Tag Archives: physiology

Why Do We Sneeze?

What’s the scoop?

Long before the sneezing panda wowed us all, sneezing has been an integral part of our lives. It has found a special place in our culture, from the cliche pepper under your nostrils to induce it, to the myth that if you sneeze with your eyes open they will fly out of their sockets, or to the popular description of sneezing feeling like 1/10 of an orgasm. Like coughing, yawning, and excreting waste, it is an every day bodily function that everyone does, but not many take a lot of time to think about.

So what’s the point of sneezing? Why do we and all these other animals do it? How do we even sneeze? Why does it feel so good? Why don’t we stop asking questions and start answering them?

Warning! Scientific Content:

To get to the bottom of this, we should first understand what a sneeze is and what our bodies are doing when we sneeze. The non-scientific dictionary.com defines sneezing as emitting air or breath suddenly, forcibly, and audibly through the nose and mouth by involuntary, spasmodic action. I think we already knew that.

So let’s dive right into the anatomy and physiology. As we breath air into our nostrils, the passageway becomes narrower and narrower. This narrowing increases the air’s turbulence and in turn increases the amount of interaction between the air and the lining of the nose, called the nasal mucosa. This allows for both the exchange of heat and moisture as well as clearing the inhaled air of foreign particles, which can irritate the respiratory epithelium. Besides foreign particles like dust, pollen, or other allergens, irritation can be triggered by viral infections (a cold or flu), cold air, pollution, and even the sun or a large meal.


When this occurs, a response takes place. First, chemicals like histamine (as in antihistamine, a popular remedy for allergy symptoms) or leukotriene are released. These chemicals irritate the nerve cells in the nose, which activate a reflex in the brain. The brain sends a signal to activate the muscles in your pharynx (throat) and larynx (voice box), creating a large opening in the nasal and oral cavities and allowing for a rapid expulsion of air and some noise, a sneeze.

The soft palate and uvula depress while the back of the tongue elevates to partially close the passage to the mouth so that air ejected from the lungs may be expelled through the nose. The high velocity of the airflow is achieved by the buildup of pressure inside the chest with the vocal chords closed. Sudden opening of the cords allows the pressurized air to flow back up the respiratory tract to expel the irritants.

Here I would like to point out that your heart does not stop during a sneeze. That is a common misconception which is absolutely false. You are very much alive throughout a sneeze.

Wait, what’s the point of sneezing?

Put simply, we sneeze to expel foreign particles that we breath in from the air, stuff like germs that may be harmful to us.

Evolutionarily speaking, this is highly advantageous. Those that sneeze can quickly rid their bodies of harmful bacteria or pollutants, leading to a healthier and longer life. They would also spread more airborne germs, and non-sneezing animals would have a tougher time ridding themselves of them. Selection would therefore favor sneezing animals over non-sneezing animals, and sneezing animals would proliferate.

So, why does it feel so good?

Though not all of us agree with the phrase, I’m sure each of us has heard a sneeze being described as “1/10 of an orgasm.” In researching the answer to this question, my favorite explanation was that “semen and sneezes both have mucus in them, so they both feel good.” While it is true that they have these two things in common, mucus does not simply equate to pleasure. But, the person was on to something. To answer the question we can look at the many qualities that a sneeze and an orgasm share:

1.) Endorphins. These little neurotransmitters are produced in the brain and pituitary gland during an orgasm, as you exercise, while eating spicy food, and, oh yeah, as you sneeze! They closely resemble opiates (think painkillers like morphine) by procuring a sense well-being.

2.) Pressure and Release. In both cases, we build up a kind of tension within our bodies and forcibly alleviate it. In a way, it’s like having a really fast massage or a quick but effective hug.

3.) Stretch. This explanation might be a bit of a stretch, but in both cases we stretch some muscles that we wouldn’t normally use consistently. Again, we are alleviating tension and the buildup of stiffness due to a large protein called titin.

So there you have it. I leave you with the words of Sarah Silverman: “Some say sneezing is like having an orgasm… But still, don’t sneeze on my boobs.”