Saliva: role, composition and frequently asked questions

saliva salivation

Saliva is essential for natural functions such as eating and speaking. Its purpose is to moisten the mucous membranes of the mouth and start the digestion of food. This liquid also has other essential functions for the health of teeth. The HELVIDENT team tells you more about the phenomenon of salivation and its role in tooth health.oral hygiene

What's in saliva?

Saliva is a biological liquid secreted by the salivary glands inside the mouth. It is 99 % water. The remaining 1 % includes ions (sodium, potassium, chloride...) and organic elements. Thus, it contains urea, glucose, hormones, RNA and numerous proteins, including digestive enzymes (amylase, lipase).

Several recent studies have demonstrated that salivary pH can be used as a diagnostic biomarker for oral diseases, and even some gastroenterological diseases. The normal pH value of saliva is 7.2. Any variation indicates a pathological condition.

If the pH level is below 7.0, saliva is considered acidic. To reduce it, it's essential to eat alkaline-rich foods such as fruit, vegetables and berries. You can also eat almonds, between 6 and 10 a day, to lower the acidity of saliva.

In terms of the quantity secreted per day, the average adult's salivary flow is around 1 liter per day. Salivation occurs as a reflex action (on contact with food, following a smell or memory, etc.). 

Did you know that we salivate more standing up or lying down and less sitting down? We also salivate more in winter than in summer? Following a spicy meal or strenuous exercise, you may feel a dry mouth. In most cases, a simple glass of water is enough to soothe this unpleasant sensation.

How does salivation affect teeth?

Saliva is a precious ally for oral health, thanks to its multiple roles. First and foremost, it lubricates the oral surfaces. It enables us to speak with ease and chew without injury.

This liquid also helps to rinse away food residues and render acids harmless: wherever saliva can rinse the tooth unhindered, the tooth remains healthy. However, saliva production slows down considerably during sleep. Its protective effect diminishes during the night, hence the importance of always brushing your teeth before going to bed.

In addition, salivation neutralizes the acid produced by plaque, as it contains bicarbonates, phosphates and urea. Dentists in Lausanne and Fribourg speak of its buffering power.

At the same time, it helps remineralize tooth enamel, thanks to the ions it contains (calcium, phosphate and fluoride).

Finally, saliva facilitates food digestion, thanks to the salivary enzymes and amylases it contains. This initial digestion is one of the reasons why it's essential to chew your food long enough to simplify the work of the rest of the digestive tract.

Salivation problems

Protective and disinfectant, saliva also reveals a great deal about our health.  

  • Lumpy, white saliva: a common symptom of Candida Albicans. Caused by a fungus, this infection of the mouth occurs more often in children than in adults. Diabetes and prolonged use of antibiotics are risk factors.
  • Abundant salivation during the night: we've all woken up with a spot of drool on our pillow. Don't worry, it happens to everyone, and it's perfectly normal! During the night, we continue to produce saliva and, in principle, to swallow. However, if your mouth is open and you sleep, for example, on your side, the excess saliva is evacuated... onto the pillow.
  • Abundant or excessive saliva: also known as hypersalivation. Normal in pregnant women, this phenomenon may signal a neurodegenerative disorder.
  • Acidic saliva: you're probably suffering from gastroesophageal reflux disease (GERD). The lower sphincter of the esophagus is no longer functioning properly, allowing gastric juices to flow upwards from the stomach.

If you notice a change in your salivation, we recommend that you report it to your doctor. Bear in mind, too, that salivary exchange encourages the transmission of bacteria, especially those responsible for tooth decay.

HELVIDENT welcomes you to its three dental clinics in Lausanne, Fribourg and Aigle. Our team of experienced dentists provides all types of oral care for children, adults and seniors. Contact us to make an appointment as soon as possible in French-speaking Switzerland.