Why does the mouth smell foul after a long night's sleep?

Photo: Rajeev Bhatt

Amol Chaurasia, Lucknow

Bad breath in the morning is mostly attributed to a lack of saliva. During the day, your mouth produces a significant amount of saliva, but while you sleep, saliva production goes down.

Saliva is critical for sweeping away the food particles that would otherwise linger and collect bacteria.

A decrease in saliva production increases the likelihood of dry mouth. This allows bacteria to grow and produce volatile sulphur compounds (VSCs), which is what smells bad. Bacteria munch on compounds, proteins, amino acids, and leftover foods that are stuck in your mouth and teeth to produce these VSCs, which causes the bad odour.

The way you sleep can also affect the intensity and frequency of morning breath. Snoring or breathing through the mouth at night can increase the likelihood of bad breath. Most mouth breathers sleep with their mouth open, causing their mouth to get drier and therefore letting bad-breath-causing bacteria flourish. Basically, any time you reduce saliva in the mouth, you reduce the mouth’s ability to fight the bacteria that causes the bad breath.

Dolly Rohira,Bengaluru

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