Causes of Bad Breath

Otherwise known as halitosis, bad breath can be caused by certain medical conditions, food habits, unhealthy lifestyle, and poor oral hygiene.
Bad breath can be of two types - transient and persistent. Transient bad breath is temporary, i.e., you can get rid of this type of bad breath by rinsing, brushing, and cleansing of teeth. Persistent bad breath is a relatively serious condition, wherein the problem is of permanent nature. As far as transient bad breath is concerned, the rate of severity varies with causes, like food items having a strong odor (garlic, onion), and smoking. It can be tackled by maintaining basic oral hygiene, dental health, and some lifestyle changes. However, persistent bad breath should be treated after diagnosing the cause.
Generally, bad breath emanates from the mouth itself. Causes of bad breath include diseases, like pneumonia, bronchitis, postnasal drip, chronic sinus infections, chronic acid reflux, liver or kidney problems, diabetes, and respiratory tract infections.
Consumption of Certain Food Items: Consumption of foods (like, garlic, onion) with volatile oils can cause bad breath. These pungent oils are absorbed into the blood stream during digestion. In the lungs, the pungent smell is released into the air, that is exhaled through the nose. Sometimes, bad breath caused by consumption of onion and garlic may last up to 72 hours. The saliva itself can retain a pungent smell for a long period, resulting in bad breath.
Poor Oral Hygiene and Periodontal Diseases: Poor oral hygiene can result in accumulation of food residue in the mouth. Various types of bacteria present in the mouth act upon the food particles, which release hydrogen sulfide vapors, that causes the foul smell. Without regular brushing and flossing, these bacteria along with the food particles, produce a colorless sticky film on the teeth. In the long run, this film transforms to a hard substance called plaque, which can cause tooth decay and periodontal diseases. The cavities formed will house food particles and odor-causing bacteria.
Conditions Affecting the Nose and Throat: Causes of bad breath can be associated with the nose too. Any foreign substance stuck in the nose can give rise to bad breath. It could be due to a sinus infection, which causes discharge from the sinuses to pass through the back of the throat, resulting in a foul smell. Some throat infections also end up with bad breath. Bacterial action in the tonsil can cause a mild bad breath. The main reason for bad breath arising from this area, is the calcified matter formed in the crevices of the tonsil. Such white particles are termed tonsilloliths or tonsil stones.
Use of Tobacco and Alcohol: Both tobacco and alcohol causes drying out of the mouth, which results in a foul odor. Apart from this, tobacco smoke contains tar, nicotine, and other substances; which accumulate in the mouth, causing periodontal diseases and bad breath. Likewise, alcohol consumption may result in digestive problems, which can also be linked to bad breath.
Dry Mouth and Dieting: It is common to feel bad breath when you wake up in the morning. It is due to reduction in saliva production during sleep, as the mouth is kept shut for a longer period. Hence, saliva has a very important role in cleansing and moisturizing the mouth. Accumulation of this oral fluid in the mouth, promotes the swallowing tendency; which in turn helps the mouth in getting rid of the food debris, bacteria, and dead cells. Saliva has the power to kill the bacteria in the mouth. Drying out of the mouth means, reduction in saliva production, and the resultant bad breath. Severe dieting can also cause bad breath, due to the breakdown of chemicals (ketoacidosis) during fasting. In such cases, the breath smells like that of fruits or nail polish remover.
Diseases and Other Causes: Some types of cancer can cause bad breath, but lung infections and abscesses can result in very foul-smelling breath. Kidney failure causes a urine-like smell, whereas a 'fishy' smell is related to liver failure. Even diabetes and chronic acid reflux can cause bad breath. Some people with lactose intolerance may develop bad breath, when they consume milk and dairy products. Dehydration leading to digestive problems and constipation is also among the causes of bad breath. Dentures (artificial devices constructed to replace missing teeth) can also cause this problem, if not cleaned properly.
Bad breath can be caused by any of the reasons stated above. Maintaining oral hygiene by regular, brushing, flossing, and rinsing, is the solution for bad breath. Always remember to clean your tongue with a toothbrush or tongue cleaner; because a coating of food debris, dead cells, postnasal drip, and bacteria is formed continuously. If proper cleaning of the mouth does not provide any relief, then consult your health care provider or a dentist.
Disclaimer: This article is for informational purposes only, and should not be used as a replacement for expert medical advice. Visiting your physician is the safest way to diagnose and treat any health condition.