The human body can be an incredibly mysterious and complex system. Even the best physicians and researchers are presented with new challenges every day. However, these experts do know something that many of us take for granted: our bodies have natural barriers that protect us against organisms that can cause infection and improve our health. When looking at it this way, one might say that we were built to be our own superheroes. A healthy human body makes for a marvelous survival machine, one that works in our favor even before we are born. As fetuses, our defense system consists of toll-like receptors, or TLRs. These receptors operate like an alarm, alerting other immune cells to act against harmful ones, writes Dr. Michael Roizen, MD on Sharecare.com. Work is being done, whether or not we see it. Here are nine defense mechanisms and functions that your body is equipped with today.There’s a hypothesis that yawning may be a way for the brain to cool off, reports The New York Times. In one study involving 160 people, researchers found that people who spent more time outside in warm temperatures are less likely to yawn. Another study in 2007 revealed that using cold packs nearly eliminated contagious yawning. Who knew that this way of inhaling could be a thermoregulatory mechanism?

What starts as a tickling sensation in the nose and quickly turns into a violent expulsion is actually our body’s natural defense mechanism against germs and bacteria. The function of sneezing is to cleanse our nasal passages from irritants such as allergens and microbes.

Every morning when we wake up, we feel overpowered by a strong urge to stretch out our body. And apart from feeling so good and relaxing, it turns out that there are several benefits associated with the act itself. Stretching is shown to improve blood flow to our muscles, reducing stiffness and even improving our mood.

Hiccups mainly occur due to a sudden disturbance in the nerve pathways connecting our brain and diaphragm. Usual causes of hiccups include eating too quickly, too much and swallowing large bits of food at once. And even though they can be extremely annoying, they remind us to eat slowly, a practice which can help improve digestion.

Imagine going off to sleep and getting a sudden sensation that you’re falling off a cliff, causing your arms and legs to jerk. This is called a hypnic jerk. Hypnic jerks are a type of myoclonic twitch that occurs when breathing and pulse rates suddenly slow down, signaling our brain to think that the body might be in danger. In an attempt to save you, it gives you a mild shock, just enough to wake you up. It might not save you from actually dying—you’ll soon find that you were in no real danger—but it will save you from a bad nightmare. If you’re looking for a more restful sleep, Dr. William Kohler of the Florida Sleep Institute recommends avoiding caffeine, food and smoking shortly before bedtime.

One study involving a test of 20 subjects revealed that wrinkly fingers allowed for better grip. Another study, however, proved that wrinkles had nothing to do with dexterity. Still, there are many other unsightly characteristics we can find on our body that benefit us. These include sweat and earwax. When you sweat, your pores open up and release extra buildup. Even though most of us want to get rid of earwax, having a right amount is important. Earwax helps prevent bacteria, dust, and other germs from entering your ears.

Tears are among the several defense mechanisms that protect our eyes from infection. They flush foreign particles from the surface and transport antimicrobial agents to the area to work in our defense. They also help reduce stress hormones, which is why some experts encourage their patients to cry.

Animals with a thick hair coat have a few benefits from goosebumps. This is because the contraction causes the hair to stand up and serve as insulation when the body feels cold. The hair can also make them appear bigger to potential threats. Goosebumps, or the pilomotor reflex, are caused by adrenaline or a sudden change of temperature. Strong emotions are also a common cause in humans. Although we don’t have the same benefits from goosebumps that other animals do (unless you live in the wild and have ridiculously hairy arms), they still help us feel things that we probably wouldn’t be able to detect with our skin alone, such as tiny bugs.

Your brain is packed with defense mechanisms, which can sometimes prevent you from positivity and productivity. When receiving feedback, especially harsh feedback, your brain might perceive the news as purely good or purely bad. Try to steer away from thinking in black and whites. Instead of seeing an “area of improvement” conversation at work as catastrophic, try to view it as an opportunity. Yes, we know it’s easier said than done, which is why it’s important to practice.
