10 Facts About Your Tonsils

iStock/Neustockimages
iStock/Neustockimages

Most of us only become aware of our tonsils if they become swollen or infected. But these masses of lymphatic tissue in the mouth and throat are important immunological gatekeepers at the start of the airways and digestive tract, grabbing pathogens and warding off diseases before they reach the rest of your body. Here are some essential answers about these often-overlooked tissues—like what to do when your tonsils are swollen, and whether you should get your tonsils removed.

1. People actually have four kinds of tonsils.

The term tonsils usually refers to your palatine tonsils, the ones that can be seen at the back of your throat. But tonsillar tissue also includes the lingual tonsil (located in the base of the tongue), tubal tonsils, and the adenoid tonsil (often just called adenoids). "Collectively, these are referred to as Waldeyer's ring," says Raja Seethala, the director of head and neck pathology at the University of Pittsburgh Medical Center and a member of the College of American Pathologists Cancer Committee.

2. Tonsils are one of the body's first responders to pathogens.

The tonsils are a key barrier to inhaled or ingested pathogens that can cause infection or other harm, Seethala tells Mental Floss. "These pathogens bind to specialized immune cells in the lining—epithelium—to elicit an immune response in the lymphoid T and B cells of the tonsil," he says. Essentially, they help jumpstart your immune response.

3. Adenoid tonsils can obstruct breathing and cause facial deformities.

If the adenoid tonsils are swollen, they can block breathing and clog up your sinus drainage, which can cause sinus and ear infections. If adenoids are too big, it forces a person to breathe through their mouth. In children, frequent mouth breathing has the potential to cause facial deformities by stressing developing facial bones. "If the tonsils are too large and cause airway obstruction, snoring, or obstructive sleep apnea, then removal is important," says Donald Levine, an ear, nose, and throat specialist in Nyack, New York. Fortunately, the adenoids tend to get smaller naturally in adulthood.

4. As many of us know, sometimes tonsils are removed.

Even though your tonsils are part of your immune system, Levine tells Mental Floss, "when they become obstructive or chronically infected, then they need to be removed." The rest of your immune system steps in to handle further attacks by pathogens. Another reason to remove tonsils besides size, Levine says, is "chronic tonsillitis due to the failure of the immune system to remove residual bacteria from the tonsils, despite multiple antibiotic therapies."

5. Tonsillectomies have been performed for thousands of years ...

Tonsil removal is believed to have been a phenomenon for three millennia. The procedure is found in ancient Ayurvedic texts, says Seethala, "making it one of the older documented surgical procedures." But though the scientific understanding of the surgery has changed dramatically since then, "the benefits versus harm of tonsillectomy have been continually debated over the centuries," he says.

6. ... and they were probably quite painful.

The first known reported case of tonsillectomy surgery, according to a 2006 paper in Otorhinolaryngology, is by Cornélio Celsus, a Roman "encylopaediest" and dabbler in medicine, who authored a medical encyclopedia titled Of Medicine in the 1st century BCE. Thanks to his work, we can surmise that a tonsillectomy probably was an agonizing procedure for the patient: "Celsus applied a mixture of vinegar and milk in the surgical specimen to hemostasis [stanch bleeding] and also described his difficulty doing that due to lack of proper anesthesia."

7. Tonsil removal was performed for unlikely reasons.

The same paper reveals that among some of the more outlandish reasons for removing tonsils were conditions like "night enuresis (bed-wetting), convulsions, laryngeal stridor, hoarseness, chronic bronchitis, and asthma."

8. An early treatment for swollen tonsils included frog fat.

As early practitioners struggled to perfect techniques for removing tonsils effectively, another early physician, Aetius de Amida, recommended "ointment, oils, and corrosive formulas with frog fat to treat infections."

9. Modern tonsillectomy is much more sophisticated.

A common technique today for removing the tonsils, according to Levine, is a far cry from the painful early attempts. Under brief general anesthesia, Levine uses a process called coblation. "[It's] a kind of cold cautery, so there is almost no bleeding, less post operative pain, and quicker healing. You can return to normal activities 10 days later," Levine says.

10. Sexually-transmitted HPV can cause tonsil cancer.

The incidence of tonsillar cancers is increasing, according to Seethala. "Unlike other head and neck cancers, which are commonly associated with smoking and alcohol, tonsillar cancers are driven by high-risk human papillomavirus (HPV)," he says. "HPV-related tonsillar cancer can be considered sexually transmitted."

Why Can You Sometimes See Your Breath?

Chalabala/iStock via Getty Images
Chalabala/iStock via Getty Images

The human body is made up of about 60 percent water, meaning that when we breathe, we don’t just exhale carbon dioxide—we also exhale a certain amount of water vapor.

Water molecules need a lot of energy in order to remain in a gaseous form. When the warm water vapor molecules from your lungs reach colder air, they condense into “tiny droplets of liquid water and ice,” according to Wonderopolis. In fact, this process of condensation is also how clouds are formed.

But it’s actually relative humidity, not just temperature, that determines whether you can see your breath. The water vapor in your breath condenses into a liquid when it hits dew point—the temperature at which the air is saturated and can’t hold any more water in gas form. Since cold air can’t hold as much water vapor as warm air, you're much more likely to see your breath on a chilly day, but that's not always the case.

On more humid days, you may be able to see your breath even when it’s relatively warm outside. That’s because the air is already more saturated, making the dew point higher. And on especially dry days, even if it's cold outside, you may not be able to see your breath at all. Dry, unsaturated air can hold more water vapor, so you can huff and puff without seeing any evidence of it at all.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

7 Facts About Blood

Moussa81/iStock via Getty Images
Moussa81/iStock via Getty Images

Everyone knows that when you get cut, you bleed—a result of the constant movement of blood through our bodies. But do you know all of the functions the circulatory system actually performs? Here are some surprising facts about human blood—and a few cringe-worthy theories that preceded the modern scientific understanding of this vital fluid.

1. Doctors still use bloodletting and leeches to treat diseases.

Ancient peoples knew the circulatory system was important to overall health. That may be one reason for bloodletting, the practice of cutting people to “cure” everything from cancer to infections to mental illness. For the better part of two millennia, it persisted as one of the most common medical procedures.

Hippocrates believed that illness was caused by an imbalance of four “humors”—blood, phlegm, black bile, and yellow bile. For centuries, doctors believed balance could be restored by removing excess blood, often by bloodletting or leeches. It didn’t always go so well. George Washington, for example, died soon after his physician treated a sore throat with bloodletting and a series of other agonizing procedures.

By the mid-19th century, bloodletting was on its way out, but it hasn’t completely disappeared. Bloodletting is an effective treatment for some rare conditions like hemochromatosis, a hereditary condition causing your body to absorb too much iron.

Leeches have also made a comeback in medicine. We now know that leech saliva contains substances with anti-inflammatory, antibiotic, and anesthetic properties. It also contains hirudin, an enzyme that prevents clotting. It lets more oxygenated blood into the wound, reducing swelling and helping to rebuild tiny blood vessels so that it can heal faster. That’s why leeches are still sometimes used in treating certain circulatory diseases, arthritis, and skin grafting, and helps reattach fingers and toes. (Contrary to popular belief, even the blood-sucking variety of leech is not all that interested in human blood.)

2. Scientists didn't understand how blood circulation worked until the 17th century.

William Harvey, an English physician, is generally credited with discovering and demonstrating the mechanics of circulation, though his work developed out of the cumulative body of research on the subject over centuries.

The prevailing theory in Harvey’s time was that the lungs, not the heart, moved blood through the body. In part by dissecting living animals and studying their still-beating hearts, Harvey was able to describe how the heart pumped blood through the body and how blood returned to the heart. He also showed how valves in veins helped control the flow of blood through the body. Harvey was ridiculed by many of his contemporaries, but his theories were ultimately vindicated.

3. Blood types were discovered in the early 20th century.

Austrian physician Karl Landsteiner discovered different blood groups in 1901, after he noticed that blood mixed from people with different types would clot. His subsequent research classified types A, B and O. (Later research identified an additional type, AB). Blood types are differentiated by the kinds of antigens—molecules that provoke an immune system reaction—that attach to red blood cells.

People with Type A blood have only A antigens attached to their red cells but have B antigens in their plasma. In those with Type B blood, the location of the antigens is reversed. Type O blood has neither A nor B antigens on red cells, but both are present in the plasma. And finally, Type AB has both A and B antigens on red cells but neither in plasma. But wait, there’s more! When a third antigen, called the Rh factor, is present, the blood type is classified as positive. When Rh factor is absent, the blood type is negative.

Scientists still don’t understand why humans have different blood types, but knowing yours is important: Some people have life-threatening reactions if they receive a blood type during a transfusion that doesn’t “mix” with their own. Before researchers developed reliable ways to detect blood types, that tended to turn out badly for people receiving an incompatible human (or animal!) blood transfusion.

4. Blood makes up about 8 percent of our total body weight.

Adult bodies contain about 5 liters (5.3 quarts) of blood. An exception is pregnant women, whose bodies can produce about 50 percent more blood to nourish a fetus.)

Plasma, the liquid portion of blood, accounts for about 3 liters. It carries red and white blood cells and platelets, which deliver oxygen to our cells, fight disease, and repair damaged vessels. These cells are joined by electrolytes, antibodies, vitamins, proteins, and other nutrients required to maintain all the other cells in the body.

5. A healthy red blood cell lasts for roughly 120 days.

Red blood cells contain an important protein called hemoglobin that delivers oxygen to all the other cells in our bodies. It also carries carbon dioxide from those cells back to the lungs.

Red blood cells are produced in bone marrow, but not everyone produces healthy ones. People with sickle cell anemia, a hereditary condition, develop malformed red blood cells that get stuck in blood vessels. These blood cells last about 10 to 20 days, which leads to a chronic shortage of red blood cells, often causing to pain, infection, and organ damage.

6. Blood might play a role in treating Alzheimer's disease.

In 2014, research led by Stanford University scientists found that injecting the plasma of young mice into older mice improved memory and learning. Their findings follow years of experiments in which scientists surgically joined the circulatory systems of old and young mice to test whether young blood could reverse signs of aging. Those results showed rejuvenating effects of a particular blood protein on the organs of older mice.

The Stanford team’s findings that young blood had positive effects on mouse memory and learning sparked intense interest in whether it could eventually lead to new treatments for Alzheimer’s disease and other age-related conditions.

7. The sight of blood can make people faint.

For 3 to 4 percent of people, squeamishness associated with blood, injury, or invasive medical procedures like injections rises to the level of a true phobia called blood injury injection phobia (BII). And most sufferers share a common reaction: fainting.

Most phobias cause an increase in heart rate and blood pressure, and often muscle tension, shakes, and sweating: part of the body’s sympathetic nervous system’s “fight or flight” response. But sufferers of BII experience an added symptom. After initially increasing, their blood pressure and heart rate will abruptly drop.

This reaction is caused by the vagus nerve, which works to keep a steady heart rate, among other things. But the vagus nerve sometimes overdoes it, pushing blood pressure and heart rate too low. (You may have experienced this phenomenon if you’ve ever felt faint while hungry, dehydrated, startled, or standing up too fast.) For people with BII, the vasovagal response can happen at the mere sight or suggestion of blood, needles, or bodily injury, making even a routine medical or dental checkup cause for dread and embarrassment.

SECTIONS

arrow
LIVE SMARTER