When I was in medical school, I learned that the human mouth is second only to the colon in harboring horrific deadly germs. A human bite wound can create a devastating infection. When working the ER, I saw plenty of infections from fist fights.
So why is it, that when we cut ourselves, its instinct to stick the wound in our mouth? I know that when Ive sliced my finger cutting my vegetables, the first place I put it is in my mouth — even without thinking. Its not too much different than a dog that licks its own wounds or the wounds of his master! Well, theres an amazing explanation for this.
It turns out that theres a compound in human saliva that greatly speeds wound healing. Furthermore, there are plans to have it mass produced and placed into creams to help heal diabetic and other chronic wounds.
In a new study, the researchers cultured inner-cheek epithelial cells in an experimental dish and a control dish. After the cells formed a smooth surface in both dishes, the researchers nicked the surface of each. They bathed the experimental cells in human saliva. They put saline on the controls.
The saliva soaked cells were nearly completely healed in 16 hours. The control cells still had a gaping wound. The scientists said that your saliva contains a small protein called histatin. We have known about it for a while, but we thought it killed only bacteria. Now we know it also speeds wound healing.
Now we know why we instinctively clean our wounds with our mouth and saliva. Yes, our mouths are loaded with lethal bacteria. Yet its really the status of our immune system and local terrain that determines whether bacteria can get a foothold. We tend to fear bacteria far more than we should. Wed be far better off making sure our bodies are replete with everything they need to function. (Vitamins and minerals from raw fruits and veggies.)
Ref: Federation of American Societies for Experimental Biology, 23 July 2008.