Is Saliva as Gross as It Sounds?

daughter checking teeth of her mother
Saliva. Everyone has it to some degree or another. Usually, it isn’t something we give much thought to until we see it, like someone spitting in public for example, or until there is some issue in our mouths.

We know that spitting in public is gross, and it’s rude. But what about spit itself, when it stays where it’s supposed to be? While it may be wet and sloppy, and it certainly is necessary for good oral health, is it gross?

The short answer is that no, saliva is not intrinsically gross or disgusting when you look at it for what it is. It’s an important bodily fluid that is used primarily to rinse your teeth and help accelerate the breakdown of food.

When you look at saliva from a microbiology standpoint, it is a rich and vibrant ecosystem of various flora. Saliva also has high levels of many hormones as well. While this also doesn’t mean it’s necessarily “gross”, it means that it certainly isn’t sterile.

That also means it isn’t meant to be a cleaning agent for anything other than your teeth, so stop using it to clean your glasses or contacts. Now that’s gross, and dangerous as well since it can lead to infections.

We are going to take a closer look at saliva, what it is, what it does, why we need it, and if it boils down to it being “gross”. You might need to grab a mint, maybe some nice filtered water, because you could say that we are going to do a deep dive, into saliva.

What’s In It?

The secret is always in the sauce, so first thing’s first, we need to know what saliva is made of. It is made up, just like the human body, of a large portion of just water. 99%, in fact, is simply water.

The last percent is all the stuff that makes spit, spit. There is a strong presence of electrolytes and other organic substances that are found in the body, such as enzymes, acids, mucus-building proteins, and even some cholesterol.


Saliva features eight electrolytic elements, iodine, phosphate, bicarbonate, chloride, magnesium, calcium, potassium, and sodium. Several of these contain lower levels of the electrolyte than are present in blood plasma, the opposite is true as well, with saliva having several in quantities higher than are found in blood plasma.


There are a few different enzymes in saliva. One of the most useful to those of us who love our carbs is ptyalin which begins digesting difficult starches before they are even done being chewed. This is extremely important because many of those starches are incapable of being digested without that little headstart.

There are a number of antimicrobial enzymes that help kill certain types of harmful bacteria in the mouth. These enzymes include immunoglobulin-a and Lactoferrin. There are additional antibacterial compounds present such as thiocyanate and hydrogen peroxide. These are all meant to keep harmful oral flora in check.

There are enzymes such as proteins that are rich in proline that helps build the enamel that protects teeth. Proline-heavy proteins are also responsible for helping to bind and sequester calcium in the teeth for optimal strength and integrity.

Extra Goodies

There are a wide variety of substances that are present in saliva beyond the basic electrolytes and enzymatic components. There is mucus, as well as components like glycoproteins and mucopolysaccharides, which are used for repairing the mucus membranes found in the mouth.

Similarly, a substance called EGF, Epidermal Growth Factor, is present. EGF has roles in healing oral and gastroesophageal ulcers, DNA synthesis stimulation, and mucosal protection from caustic bodily fluids like bile acids and gastric acids. The primary function of EGF is to stimulate the growth of epithelial and epidermal cells.

Additional beneficial substances found in saliva include Opiorphin, which is a mild pain-killer, Haptocorrin, which helps the body absorb vitamin B12 before the digestive system destroys it.

There is often a large volume of bacterial cell volume per milliliter, which leads to a large volume of bacterial waste and by-products. These by-products contain compounds like organic acids, thiols, amines, and amino. When present in large enough quantities, these substances can be responsible for saliva having a bad smell.

One last thing that is present in saliva in often surprising amounts, is hormones. While researchers are not entirely sure why there is such a significant level of hormones in spit, there are some theories. One being that a potential mate may be able to subconsciously discern the fertility or genetic compatibility of the member of the opposite sex. Another theory says that since there is quite a lot of testosterone in the saliva, it may play a role in enhancing attraction or foreplay.

What Does Saliva Do?

The popular myth is that saliva is only needed to keep your mouth wet. It makes talking, eating, and of course, kissing, much easier and more enjoyable. But there’s a lot that saliva does that gets missed by the general population. Not only does it keep your whistle wet, but it helps digest your food, protect your teeth, and even heal your mouth and gums.


Salva’s digestive functions are not limited to helping your teeth masticate, it also helps to form food into what is called a bolus. A bolus is a ball of moistened and chewed food that is being readied for swallowing and additional processing. The moistening action of the saliva allows the bolus to pass freely through the esophagus.

One of the enzymes present in the saliva is ptyalin, which helps to start breaking down the starches into simple sugars like, dextrin and maltose. These simpler sugars can be utilized much more effectively by the small intestine. Nearly a third of all starch digestion takes place in the mouth. The fats are also being digested by the lipase, which in its salivary form gives the pancreatic lipase a head-start.


girl smiling with flower bouquet in hand


Saliva is also the primary oral lubricant. The inside of the mouth and the mucus membranes are incredibly delicate and sensitive. Coating of the oral surface keeps it protected mechanically while eating, chewing, and swallowing, and it facilitates more comfortable and easily annunciated speech.

Conditions that reduce the volume of saliva can lead to increased soreness after eating many foods. Another complication is that food, dry foods in particular will stick to the inside of the mouth and esophagus. This can not only be uncomfortable but it can be dangerous.

This lubrication also helps rinse away and remove leftover food and other debris, helping to keep teeth whiter. This helps reduce the proliferation of the bacteria that feed on leftover sugars and create plaque and decay.


Saliva, it turns out, is incredibly important in taste getting from food to your brain. Taste is sensed by your taste buds, but they function best when there is a liquid medium in which the food particles are carried. When you chew your food up, it mixes with saliva and that causes it to be experienced to a much more significant degree.

Having too little saliva means you could suffer from taste dysfunctions. Without a reliable liquid medium to allow the taste buds to function optimally, people often report a reduced ability to taste or that their food tastes bad and often metallic much of the time.

Other Essential Functions

Saliva also helps maintain the pH environment of the mouth. Since it is supersaturated with various ions already, being combined with other proteins that prevent salt precipitation lets the surplus ions act as a buffer that helps keep the mouth within approximately half of one point to either side of pH 7.0.

This is crucial to preserving the integrity of the minerals that keep your teeth hard. If saliva were any more acidic it could begin to dissolve your teeth. But it serves an additional purpose in protection, it helps to neutralize other acids that would work to decay your teeth, causing sensitivity and even pain. If you have had some of the enamel wear and are experiencing some sensitivity, you may want to look into something to help desensitize and seal your teeth against further damage.

Saliva Production

girl using floss to clear her teeth


Saliva is produced by two sets of salivary glands, and in the average adult, they produce an average of 25,000 quarts of spit during the course of their life. When this production is not up to levels needed to maintain function the resulting dry mouth can be uncomfortable as well as a contributing factor to bad oral health.

While people think that dry mouth is something you fix with a quick glass of water, it is not that easy. If there is an underlying condition responsible then the negative effects brought on by the lack of saliva won’t be avoided no matter how hydrated you are. The best way to stimulate production, however, is drinking plenty of water each day.

Saliva Can Help Save Lives

woman holding smiling sign in hand


Not only does saliva have the ability to protect the tissues and teeth in your mouth, help you to chew, process, and digest your food, but it also contains a full record of your genetic makeup as well as other biomarkers that can be used to identify potential medical matches.

Many modern diseases like blood cancers require bone marrow transplants to successfully combat them. While older donor screening processes often required blood draws, lab workups, and more, there are modern techniques for screening people based on the genetic information in their saliva.

The enzyme-linked immunosorbent assay or ELISA, PCR or polymerase chain reaction, and high-resolution mass spectrometry are all used with saliva to diagnose diseases or disease states. Some of the conditions screened for include Cushing’s disease, HIV, several cancers, allergies, and hypogonadism.

Saliva and tissues from the inside of the mouth can be swabbed to determine if one person is a genetic bone marrow match for another by way of human leukocyte antigen, or HLA, testing. This can tell if one person can donate bone marrow to another to aid in the treatment of bone and blood cancers. Once the test is done, the information on the donor is added to the registry, and if a doctor finds a potential match for their patient, the donor is contacted to see if they can be reached for donation.

What’s the Verdict, Is Saliva Gross?

When it comes down to it, saliva is just like many other bodily fluids, and arguably a lot less gross than a bunch of them. But can we really call it gross?

Sure, it can get a little smelly, but that is generally a function of the personal and oral hygiene of the person with the stinky spit. Yeah, it’s definitely got some bacteria in it, but really what doesn’t? Spitting in public is always gross, so that’s just a given.

The upsides are that it has a lot of useful functions, like helping to keep your teeth clean, and helping to keep the oral environment hospitable to teeth, rather than the corrosive mess it might be without a little acid-neutralizing mouth sauce thrown in.

It also helps protect your mouth, chomping a nacho that’s flipped awry is bad enough, but can you imagine trying to swallow all that without any saliva? Yikes. Sometimes I can barely chew my food like a normally functioning human without punishing my tongue or the inside of my cheek, and my salivary glands work just fine.

All in all, no, saliva isn’t gross. It’s fluid from your body, so you should try to keep it in your body, but in the grand scheme of things, it definitely is pretty far down the gross list from some other stuff our bodies make. Plus, when you throw in that it might even help us subconsciously locate compatible mates, it actually starts to sound pretty cool.