This is an I-Heart podcast.

Welcome to Brain Stuff, a production of IHeart Radio.

Hey, Brainstuff, Lauren Wollebaum here.

Saliva.

It's not the kind of thing that comes to mind often.

Sure, you might notice it when you

smell the smoke coming off of barbecue, or the lack of it when you're about to give a presentation.

But a seemingly inconsequential thing, like spit, actually plays an important role in our health

and in the way that our food tastes.

Saliva is 99% water.

The remaining 1% is made up of, well, lots of stuff, including digestive enzymes, uric acid,

electrolytes, mucus forming proteins, and cholesterol.

It's also home to more than 700 types of microbes, including bacteria and fungi.

The actual makeup of our spit varies from person to person, and each person's saliva fluctuates due to factors like age, hormonal influences, and various stimuli. As is the case with mucus, our bodies are constantly producing saliva. Throughout

the course of a day, your body churns out about two to four pints of it, that's one to two liters.

Most of that saliva production occurs in the afternoon and tapers off at night when we tuck into bed.

We don't completely stop salivating when we sleep,

which explains why some side or belly sleepers wake to discover that they've drooled on their pillow.

Saliva is produced in the salivary glands, which are found in the tissues of our mouth.

These glands are made up of clusters of cells that secrete saliva through a series of collecting ducks out into the mouth.

There are three major pairs of salivary glands.

The parotid glands are the largest. They're located on both sides of your face in front of your ears.

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