Buzz
Here’s a gross but interesting tidbit: Your salivary glands generate between one to two liters of saliva daily. Our teeth are essentially submerged in it, but we typically don't notice saliva unless it's splattering out of someone’s mouth. Too bad, because despite its icky nature, saliva is one of the most intriguing substances on Earth.
10. Salivary Gland Stones
Heads up: The video above shows the removal of a salivary stone, and it's not for the faint-hearted.
Time for a health check. Is your mouth feeling dry? Are you experiencing neck pain or swelling? Any difficulty swallowing food? If you said 'yes,' you could have a salivary stone. Trust me, it’s as unpleasant as it sounds.
Salivary stones, also known as sialolithiasis, are essentially kidney stones in your mouth. Since saliva contains calcium, sometimes it forms hard, pale crystals that block the salivary ducts. While the cause remains unclear, dehydration, poor diet, and certain medications are believed to play a role.
In addition to being unpleasant, salivary stones tend to be more common in adults and males. They can grow to massive sizes, with some stones reaching up to seven centimeters (2.8 inches). These giant calcified masses block the flow of saliva, leading to painful swelling and potential infection.
If you suspect a stone in your mouth, what should you do? The solution depends on the size of the stone. Small ones might be dislodged by sucking on sour candies, which stimulate saliva flow and can flush out the blockage. Sometimes, doctors massage the ducts to gently push the stone out. For larger stones, dentists may use shock waves to break them apart. A technique called sialoendoscopy uses a tiny camera and specialized tools to remove the stone. In more extreme cases, surgery may be required—though it's relatively painless, it can be uncomfortable to watch.
9. Gila Monster Saliva Reduces Appetite
Are you a chocoholic? Many people joke about their sweet cravings, but some truly struggle with food addiction. Chocolate, loaded with sugar and fat, triggers reward pathways in our brains, much like illegal drugs. Yale researchers conducted studies that reveal food addiction is remarkably similar to substance abuse.
While most of us aren't full-fledged food addicts, we’ve all likely experienced cravings or guilt after overindulging. But soon, there may be a novel way to curb those urges, thanks to a unique lizard found in the deserts of North America. The Gila monster is notorious for its venomous bite, but its saliva might just hold the key to ending food addiction.
Researchers from the University of Gothenburg in Sweden discovered that Gila monster saliva contains a compound known as exendin-4. Similar to a drug, this substance influences the brain's reward and motivation centers. Essentially, exendin-4 satisfies cravings without needing to consume any food. The effects were tested on lab rats, who are notorious snackers. After receiving exendin-4, they lost interest in food, even when offered their favorite treats like chocolate. Their appetite was completely suppressed.
In the future, scientists hope that people struggling with food cravings could take a pill containing lizard saliva to shed some weight. Exendin-4 offers another intriguing potential, as it also affects areas of the brain responsible for addiction to drugs and alcohol. This raises the possibility that Gila monster saliva could help treat those addictions as well. However, it leaves us wondering... who will be responsible for collecting the saliva from these creatures?
8. Spit Boosts Libido
Many students consider science to be dull, but that's only because they haven't encountered philematology—the scientific study of kissing. Philematologists spend their time analyzing the art of smooching, and with a good lab partner, it's probably quite fun. Kidding aside, kissing is an intriguing custom. More than 90% of human cultures practice kissing, and animals such as pygmy chimpanzees, bonobos, and even foxes and elephants engage in similar behavior. So, why is kissing so widespread?
Kissing triggers the release of dopamine, serotonin, and oxytocin, all of which play a key role in stirring up passion. But men also have a hidden agenda when it comes to kissing. According to Rutgers anthropologist Helen Fisher, men favor wetter kisses because their saliva contains small amounts of testosterone. Over time, this testosterone boosts a woman's libido, making her more inclined to engage in sexual activity. This is why men often initiate French kissing—they’re subconsciously attempting to set the stage for intimacy. As 'Crash' Davis wisely put it, 'I believe in long, slow, deep, soft, wet kisses that last three days.' That’s the secret.
7. Saliva Contains Natural Pain Relievers
Your mouth is quite a strange place. Not only does it host as many as 72 different types of bacteria, but it also produces one of the most powerful painkillers known to mankind. This painkiller is in your saliva and is called opiorphin, which is six times stronger than morphine.
Opiorphin works by protecting a chemical known as enkephalins. Essentially, enkephalins block pain signals from reaching the brain. When enkephalins break down, these signals race up the nervous system and trigger pain. Opiorphin prevents the breakdown of enkephalins, keeping the body from reacting to pain.
In experiments at the Pasteur Institute in Paris, researchers tested opiorphin's effectiveness by injecting rats with a painful chemical. After administering opiorphin, they observed that the rats stopped licking their painful paws. When rats were injected with either morphine or opiorphin, they were then made to walk across a bed of needles. The rats who received one milligram of opiorphin per kilogram of body weight felt no pain from the needles at all, while those who received morphine needed three milligrams to achieve the same result. That's a significant difference.
Although opiorphin is still undergoing tests, the results so far are promising. Not only is it more effective than morphine, but it doesn’t have the addictive side effects. Scientists also believe it might function as an antidepressant. If opiorphin lives up to expectations, it could change the face of modern medicine. And it would be quite ironic that humans have searched for ways to relieve pain for thousands of years, and all along, the solution was inside our mouths.
6. Cell Phones Can Make You Drool
If you ever encounter someone foaming at the mouth, try not to panic. Sure, they might have gone completely insane and be ready to attack, but it could also be that they’ve been chatting away on their cell phone for far too long.
Researchers at the Vidya Shikshan Prasarak Mandal’s Dental College and Research Centre in India (quite a mouthful, right?) discovered that people who use their phones frequently tend to drool more than those who don’t. In 2012, they split 142 participants into two groups: heavy phone users and a control group. The heavy users spent more than two hours a day talking on their phones, while the control group was a bit more conservative.
During the study, some researchers were tasked with measuring saliva production in the participants’ parotid glands. Located in both cheeks near the ears, these are the largest salivary glands in the body. The researchers noticed that the heavy phone users had parotid glands that were larger than average and experienced higher blood flow. Additionally, they were drooling like Old Yeller. Those heavy phone users produced 26% more saliva in the cheeks where they held their phones compared to the control group participants.
Of course, scientists emphasized that this correlation doesn’t necessarily imply cause and effect. However, they did suggest that electromagnetic radiation emitted by cell phones might be causing the parotid glands to swell up and produce a flood of saliva. So, you might want to clean your phone more often, or, better yet, maybe just stick to texting.
5. Introverts Salivate A Lot
There are two types of people in the world: extroverts and introverts. The two groups don’t typically mix, as introverts are usually preoccupied with finding a hiding spot. At the very least, introverts often struggle with conversations, and when they do engage, their brains respond quite dramatically.
The reticular activating system (RAS) is the part of the brain responsible for responding to social interactions. The theory suggests that introverts have a more active RAS than extroverts. In fact, scientists believe an introvert’s RAS is far more easily triggered than an extrovert’s. So when introverts interact with others, their RAS becomes overwhelmed. The only way to soothe it is to retreat from those unpleasant external triggers (i.e., other people).
But the RAS has another important function. Besides regulating social interactions, it also controls how much we salivate. Thanks to the RAS, researchers can tell if you’re an extrovert or an introvert by measuring how much saliva your mouth produces. All they need is a lemon.
In 1967, Professors H.J. and Sybil Eysenck from the University of London Institute of Psychiatry conducted a citrus-inspired experiment on 100 volunteers. They applied lemon juice to their volunteers’ tongues and observed as their mouths watered. While this reaction was expected from just about anyone, the Eysencks discovered that introverts salivated significantly more than extroverts. In fact, when the BBC did their own experiment, they found that shy participants produced 50% more saliva than their outgoing counterparts. This is due to an introvert’s RAS, which tends to overreact not just socially, but during salivation as well. Perhaps it’s a good thing that introverts prefer to keep their mouths shut most of the time.
4. Saliva Can Reveal Your Age
Being a criminal has become increasingly difficult in the era of advanced police technology. Criminals now have to be extra careful about every move they make, or risk getting caught. Thanks to researchers at UCLA, criminals have even more to worry about. It turns out, their own spit can be used to identify them.
The DNA in our saliva changes as we age. This process, known as methylation, activates certain genes while silencing others based on environmental influences like diet. Essentially, methylation alters how our genes express themselves as we get older. With this in mind, UCLA researchers studied the DNA of nearly 130 people. By focusing on two genes most affected by methylation, they were able to estimate a person’s age with a remarkable accuracy of within five years. That’s pretty impressive.
This discovery could greatly assist detectives in tracking down criminals, but it has important implications for doctors as well. Interestingly, a person’s biological age, which refers to the age of their DNA, doesn’t always align with their chronological age. (This is why scientists can only estimate a person’s age within a five-year range.) If doctors had access to someone’s biological age, they could make better decisions regarding medical treatments and more effectively manage age-related illnesses. This breakthrough benefits everyone, except for criminals who may now have to start bringing spit cups to crime scenes.
3. The Illegal Saliva Trade
Looking for something unusual but illegal? Well, you're in luck—there are plenty of criminals eager to make a deal. We've already learned about those involved in selling sperm, bear parts, and python skins, but South Africa is home to a particularly strange group of thieves who are literally 'drooling' to do business.
Tuberculosis is a serious health crisis in South Africa, with half a million new cases diagnosed every year. Unfortunately, issues like malnutrition and HIV are accelerating the spread of the disease. In an attempt to support TB patients, the government provides a monthly disability grant. However, this aid has attracted a new form of crime.
By late 2013, South Africa's unemployment rate had reached 24 percent. With so few opportunities, some people turned to fraudulent schemes. Hoping to exploit medical grants, healthy individuals sought out spit dealers—sly tuberculosis (TB) patients who would sneak into clinics and 'borrow' sputum sample bottles. These thieves would fill the containers with their own saliva and sell them for US$4.61 to US$9.21 (R50–100). The buyers then submitted the fake samples at clinics. It’s standard procedure to monitor people as they produce saliva, but with the high volume of patients, doctors often don't have the time. In their haste, they accept the fake bottles, run a few tests, and provide inaccurate results, ultimately granting the fraudsters a clean bill of health.
The illegal saliva trade may be gross, but it’s a thriving business for some. In 2009, one individual earned US$46 (R500) a month by selling spit on the streets. The competition is fierce, though, as tuberculosis is rampant in South Africa, and spit dealers can be found everywhere. After all, they carry their laboratories in their mouths.
2. Parents Have Super Spit
Pacifiers: a parent’s best friend or worst nightmare. While they’re excellent for soothing crying babies, pacifiers also become breeding grounds for germs, especially when they’re dropped on the floor. Most parents, upon finding their child’s pacifier covered in germs, will simply rinse it off with cold water. However, some parents opt for a less conventional method—they pick it up, pop it in their mouths, and suck off the dirt.
It may sound gross, but researchers at the University of Gothenburg suggest that parents who suck on their children's pacifiers might actually be helping protect them from allergies. In a study involving 65 babies, Swedish scientists compared kids whose parents washed their pacifiers with those whose parents licked them clean. Surprisingly, children whose pacifiers were cleaned with saliva were significantly less likely to develop eczema or asthma.
Scientists believe that by orally cleaning pacifiers, parents are transferring their own harmless bacteria to their babies. These seasoned microbes have fought off various infections and are experts in battling diseases. Once introduced into the baby’s microbiome (the community of microorganisms in the body), these bacteria help train the immune system, much like a drill sergeant preparing new recruits. They also teach the immune system to stay calm around common allergens, like cats and peanuts. So, while it may seem unsanitary, parents who suck on pacifiers are actually doing their children a big favor. Are any parents inspired by this?
1. Vampire Bat Saliva Might Help Treat Strokes
Many people, from reclusive billionaires to pet detectives, suffer from chiroptophobia: the fear of bats. Vampire bats are particularly despised, but this hatred might be misplaced. Yes, they drink blood, sometimes carry rabies, and look like creatures straight out of a nightmare, but their saliva could one day save your life.
Vampire bat saliva contains an enzyme called desmoteplase (DSPA). When these bloodsuckers feed on an unsuspecting victim, DSPA prevents the blood from clotting, allowing the bat to feast without interruption. But before you call in Van Helsing, keep in mind that while DSPA may sound unpleasant, scientists believe it could potentially be used to aid stroke patients.
In the United States, nearly 87 percent of strokes are ischemic strokes, which occur when blood clots block vessels in the brain, cutting off oxygen supply. Ischemic strokes can be life-threatening, causing paralysis, speech impairments, and even death. Treating these strokes is complex. Currently, doctors use a protein called tissue plasminogen activator (tPA) to dissolve the clots, but it must be administered within three hours of the stroke to avoid serious brain damage. Unfortunately, many patients miss this window and don’t receive tPA in time.
Enter vampire bat saliva. Researchers from Monash University in Australia conducted experiments on lab mice to compare the effects of DSPA with rt-PA, a recombinant version of tPA. They found that DSPA was not only more effective at breaking down blood clots but also much safer. The researchers determined that doctors could use DSPA up to nine hours after an ischemic stroke without risking brain damage. Though DSPA is still being tested, if it eventually becomes available, it will go by the name Draculin—certainly a nod to Bram Stoker's Dracula.
