Aside from the occasional drool when you smell a delicious meal, your saliva mostly does a silent but wonderful job of keeping your mouth healthy.

“The flow of saliva keeps the mouth clean, free from food debris and masks bad breath,” says Dr Greg Thomas, a dentist at Bupa Dental in Rochedale, Queensland.

Here, he shares some of the best facts about our spit.

Saliva: what’s it made of?

“Saliva is fluid produced and secreted by the salivary gland in the mouth,” says Dr Thomas. “It is composed of 98 per cent water, plus electrolytes, minerals (including calcium and phosphates), mucus, white blood cells, enzymes and antimicrobial agents.

Here are some of the ways it keeps you healthy:

1. Acting as a lubricant

2. Aiding digestion

“It helps by moistening the food you chew, so it can pass easily from the mouth to the oesophagus,” says Dr Thomas. “Enzymes in saliva like amylase and lipase help break down food into simpler nutrients.”

3. Playing a role in taste

“Saliva acts as liquid medium to dissolve food chemicals and carry them to the taste-receptor cells,” he explains. “People with little saliva often complain of dysgeusia, a taste disorder with reduced ability to taste, or having a bad taste all the time.”

4. Defending against decay and disease

“It maintains the pH of the mouth by buffering and neutralising harmful acids in the mouth, and so prevents acid attacks on the teeth that cause tooth decay,” Dr Thomas says. “The minerals in saliva can repair teeth in the initial stages of tooth decay by rehardening the tooth’s enamel.”

Excessive drool

The amount of saliva produced during the day can vary depending on what you are eating and drinking, and it’s normal for salivary glands to go into overdrive when eating spicy or acidic foods, according to Dr Thomas.

“The mouth usually takes care of excess saliva by swallowing more regularly. If this excess is embarrassing for you, try changing your diet.”

Excessive saliva production is called hypersalivation and can be caused by certain medications or medical conditions, such as:

• Allergies and infections
• Sleep apnoea
• Side effect of medications
• Difficulty swallowing caused by stoke or neurological disorders.

Dry mouth

A lack of salvia, also known as xerostomia, can be a common symptom for people who are anxious or stressed.

“Certain medications, medical conditions and treatments can reduce saliva production,” adds Dr Thomas. “They include diabetes, Sjogren’s syndrome (an autoimmune disease that damages the salivary glands), chemotherapy, head and neck radiation therapy, dehydration and antidepressant medications.”

Having too little saliva can become a major problem, as there is less protection against bacteria in your mouth, says Dr Thomas.

To help saliva production and keep your mouth moist and comfortable, he recommends:

• Drinking plenty of water
• Chewing sugar-free gum to promote saliva production
• Using artificial saliva substitutes to moisten the mouth (talk to your dentist about these)
• Rinsing with baking soda to neutralise acids in the mouth
• Maintaining excellent oral hygiene habits.

Talk to a dentist near you

If you have any further questions or would like to in for a check up, contact your nearest Bupa dentist.