Saliva – just liquid in our mouth?
Saliva is so much more than just the liquid in our mouths. In fact, it’s hard to imagine what we would do without saliva. Our mouths would be dry, and most probably also sore and itching. It would also be very hard to process, swallow and taste food. Saliva is a very important fluid in many ways. So what is it? It’s essentially a liquid that is constantly being produced by our salivary glands, which consists of approximately 98% water, plus other important substances such as mucins, electrolytes, antibacterial compounds, enzymes, proteins, minerals and more.
How is saliva produced?
The production of saliva is the work of three major salivary glands, and many smaller glands around the mouth. The response of this system to external factors is fascinating – the salivary glands really kick into action not only when you eat, but also when you so much as just think about food or smell something delicious. The adult’s oral cavity produces approximately 2 to 6 cups of saliva per day. When stimulated by food or chewing gum, it goes up to an incredible 2 litres a day!
Why do we need saliva?
The first phase of digestion takes place in the mouth, by mixing the chewed food with saliva. For example, starch and fat start to break down thanks to the enzymes contained in saliva. But there are other very important functions of saliva. Thanks to its antimicrobial abilities it is a very strong fighter against various mouth diseases, including teeth caries.
Saliva is able to destroy many bad bacteria and keep the mouth clean and protected. It is also a very strong player when it comes to various antibacterial responses. This wonderful liquid contains lysozyme, peroxidase and lactoferrin, or IgA-type antibodies – substances that prevent pathogenic microorganisms from endangering the soft and hard mouth tissues. Thanks to the presence of saliva’s healing and nourishing compounds, it can effectively heal wounds and improve the condition of fine oral tissues.
Have you ever seen a dog or a cat licking their wounds or scratches? What do you instantly do when you cut your finger on paper or while preparing food? Exactly, you lick your finger without any further thinking. Not only dogs and cats, but also humans, and other species have the natural need to heal their wounds quickly. It’s an instinct to lick the wounds because our body knows that the ultimate and essential antimicrobial and healing agent that is always there, is our own saliva.
Did you know?
During the past decades, salivary diagnostic tests have been very helpful in diagnosing various diseases and conditions. Thanks to saliva, we are able to diagnose various bacterial, yeast and viral counts which indicate caries activity and altered immune responses, as well as many oral and systemic diseases, hormonal imbalances or to identify steroids and sex hormones present in one’s system. They have also been of great help during the Covid-19 pandemic: there have been various different types of test developed, but it’s the saliva tests that have shown to be the most accepted not only amongst adults, but also amongst children.
Why does my mouth feel dry and what should I do?
This problem occurs when there is not enough of this health-supporting fluid in one’s mouth. The condition of our body not being able to produce satisfactory amounts of saliva is called xerostomia. Xerostomia is represented by a feeling of dryness in the mouth, or a noticeably reduced amount of saliva in the mouth. Patients with xerostomia have been shown to be at higher risk of developing tooth decay and infections in the oral cavity. This condition also arises as a side effect of some types of medication (e.g. antidepressants, antihistamines, sedatives, etc.), diseases (e.g. diabetes) and medical treatments (e.g. after radiation and chemotherapy). It is also a side-effect of dehydration caused by insufficient fluid intake or excessive ingestion of e.g. alcohol or coffee.
Xerostomia can also be caused by stress, anxiety and hormonal changes. This condition may be treatable, but a visit to a specialist is often inevitable. If you experience any of the symptoms from the list below, you should consult with your dentist and ask them for advice on how to proceed with this health issue. There are also artificial saliva products available for incurable cases.
For immediate help, try to hydrate more – drink more water and use oral care products that enhance saliva function. It is good to avoid foods that are salty, spicy or acidic, and also avoid drinks with caffeine or alcohol, all of which can dry out your mouth.
If you’ve noticed persistent dry mouth signs and symptoms, make an appointment with your doctor.
According to the Mayo Clinic, if you’re not producing enough saliva, you may notice these signs and symptoms all or most of the time:
- Dryness or a feeling of stickiness in your mouth
- Saliva that seems thick and stringy
- Bad breath
- Difficulty chewing, speaking and swallowing
- Dry or sore throat and hoarseness
- Dry or grooved tongue
- A changed sense of taste
- Problems wearing dentures
Saliva and enamel protection – how are these two connected?
The bacteria that form dental plaque also, while forming this biofilm and plaque, create an acidic environment. If teeth are in an acidic environment for too long or too often, the minerals within the teeth start to dissolve, and subsequently the enamel is gradually weakened due to this outflow of important minerals.
This is where saliva once again comes into play. This fluid washes the surfaces of the teeth, helping protect them thanks to saliva’s cleaning properties. Saliva also contains mechanisms to neutralise the acidic environment in the mouth, and at the same time ensures remineralisation. The important minerals are re-incorporated into the enamel either directly from the saliva, or thanks to a saliva-toothpaste mixture made from mineralised toothpastes.
Saliva is an essential part of teeth protection when it comes to fighting caries, and supporting your mouth’s natural healing and protecting properties.
Why should we use toothpaste when saliva already works for healthy teeth?
Saliva changes its composition according to many factors. The ideal scenario is when it is balanced, and that can be very effectively supported by our lifestyle choices – quitting smoking, eating a healthy and balanced diet, and also by a careful choice of toothpaste.
Toothpaste is also a solution when it comes to maintaining fresh breath. It feels good to have freshly clean teeth, and one of the main functions of toothpaste is to bring us this confidence of fresh breath after brushing. Another function is connected to safe abrasiveness: saliva is not abrasive at all, and sometimes we need to get rid of certain food compounds with a little extra help from abrasive microparticles. This mainly applies when we enjoy meals or drinks that are naturally staining to the enamel, for example red wine, coffee and certain spices. In order to have naturally bright teeth, it is important to use a toothpaste with a safe level of Relative Dentin Abrasion (RDA).
When we talk about toothpastes, it is important to choose one that will help with maintaining the natural balance in the mouth. Considering everything mentioned above, the best toothpaste for one’s oral health is one that supports the natural protecting properties of saliva. A good toothpaste should therefore not contain any aggressive ingredients, and should also contain the best possible compounds that work in favour of saliva.
DOSTÁLOVÁ, Taťjana. SEYDLOVÁ, Michaela et al, Stomatologie. 1. edition. Prague: Grada Publishing, a.s., 2008. Number of pages 196. ISBN 978-80-247-2700-4.