When I sneeze, everyone hears it. The resulting shock waves shake windows, wake sleeping animals, and make nearby humans anxious. My partner, who sneezes like a vole hiccuping, insists that I sneeze on purpose. I argue that the decibel level is too loud to resist the urge to sneeze. Why would anyone sneeze so loudly?
What happens when you sneeze?
First, let’s be clear that sneezing is an important part of your body. “Your nose is the air filter for your lungs.” Tadashi Takashima“The nose is packed with epithelial cells (multipurpose cells found throughout the body), fine hairs, and thick mucus,” said Takashima, chief of the Otolaryngology and Head and Neck Surgery Department at Houston Methodist Academic Research Institute. These elements “trap particles and protect the lungs,” Takashima said. When particles accumulate, they need to be flushed out.
Also, Immune cells There are immune cells in the nose that are awakened when they detect high concentrations of compounds that induce sneezing. “Some of the chemicals produced as a result of the immune response cause changes in the nasal mucosa,” he says. Sheena CruikshankCruickshank, a professor of immunology at the University of Manchester, says the changes will be familiar to anyone who’s experienced a pollen-filled summer or a phlegm-heavy winter. Your body produces more mucus, your nose swells, and signals are sent to your brain via the trigeminal nerve, which gives sensation to the face. The signals are processed in an area at the base of the brain called the medulla oblongata, which triggers a reflex muscle contraction that results in a sneeze. But while there are many causes for sneezing, Cruickshank says there’s no reason for a virus to make you sneeze louder than grass pollen.
What causes a sneeze to be louder?
Rather, the key to determining how much of a sneeze you will produce lies in the structure of your respiratory system: The first step in the sneeze reflex is taking a deep breath, says Takashima.
“You need air to get it all out,” he adds. When air is drawn into the lungs, the vocal cords close tightly. When enough pressure is applied to the lungs, all the air is exhaled. “The blast of air pushing past the vocal cords creates the sneeze sound,” Takashima says. The shape and “slackness” of the vocal cords and other soft tissues at the back of the throat influence whether a sneeze is quiet or loud. Lung volume also determines how much air moves in and out of the chest during a sneeze, so no single physical measurement can predict the volume of a sneeze. “Even people with large lung volumes can have very small sneezes,” Takashima says.
The next time you sneeze and tear space-time apart, can you blame it on the resonating sound of your throat? Unfortunately, Takashima says it’s not that simple. “There are social norms and cultural factors that influence the sound of a sneeze,” he says.
How to Sneeze Quietly
Takashima points out that in Japan, the cultural emphasis on not bothering others allows people to suppress a sneeze. The key here, he says, is to minimize the amount of resonant energy flowing through the mouth — in other words, to keep your mouth closed. This reduces the amount of sneezing, he says.
Is the solution to this ear-splitting problem really that simple? A look at the medical literature reveals that stifling a sneeze may be a surprisingly bad idea. Case Study A report from a hospital in the Belgian city of Liège is a cautionary tale. At the peak of the COVID-19 pandemic, when loud sneezing in public was considered bad form, a 38-year-old man complained of facial pain and swelling after holding in a sneeze. A scan revealed he had fractured a sinus cavity. Takashima corroborates. “Holding in a sneeze can lead to medical problems, such as nosebleeds,” he says. “Air can get into the Eustachian tube, causing problems with the eardrum.”
But whether you feel dust particles tickling your throat in a library or your pet is sleeping comfortably nearby, there’s something you can do instead of letting out a loud sneeze. “There are times when you don’t want to make any noise or you want to be as quiet as possible,” Takashima says. “If you keep your mouth closed when you sneeze, it will definitely be quieter.”
