Magical Properties of Saliva
Saliva can heal, help us taste, and even make us feel sexier
Spit, spittle, dribble, drool, slaver, slobber, sputum.
That may sound like a spell from Harry Potter, but it’s just a list of names used to describe saliva. From translation of the Latin word for spittle, saliva has roots in the Proto-Italic “sal-iwo, ” which means “dirty yellow” and “sal-” which means “dirty gray.” Gross, I know, but it says a lot about the state of oral hygiene in the 1400s.
Even though the spit we know and love today is of the colorless variety, that doesn’t mean it’s sterile. Each one of our mouths hosts anywhere from 20 to 30 species of seven hundred possible microbes. The food we eat is also covered in bacteria, which adds to the mix. At any given moment, the average person’s piehole is home to billions of bacteria living in a harmonious biofilm (more if you haven’t brushed your teeth for a few days.) This microbiome is possible because saliva is made of 99% water and makes the environment moist and balmy.
On an average day, we make around 1 to 2 liters of saliva or a bottle of wine’s worth. But that doesn’t mean drinking your own saliva is hydrating. Most saliva is recycled from swallowing. The amount of saliva produced at any given moment also changes under seemingly random circumstances. For example, we make more saliva when we are happy than sad. (Who knew drooling was a sign of joy?) Saliva dries up when we get stressed out. Body position also matters. Standing upright causes more saliva than laying down. So does bright light. The next time your mouth feels dry, try going for a walk in the sunshine with a smile on your face. Even if it doesn’t fix your dry mouth, it may help you forget it bothered you in the first place.
Saliva also has a nearly miraculous ability to heal. That’s because it contains a ton of white blood cells, called neutrophils, and a small protein called histatin. Histatin not only kills bacteria. When researchers put wounded cells in a bath of human saliva, the cells actually repaired themselves. It’s no wonder so many animals lick their wounds. Maybe you should too.