https://www.aeron.com/volume_2_number_1.htm

The Saliva Story - Part 1

Spit is not something most of us like to think about. It has all kinds of negative connotations and cultural associations. Little boys growing up often consider spitting a manly thing to do. Little girls on the other hand are taught that it is unladylike to spit. Spittoons have been commonplace throughout history, but once it was discovered that saliva could carry germs these receptacles quickly fell out of favor. And then there are those ghastly spit balls most of us are introduced to in grade school. Not a pleasant thought. Yet, in spite of what we think about spit, from the time we are born, whether it is the drool on our chin that signals the onset of teething, or the sticky sweet slime that remains on our lips and fingertips after licking an ice cream cone - spit is a presence in our lives. And, as you are about to discover, spit, or saliva, as it is more scientifically known, is a very important bodily fluid.

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The chief functions of saliva, which is mostly water, are lubrication and initiation of digestion. The enzyme amylase, present in saliva, helps begin the breakdown of starches. However, highly complex in both composition and function, saliva does indeed do more than moisten our food and make it easier to swallow. In addition to important enzymes, saliva contains hundreds of other substances - minerals, proteins, hormones, blood cells, and bacteria, to name a few — that form an elaborate protective mechanism for tooth enamel and the oral cavity. The discovery of the immunoglobulin IgA in saliva demonstrated that, along with its role in digestion and oral health, saliva is also active in immune function, helping protect us from foreign invaders. IgA is an important antibody that protects your eyes, nose, throat, intestines, and lungs from infectious diseases.

In addition to being antibacterial, saliva has been shown to be antifungal, antichlamydial and antiviral. Some scientists refer to saliva as a gatekeeper because of its protective role against harmful pathogens and dental caries. But scientific research is showing us that saliva may also be a gateway to simpler, more noninvasive answers to some of our most challenging medical dilemmas.