The human body is a complex structure that can be difficult to fully understand. The body comprises various biological cycles and systems, and self-defense mechanisms are just one such system.
Self defense mechanisms are physiological and psychological strategies that are brought by the unconscious mind as a natural survival skill.
These mechanisms protect us from physical harm and help us lead a healthy life.
Here are 10 fascinating things your body does in self-defense.
Although it can cause discomfort, fever is another nonspecific defense mechanism of the body in response to numerous traumas. It causes a modest rise in body temperature to reduce the replication of viruses and other pathogens. It is usually caused by an infection like the flu or a urinary tract infection.
When the viruses and bacteria invade the body and cause injury to the tissues, the immune system responds by producing several circulating substances called pyrogens.
These chemicals affect the brain’s hypothalamus that regulates body temperature. They alter the temperature sensors and trick them into thinking that the body is cooler than normal. In response, the hypothalamus raises the body’s temperature and you get a fever.
A fever with an unknown underlying cause or that lasts longer than a few days should be thoroughly checked by a doctor to rule out the possibility of a serious medical condition like HIV and some cancers.
When suffering from a cut or wound, your skin becomes vulnerable to attack by bacteria and other micro-organisms that can enter through the wound. To protect against infection by the pathogens, your body develops a scab in order to quickly close the wound.
Basically, a scab is a mesh of fibrin protein in which platelets are stuck. Platelets are tiny structure in blood that aid in wound healing.
A 2008 study published in the journal Frontiers in Bioscience notes that platelets aggregate and form a procoagulant surface favoring thrombin generation and fibrin formation to prevent blood loss at the site of injury.
Platelets also help combat bacteria and contribute to protection against infection.
Gradually, as the wound heals, tissue regeneration pushes out the scab which eventually falls off.
Sneezing is another natural mechanism that the human body does in self-defense.
Normally, one sneezes when the nasal passages fill up with too many allergens, microbes, dust, animal dander or other irritants. Through sneezing, the body gets rid of them.
Sneezing is a common symptom of colds and chronic allergies. Some people even sneeze when they eat a really big meal or when they’re exposed to sunlight.
The process of sneezing is very powerful. The air from a human sneeze can travel at speeds of 100 miles per hour or more. This can spread germs a long distance and is the reason why experts recommend covering your nose and mouth when you sneeze.
The powerful force also causes the eyes to involuntarily close to protect them from microorganisms and particles spewed out from a sneeze.
Hiccups are an involuntary action that almost everyone experiences in their lifetime. It is also considered a self-defense mechanism.
Eating very fast, swallowing large pieces of food or overeating can lead to hiccups. This is because such acts can irritate the pneumogastric nerve, which is closely linked to the stomach and diaphragm. A bout of hiccups works as a natural mechanism to protect your diaphragm and stomach.
A 2012 study published in Insights & Perspectives reports that hiccups are triggered by the presence of air in the stomach in infants. For adults, hiccups reflect a persistence of an infantile reflex and a reminder that we may have eaten too quickly.
5. “Pruney” Fingers
Surprisingly, even the wrinkles that appear on the skin of your hands or those pruney fingers also play an important role in your body’s self-defense toolkit.
When the body comes in with an increased amount of moisture, the brain understands that the environment might be slippery. This leads to change in the skin on your hands, making it winkled.
Wrinkled fingers can better grip smooth surfaces, causing less accidents and falls.
A 2011 study published in Brain, Behavior and Evolution reports that wrinkled fingers and toes have a better grip on wet objects.
Another study published in 2013 in Biology Letters theorized that wrinkled fingers and toes might have helped our ancestors handle tools in rainy conditions or have steadier footing in wet conditions, providing an advantage over others animals.
6. Blinking Eyes
Blinking may not seem to be that helpful but it is vital to your overall health. It provides your eyes with necessary fresh moisture that protects your eyes from being strained and irritated.
In fact, when you blink, your eyes get covered with a layer of tears (which is filled with protein and moisture), water (that washes dirt and debris out of your eyes), and an outer layer which contains an oily substance that lubricates your eyes and prevents chafing on your eyes.
Not blinking enough can lead to dry, sore, irritated eyes and blurry vision. Moreover, it can cause eye strain and potentially damage to your eyes.
Goosebumps or shivers down the spine arise in different situations, but they are also a part of self-defense.
Goosebumps mainly appear to reduce the amount of heat the body loses through the pores of the skin. This helps keep the body warm in inhospitable climatic conditions.
However, you may also get goosebumps during stressful moments or when feeling intense emotions.
Goosebumps occur due to the contraction of arrector pili muscles located around the hairs in the dermis of the skin. The brain understands danger and it affects the hypothalamus, the section of the brain that controls certain nervous system functions.
The same kind of reaction occurs when you feel intense emotions, such as love, happiness or shock.
Yawning mostly occurs before and after sleep, during tedious activities and as a result of its contagious quality. It is often related to tiredness, stress, sleepiness, boredom and hunger.
However, according to research, the main purpose of yawning is to cool down the brain.
When you yawn, powerful stretching of the jaw occurs that leads to increased blood flow in the neck, face and head. Also, a deep intake of breath forces a downward flow of spinal fluid and blood from the brain. The cool air that you take into the mouth cools down these fluids.
A 2013 study published in the International Journal of Applied Basic Medical Research suggests that yawning may help cool the temperature of the brain.
One year later, another study published in Physiology & Behavior also reported that as per the thermoregulatory theory, yawning aids in brain cooling. Yawning is constrained to an optimal thermal zone of ambient temperature.
Inflammation is another defense mechanism which the body adopts to protect against infection and injury. When it lasts only for a few days, the condition is called acute inflammation and when it lasts longer then it is called chronic inflammation.
In case of acute inflammation, the discomfort usually disappears as soon as the inflammatory response has done its job. Some of the common examples of acute inflammation are problems like sore throat, insect bites, bee stings, etc.
The inflammation, however, may prove to be harmful if the regulatory mechanisms of the inflammatory response are defective.
Also, there can be prolonged or damaging inflammatory response due to inappropriate immune response as in cases of allergic, hypersensitive and autoimmune reactions characterized by chronic inflammation.
10. Memory Loss
Memory loss is a natural defense mechanism that helps protect against psychological damage after an emotional or psychological trauma.
Sexual abuse, violence, natural disasters, and other traumatic events can be followed by dissociative amnesia that causes disruption of memory, awareness, consciousness, identity, and/or perception.
Thus, the loss of memory allows you to cope by allowing you to temporarily forget the details of a traumatic event. The memories, however, are still deeply buried in the mind but cannot be recalled.