The Reason We Sigh Isn't What You Think

The end of a long day, a frustrating task, or even thinking about something sad can often elicit a deep sigh of relief or anxiety. Making an audible sound when breathing out may feel like a much-needed release. But what exactly causes us to sigh, and could too much of it be dangerous?

Whether you realize it or not, you're probably doing a lot of sighing. Everyone does it, and fetuses have even been observed sighing in utero. It's a universal expression that's shared across languages and even displayed by individuals who are deaf. The average person will sigh about 288 times per day, and each sigh contains between two and five times the amount of air in a normal breath (via Current Biology). So is sighing good for anything other than showing our emotions?

Sighing is actually a natural physical response to the collapse of the alveoli in your lungs. When these tiny sacs spontaneously collapse, your lung function can decrease and prevent oxygen from getting to your brain and other parts of your body (via Healthline). By taking a deep breath and sighing, your body is working to fill up the alveoli and prevent damage to your organs. It not only feels good, but it's also literally saving your life.

When is a sigh not just a sigh?

So what happens when normal sighing turns into something else? According to psychologist Carolyn Fisher, Ph.D., frequent sighing can be a result of negative emotions like anxiety and fear (via Cleveland Clinic). The more you sigh, the worse that stress may become. This is because sighing can lead to hyperventilation, which in turn can make you even more stressed both physically and emotionally. Too much sighing is known as dyspnea. This hyperventilation syndrome can be used to identify people who suffer from PTSD and panic disorders. If you are sighing more than usual, you may be experiencing a side effect of anxiety, depression, excessive stress, or even a dangerous respiratory condition. 

If frequent sighing is causing you concern, it may be a sign that you should seek medical advice. But you're simply finishing up a tough assignment or just want to fully appreciate a beautiful day, fill up your lungs and let out a therapeutic "ahhh." Your body will thank you.