Why do we Cry?

Shedding tears is a universal experience, whether triggered by a heart-wrenching movie, a heartwarming reunion, or a clumsy encounter with a coffee table. But have you ever wondered why we have evolved to cry?

One theory suggests that this emotional response dates back to our prehistoric ancestors, when tears streaming down their eyes served as a signal of surrender, indicating that they posed no threat to their aggressors.

As we fast forward to today, scientific research reveals various biological explanations for shedding tears. Reflex tears, for instance, are triggered by the irritation caused by smoke or Sulphenic acid from onions. When this occurs, sensory nerves in the cornea send a message to the brain signaling the need for eye protection. Subsequently, the brain releases hormones to the lacrimal glands behind the eyelid, prompting the production of tears to shield the eyes and dilute the irritant.

Crying usually takes the form of emotional outbursts. When intense emotions overwhelm you, your brain's cerebrum recognizes that you're experiencing a powerful emotional response to something. In response, the endocrine system releases a series of hormones that trigger the lacrimal glands to produce tears that flow down your cheeks.

It has been discovered through research that tears serve a biochemical purpose when it comes to emotional crying. While reflex tears are primarily composed of water, emotional tears contain various chemicals such as adrenocorticotropic hormones, which are present during stressful situations, and leucine-enkephalin, an endorphin that alleviates pain and enhances one's mood. Hence, crying seems to be a natural mechanism for releasing accumulated hormones and toxins during moments of intense emotions.

Battle of Sexes

It's commonly believed that women cry more than men, but there's actually scientific reasoning behind it. Research indicates that women cry four times as often as men, with both cultural and biological factors playing a role.

Until puberty, boys and girls cry at similar rates. However, as boys' testosterone levels increase, they tend to express anger rather than sadness. On the other hand, girls experience a surge in estrogen levels, affecting endorphin production and leading to more emotional reactions.

As men and women age, their hormone levels tend to balance out, resulting in a more equal tendency to cry across genders.

Purpose of Crying

Did you know that tears are not just a result of emotions? Our eyes produce three types of tears, each serving a different purpose. The first type, basal tears, are always present to prevent our eyes from drying out. On average, our bodies produce 5 to 10 ounces of basal tears every day. These tears drain through our nasal cavity, which explains why we often end up with runny noses after a good cry.

Reflex tears, the second type, are essential for safeguarding the human eye from harsh irritants such as smoke, onions, or strong dusty winds. When the sensory nerves in the cornea detect these irritants, they send a message to the brain stem. The brain stem then triggers the glands in the eyelids to release hormones, prompting the eyes to produce tears that effectively remove the irritant.

Emotional tears, the third type of tears, originate from the cerebrum where feelings of sadness are processed. This prompts the endocrine system to release hormones that reach the ocular area, resulting in the formation of tears. These tears are often shed by individuals who witness the heart-wrenching demise of Bambi's mother or experience personal losses.

To Sympathize

Did you know that sympathy cry is a real phenomenon? Just like how your tears can elicit concern and support from others, you might find yourself feeling sympathy when you witness someone else's tears or emotional distress. It doesn't even matter if that person is real or fictional, as a study from 2016 found that sympathy crying can occur in response to emotional movies. Crying in response to someone else's pain is actually a positive thing, as it shows that you have the ability to consider different perspectives and imagine yourself in someone else's shoes. In essence, it means that you possess a great deal of empathy.