It’s certainly possible to die while laughing — probably by choking on something. But I was unable to find any documented evidence of someone literally “laughing to death.”
In fact, recent research suggests laughing is actually very good for you. According to the Indiana University School of Medicine, laughing helps relax tense muscles, lowers blood pressure, and even burns calories. Humor and laughter is also becoming increasingly popular as a form of psychiatric therapy. Look out, Carrot Top.
Cardiologists at the University of Maryland Medical Center found that people with heart disease are 40% less likely to laugh in a given situation than people without heart disease. The key here seems to be stress reduction; stress impairs the production of endothelial cells, which form a protective lining in our blood vessels. A weak endothelium can lead to hardened arteries and, quite literally, a hardened heart.
What exactly is laughter? As HowStuffWorks explains, laughter is a physiological response that’s triggered by the limbic system, or the part of the brain that governs motivation and emotional behaviors. During laughter, the epiglottis constricts the larynx, restricting our ability to breathe. That’s why a really good joke can sometimes seem pretty dangerous — but thankfully the breathing instinct always wins in the end.