Buzz
Although many people find the idea of saliva unpleasant, it actually serves an essential function in our daily lives. It helps us chew, swallow, and digest food comfortably. Saliva also fights harmful bacteria and plays a crucial role in preventing cavities. Here are 11 interesting facts that might change the way you think about this often-overlooked bodily fluid.
1. Spit is primarily made of water.
Saliva is composed of roughly 99 percent water, with the remaining 1 percent made up of electrolytes and organic substances, such as digestive enzymes, trace amounts of uric acid, cholesterol, and mucins (the proteins responsible for mucus formation).
2. There is a medical guideline for the amount of saliva you should produce.
A healthy person produces between 2 and 6 cups of saliva daily, even without external triggers like eating or chewing gum, which can increase saliva production [PDF].
3. Saliva production follows a circadian rhythm.
Typically, your body generates the most saliva in the late afternoon and the least during the night. Salivation is controlled by the autonomic nervous system (similar to how your heart beats), meaning it occurs automatically.
4. There are five distinct types of saliva.
Salivation occurs in five distinct stages, most triggered by food moving through your system. Not all of these are beneficial. The first stage, called cephalic, happens when you see or smell something appetizing. The buccal phase is your body's reflex when food enters your mouth, aiding in swallowing. The esophageal stage happens as food travels down the esophagus, triggering the salivary glands. The gastric phase occurs when something upsets your stomach, like when you're about to vomit. The intestinal phase is triggered when food that doesn't sit well with you passes through the upper intestine.
5. Spit can fight bacteria.
There's a reason the saying 'lick your wounds' exists. Spit is loaded with white blood cells that fight infections. According to a 2015 study published in the journal Blood, neutrophils—a type of white blood cell—are better at killing bacteria when they come from saliva compared to other parts of the body. So, adding saliva to a wound provides the body with a strong ally in the battle against infection.
6. Spit helps prevent cavities.
The calcium, fluoride, and phosphate found in saliva strengthen your teeth. Spit also combats cavity-causing bacteria, clears food particles from the mouth, and neutralizes the acids in plaque, which helps prevent tooth decay and cavities. This is why chewing gum is recommended by dentists—chewing boosts saliva flow, thereby enhancing your oral health.
7. You need saliva to experience taste.
Saliva serves as a solvent for flavors, transporting dissolved tastes to the taste receptors. It also helps maintain the health of these receptors by preventing them from drying out and shielding them from bacterial infections. Many individuals with dry mouth (or xerostomia) notice a decline in their sense of taste due to the lack of moisture in the mouth. As dry mouth is a common side effect of certain medications, researchers have created artificial saliva sprays that simulate the natural lubrication of real spit.
8. Kissing swaps millions of bacteria.
A 10-second kiss can transfer up to 80 million bacteria, according to one study.
9. Babies don’t drool from birth.
Babies don’t begin drooling until they’re 2 to 4 months old. Unfortunately, they’re also not quite sure how to handle their spit. They lack full control over the muscles in their mouth until they’re around 2 years old, which means they can’t swallow it efficiently. Hence, we created bibs.
10. Stress can leave you without spit.
The body’s fight-or-flight response is meant to prepare you for life-or-death situations, like running from a bear or giving an important presentation. Your heart rate increases, blood pressure rises, and your lungs take in more air. At this moment, digestion isn’t a priority, so the production of saliva, along with other digestive processes, slows down.
11. A lack of saliva was once seen as proof of guilt.
In some ancient cultures, saliva served as a primitive lie detector. In ancient India, accused liars were asked to chew rice grains. If they were truthful, they could spit them out. However, those lying would find their mouths dry, and the rice would stick in their throat.
