Saliva contains lots of different enzymes, some of these are important for digestion e.g. salivary amylase as it helps turn starch in to sugars. If we didn’t have saliva we would also find it difficult to swallow food.
To keep our mouth wet and to start to digest our food when we start chewing.. Our saliva conatins amylase which causes the break down of starch into sugar. so we can then digest and absorb these sugars into our body.
You have three pairs of major salivary glands, and hundreds of minor salivary glands in your mouth and they produce…yes you guessed it saliva!! Human saliva is 98% water, while the other 2% consists of other chemicals such as electrolytes, mucus, antibacterial compounds, and various enzymes (amylase is my favourite because it sounds like “amy” and it breaks down starch – pretty handy thing to have!!).
As part of the initial process of food digestion, the enzymes in the saliva break down some of the starch and fat in the food at the molecular level. Saliva also breaks down food caught in the teeth, protecting them from bacteria that cause decay. Saliva lubricates our mouths to protect the teeth, the tongue, and the tender tissues inside the mouth.
Apparently it also plays an important role in tasting food, by trapping chemicals called thiols!
Some animals use their saliva for other cool stuff as well – swifts use their gummy saliva to build nests and cobras hunt with venomous saliva injected by fangs. Some spiders create thread from salivary glands!! amazing!!