All human beings with normal psycho-physiological functioning (within the average) will have cried and will do so multiple times throughout their lives. In fact, when a baby is born it is the first thing expected of him/her and the first sign that his/her organism is functioning correctly.

We all know that crying is natural and that it happens when our eyes are itchy or when we are sad , but next we are going to ask ourselves what mechanisms and what usefulness lies behind this.

Types of tears…

First of all, we must differentiate between physiological tears and emotional or psychological tears .

Physiological tears

The physiological tears are those that serve to protect our visual system (the eyes), there are reflexes and lubricants .

The lubricating tears are those that originate in the cornea, clean and protect the eye from external environmental agents (dust, batteries etc.). Each day, a quantity of lubricating tears of approximately 1 ml is produced. The reflex tears are those that protect against external attacks such as gas or irritating chemicals, they are those that appear when peeling an onion for example, they contain a large amount of antibodies that will protect the eye from bacterial attacks.

Emotional tears

Finally we have the emotional tears , which we are going to focus on.

These appear before a strong emotion, the hypothalamus intervenes in the emotional interpretation and it is the one who sends the orders to the ocular organs for the fabrication of tears. According to a study (Walter & Chip, 2006) with a sample of more than 300 people, on average men cry emotional tears once a month and women at least five times a month , the difference between the two sexes is explained by hormonal variations during menstruation.

Why do we cry when something moves us?

And what is the use of producing tears in a situation of emotional intensity? Usually they occur in a painful situation, in this case secreting tears seems to have an analogous and palliative function of pain .

As demonstrated by William H. Frey, a biochemist at St. Paul-Ramsey Medical Center in Minnesota, the emotional tears we shed in the face of our own or someone else’s dramatic situation carry with them out of the body a good dose of potassium and manganese chloride, endorphins, prolactin, adenocorticotropin and leucine-encephaline (a natural painkiller).

The brain when we cry

In addition, when the brain cries it wears out a large amount of glucose and when it finishes doing so we feel tired and more relaxed as if we had done sport, which can help the body rest in stressful situations. In addition, the mere fact of crying will make us withdraw into ourselves, introspect and will allow us to cover the need to listen and take care of ourselves for a few moments, leaving aside the other external things that concern us in our daily lives.

The social function of crying

Of course, shedding tears has a very important adaptive social function , when we see others crying we know they may need help or different treatment than usual.

Thus, if we add biological function to intrapersonal and relational function, shedding tears after a loss for example, will help us to go through the emotion in a better way.

And why do we sometimes cry when we’re happy?

When we experience an emotion of extreme joy, our body sometimes interprets it as “excessive” and our emotional system as a loss of control , in these circumstances, crying helps to restore emotional balance.

What if I can’t cry when I’m sad?

Some people suffer from an autoimmune disease, Sjören’s Syndrome, in which there is a permanent dryness in the tear .

But leaving aside possible physiological problems with tear production, some people have trouble crying when they have a loss or strong emotion, usually accompanied by an inability to feel sad. This can be the result of multiple causes and on many occasions has to do with a bad experience of emotional management at a certain moment (for example having suffered a severe depression or having a person close to you who suffers from it), through which an irrational fear of crying is triggered.

Social norms also influence certain cultures where crying is “frowned upon”. In many cultures, something as natural and innate as crying is “repressed” and it is important to relearn to cry when necessary, because as we have commented above, it has multiple advantages for our emotional health.

Bibliographic references:

  • Baños Díez, March Pujol. Ocular pharmacology. Univ. Politèc. de Catalunya; 2004
  • Walter, Chip. Why do we cry?. Scientific American Mind. 2006 Dec; 17(6):44.
  • William H. Frey, Muriel Langseth. Crying: The Mystery of Tears. Minneapolis: Winston Press; 1985.