What Are Sighs and Why Do They Occur?

Although it seems that we only sigh for love, nostalgia, or relief, in reality, there are several reasons to do so, that go beyond the emotional.

Written and verified by the psychologist Esther Rodriguez.

Last update: 21 December, 2022

Gustavo Adolfo Bécquer once wrote: “Sighs are air and go to the air. Tears are water and go to the sea. Tell me, woman, when love is forgotten, do you know where it goes?”. Nevertheless, he didn’t give us an explanation of what a sigh is.

If we look for the verb ‘to sigh’, the first definition that appears in the Oxford English Dictionary is “emit a long, deep audible breath expressing sadness, relief, tiredness, or similar”. The literary meaning is “to f eel a deep yearning for (someone or something lost, unattainable, or distant)”.

These conceptualizations give an emotional component to the act of sighing. However, it’s worth addressing the question of this article from both a physiological and an emotional point of view.  

The sigh from the biological approach

The respiratory system is one of the main engines of the body. Without it, we couldn’t live, since it regulates our heart rate and our sleep.

We breathe more or less 16 times per minute. However, every so often an extra breath occurs. This means that the pulmonary alveoli detach from the lungs so that the entire lung can breathe correctly. This ‘brief pause’ is the sigh we’re talking about, a deep aspiration that’s followed by a prolonged expiration, whose main function is to oxygenate the blood well.

If we didn’t sigh, our bodies would collapse. That’s because it’s only with a sigh that our lungs receive the necessary oxygen to release the accumulated carbon dioxide that couldn’t come out in a normal breath.

Adequate functioning of the respiratory system guarantees us greater internal defenses. Furthermore, it often favors the reduction of anxiety due to the drop in cortisol. Therefore, we always sigh.

As a matter of fact, we need to sigh to stay alive. Therefore, the sigh is a normal mechanism that even happens when we’re sleeping.

The sigh from the psychological approach

As we pointed out at the beginning, most definitions point to the emotional component of the term, sigh. This is why most of us associate it with boredom, tiredness, anger, love, etc. Indeed, we can’t deny that there’s a close relationship between our breathing and our mood.  

Relief and anguish, two common faces of the sigh

As Chiozza (2008) pointed out, a sigh doesn’t have to indicate a painful situation, because sometimes we sigh for positive reasons. In these cases, it’s as if the sigh were a greeting with which we bid farewell to our past anguish. Since it comes from a moment of suspension of breath, it has a ‘let off steam’ connotation that expresses the overcoming of discouragement. Perhaps something internal that’s ready to come out.

However, the sigh, in addition to being a necessary biological phenomenon , can also act as a symptom that warns us that something isn’t right. It might express a truth that we don’t know or we’re choosing to ignore or deny, perhaps because we’re not yet ready to manage it.

In fact, a sigh could be considered as an encrypted message that we need to decipher. It’s our body speaking when unresolved or unverbalized emotional conflicts appear, either due to internal or environmental difficulties.

Therefore, the function of a sigh in relation to a family conflict, for example, should be observed. Because it could be a warning sign that there’s a problem to solve.

Finally, both from the biological and psychological approach, the action of sighing helps us to stay alive. It gives us a brief pause so that our bodies can continue their correct functioning and be able to redirect certain experiences, if any, that are provoking internal emotional conflicts.