Did you know that the main cause of bad breath is not due to the food we eat, but because of the bacteria in our mouth? These bacteria produce what we call Volatile Sulphur Compounds (VSCs) that are responsible for the unpleasant odour we often refer to as halitosis.
In this article, we will delve deeper into:
What Volatile Sulphur Compounds are;
How they affect our oral microbiome;
Their symptoms and effects;
And most importantly, how we can get rid of them.
What are Volatile Sulphur Compounds?
Volatile Sulphur Compounds, or VSCs, are sulphur-containing organic compounds that are formed by bacteria that live in our mouth. They are responsible for the unpleasant smell that often accompanies bad breath.
VSCs are formed when oral bacteria break down food particles in our mouth, especially those that are high in protein. When these foods are broken down, they release amino acids that oral bacteria feed on, and as a by-product, they produce VSCs.
The most common VSCs produced by oral bacteria are Hydrogen Sulphide, Methyl Mercaptan, and Dimethyl Sulphide.
Hydrogen Sulphide
Hydrogen Sulphide is the most commonly found VSC in the human mouth. It is known for its strong, unpleasant odour that is often described as being ‘similar to rotten eggs’. Hydrogen Sulphide is produced when food particles are broken down by oral bacteria.
Methyl Mercaptan
Methyl Mercaptan is another VSC that is often found in the human mouth, and it is known for its extremely foul odor. Methyl mercaptan is produced by certain types of bacteria in the mouth, such as Treponema denticola, and it is also produced when proteins are broken down by oral bacteria.
Dimethyl Sulphide
Dimethyl Sulphide is the least commonly found VSC in the human mouth, and it is known for its ‘cabbage type’ odour. DMS is produced by certain types of bacteria in the mouth, such as Prevotella intermedia, and it is also produced when amino acids are broken down by oral bacteria.
Volatile Sulphur Compounds and Bad Breath
VSCs are the main cause of bad breath. When these compounds are produced in excess, they can create a foul smell that is often described as “rotten eggs” or “sulphuric”. People with chronic bad breath, or halitosis, often struggle with social interactions, personal relationships, and even career advancement.
If you suffer from bad breath, it is important to take action to address the underlying cause, which is often the overgrowth of oral bacteria.

Volatile Sulphur Compounds and Periodontal Disease
According to the Centers for Disease Control and Prevention (CDC), periodontal disease is a common dental problem that affects the gums and supporting tissues around the teeth. The disease can range from mild inflammation to more severe cases that cause tooth loss.

The CDC reports that almost half of adults in the United States over the age of 30 have some form of periodontal disease. Risk factors include smoking, genetics, poor oral hygiene, and certain medical conditions.
If left untreated, periodontal disease can lead to serious health problems, such as heart disease, stroke, and respiratory disease. It can also make it more difficult for people with diabetes to control their blood sugar levels.
Fortunately, there are steps people can take to prevent periodontal disease, such as brushing twice a day, flossing regularly, and seeing a dentist for regular checkups and cleanings. For those who already have the disease, treatment options may include deep cleaning, medication, and surgery.
Periodontal disease is a common and serious dental problem that can lead to other health issues if left untreated. However, with proper oral hygiene and regular dental checkups, it can be prevented and treated.
How Do You Get Rid of VSC in Your Mouth?
The best way to get rid of VSCs in your mouth is to maintain good oral hygiene. Yes – I know you’ve heard this advice everywhere but it’s true!
Brushing your teeth at least twice a day, flossing regularly, and brushing the tongue is essential in removing the dreaded VSCs in your mouth.
Using mouthwash to kill the bacteria that cause bad breath can help but DO NOT overuse mouthwash – it kills all bacteria including the good bacteria. Check out this post on the balance of good and bad bacteria and the magic of dental probiotics.

Taking oral probiotics that contain strains such as Streptococcus Salivarius K12 is another effective way to reduce the levels of VSCs in your mouth. These probiotics work by replacing the harmful bacteria in your mouth with beneficial bacteria that produce antimicrobial substances, which can help reduce bad breath and improve overall oral health.
Other factors such as staying hydrated, avoiding foods that are high in onions and garlic, quitting smoking, and chewing sugarless gum can all help reduce the levels of VSCs in your mouth.
FAQs
What causes volatile sulphur compounds?
Volatile Sulphur Compounds are caused by the breakdown of food particles in our mouth by oral bacteria. Poor oral hygiene, dry mouth, and certain medical conditions can all contribute to the overgrowth of oral bacteria and the production of VSCs.
Can volatile sulphur compounds cause periodontal disease?
Yes, the overgrowth of oral bacteria and the production of VSCs can contribute to periodontal disease, which is an infection of the gums and bones that support the teeth.
How do volatile sulphur compounds cause bad breath?
Volatile sulphur compounds cause bad breath by creating a foul smell that is often described as “rotten eggs” or “sulfuric”. When these compounds are produced in excess, they can create an unpleasant odour that is noticeable to others.