Saliva is a colorless and thin liquid, which is a digestive juice mixed with the liquid secreted by three pairs of large salivary glands and the mucus secreted by many small mucous glands on the oral wall. Saliva is colorless and tasteless, and human saliva is 99% water. However, saliva is also beneficial to human health. Modern scientific research has confirmed that saliva contains amylase, lysozyme, mucin, globulin, bile iron lactate, calcium phosphate, amino acids, potassium, calcium, chlorine and other essential components for human health. These substances have great health care and health preservation effects on the human body.

Saliva has many health functions, such as lubrication, because saliva contains mucin, which can make the mouth smooth and soft. Can help swallow food. Moreover, saliva contains a kind of "salivary parotid hormone", which can keep people young and make people smart, so that even when they are old, they will be full of vitality and will not be worse than young people. Saliva contains a large amount of amylase, which can hydrolyze starch into maltose and be easily absorbed.

In addition to the above functions, saliva also has antibacterial effect. Because various components in saliva have certain antibacterial and health-preserving effects through different mechanisms, they can prevent inflammation of mouth, throat and gums. Moreover, saliva also has a flushing effect, and toothpaste can only clean the mouth but not whiten the teeth. Saliva can wash away food residues and keep the mouth clean and hygienic. It can be seen that saliva has the function of cleaning teeth and protecting oral hygiene.

Therefore, saliva still has many benefits to people's health. Don't think saliva is useless. Saliva still plays a great role in human health care.