The Dental Diet, “The digestive system causes many cases of bad breath. Any condition that allows air from the stomach to move up into the esophagus and the oral cavity may cause halitosis.” He adds that bad breath caused by the gut is usually a sign of general imbalance in the digestive system. Some of the digestive causes include constipation, bloating, and gastroesophageal reflux disease.

9. Bad sinuses

Microbial build and infected sinuses can cause bad breath. Sinusitis (inflammation of the nasal sinuses) and nasal polyps (soft, jelly-like overgrowth of the sinus lining) can cause bad breath as they encourage the buildup of microbes.


 10. Tonsil breath

When food debris, mucus and bacteria get trapped in the crevices of your tonsils, this leads to a buildup, hardening and formation of tonsil stones. These, along with throat mucus, are a sign of nasal problems that cause bad breath.