There are moments when a waiter walks by you with a steaming hot Italian pizza while waiting for food at a restaurant and your mouth starts watering. But why is this happening? What makes the ‘mouth-watering’ expression so precise? Science has a response.
First, knowing exactly what saliva does is crucial. As it is step one in breaking down foods, it plays a significant role in the digestion process. 99.5 percent water and 0.5 percent proteins, lipids, and electrolytes make up the saliva.
A signal is sent to your brain’s primary salivary centers in the medulla oblongata when food is smelled, seen or even thought about. Neurotransmitters such as acetylcholine and norepinephrine that trigger nerve impulses are released by the brain, telling the glands to generate saliva.
Near the upper teeth, under the tongue and on the floor of the mouth, large salivary glands are located. In the lips, inner cheeks and other linings of the mouth and throat, small glands are found. Up to two liters of saliva a day can be made, which moistens your mouth, protects your teeth against decay, and, most importantly, initiates digestion. It contains enzymes that, before it enters your stomach, begin to break down food.
Back to digestion now. Saliva has enzymes that help to break down food, which is why digestion is so necessary. The stomach would have a harder function in digestion without these enzymes, which may suggest less nutrient absorption and more tummy aches. SPIT obviously allows us to be safe.
And how does all of this relate to the cause for salivating? Ok, straightforward. Production of saliva is a part of a reflex mechanism. The primary salivary core, our medulla oblongata, which tells the brain and body to get the food enjoyment party underway, sends a signal to smell, see, or visualize eating food. At this stage, to begin producing more saliva, the brain releases acetylcholine and norepinephrine.
So that is the science behind it, but some psychology might also be involved. Another reason is that it is a reflex which is conditioned. That implies that we learn to equate certain foods with certain pleasures as infants. For instance, chocolate cake is a round, brownish cylinder, and chocolate cake is delicious. We learn this reflex, which means that we respond as long as we can actually eat the foods we see or smell when we see similar formed foods.
Now take out that napkin when you see food go by…
Check out my related post: Is bluetooth dangerous?