The Rumor: Sighing means you’re sad or upset
Remember in Casablanca when Ingrid Bergman said, “Play it, Sam,” and we got: “You must remember this. A kiss is just a kiss. A sigh is just a sigh…”? It’s a great cinematic moment that shows how common it is to let loose great big sighs when we’re sad, frustrated or regretful (as Ilsa and Rick were in the movie). Sighing is little more than a way to physically express negative emotions. Right?
The Verdict: We sigh for a variety of reasons – and they’re not all emotional
Turns out, sighing serves a more complex purpose than just simple emotional expression — and not all sighs are created equal. While it’s true that we often sigh when we’re unhappy or stressed out, we also do it when we’re feeling wistful, bored, relieved or even melted by love (as Pepé Le Pew does in those Warner Bros. cartoons). Sometimes I sigh when I’m just plain worn out. “Sighing is like a paralanguage,” says Jordan Gaines Lewis, a neuroscientist at the Pennsylvania State College of Medicine. “You’re subconsciously letting those around you know if you’re tired, or frustrated, or relieved… But [studies] have shown that when we hear someone else sighing, we always think it’s negative.”
Lewis says that we rarely sigh for just one reason, because of how our bodies and emotions are connected. Breathing in particular is such a sensitive process that sighing is vital to keeping it in sync. As University of Leuven researchers discovered, breathing patterns change depending on how much oxygen the body needs; stress, anxiety and excitement can throw them out of whack. At times like these, sighing forces more air into the lungs and resets the pattern. (The more off-balance your breathing, the noisier your sigh will be.)
The researchers also found that breathing in the same state for too long can cause the lungs to stiffen and exchange oxygen and carbon dioxide less efficiently. So your body will occasionally throw in a good long sigh to loosen the lungs’ air sacs and relieve the diaphragm and other respiratory muscles. This is why sighing can create such an immense sense of relief that you feel it emotionally as well as physically.
A sigh can also serve as a mental reset button of sorts. Lewis cites a study in which researchers frustrated participants by giving them impossible mental puzzles, then counted how often they sighed in response. “They would sigh a lot more, then keep trying…,” he says. “The interesting thing is that they didn’t even know that they were sighing. They weren’t aware of it.” When we get into a mental knot, then, sighing can be like hitting Ctrl+Alt+Del — it reboots our minds.
Like yawning, sighing happens subconsciously. We can’t intentionally sigh — that’s really just taking a deep breath, and doing that too often can be bad for you. Too many forced sighs can make you hyperventilate. In extreme cases, it can even trigger a panic attack.
The moral of the story? Let your body decide when it needs to sigh. If you want to “sigh” on purpose, do in moderation — i.e., only during those times when you really, really want to hit reset. And we all have times like those. Sigh.