Sneezing is a common, involuntary bodily reaction that carries a surprising amount of cultural significance and biological complexity, according to observations by writer Joe Bennett. While most people experience sneezing as the body’s way of expelling irritants from the nasal cavity, the phenomenon involves a range of surprising triggers and effects.

Globally, sneezing has attracted various interpretations. In Chinese tradition, for example, an unprompted sneeze is thought to indicate that someone is speaking about the person behind their back. However, the physical mechanics of sneezing remain the primary focus of scientific interest. For roughly one in three individuals, sneezing can be triggered by sudden exposure to bright light, a phenomenon that remains unexplained. Even more rarely, some people sneeze during sexual arousal. Researchers speculate this could be linked to the presence of erectile tissue in the nose or to similarities between the muscular tension and release involved in sneezing and orgasm.

The physical act of sneezing is marked by prominent involuntary movements: the closing of the eyes, a wrinkling of the nose, and a powerful expulsion of air. It was once believed that the heart briefly stops during a sneeze, putting the person momentarily closer to death, but this theory has been debunked. More importantly, attempts to suppress a sneeze — such as by pinching the nose — can cause injury due to the intense internal pressure generated during the event.

A sneeze expels a mixture of mucus and saliva as tiny droplets traveling at speeds of up to 160 kilometers per hour, potentially spreading germs as far as eight meters. This explains the importance of containment methods, including handkerchiefs and the professional practice known as the “vampire sneeze,” in which one sneezes into the crook of the elbow to reduce the spread of pathogens.

The widespread custom of saying “bless you” after a sneeze may have historical roots in responses to the bubonic plague, when sneezing was an early symptom, or stem from superstitions that sneezing expels the soul and invites evil spirits to enter if not protected by a blessing.

Bennett emphasizes that sneezing, like other bodily functions such as blinking and breathing, occurs beyond conscious control. Rather than serving as the “captain” of the body, human consciousness is more akin to a passive passenger, the writer suggests, as automatic physiological processes consistently operate independently of conscious will. Each sneeze serves as a reminder of the limits of conscious agency over the body.