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Everyday Mysteries: Fun Science Facts from the Library of Congress

Why does pepper make you sneeze?

Because the chemical piperine, an irritant, gets into the nose.

A sneeze is a reflex that is triggered when nerve endings inside the mucous membrane of the nose are stimulated.

Pepper, be it white, black, or green, contains an alkaloid of pyridine called piperine. Piperine acts as an irritant if it gets into the nose. It stimulates (or irritates) the nerve endings inside the mucous membrane. This stimulation will cause you to sneeze. Actually, the nose wants to kick out this irritant and the only way it knows how to do this is by sneezing."

Did you know ...

Sneezing is called sternutation.
When you sneeze air rushes out your nose at a rate of 100 miles per hour!
There are an estimated 5 million scent receptors in the human nose.
Our noses produce an estimated one to two pints of mucus a day.

Pepper facts:

Known as the "king of spices" because it is one of the oldest and most popular spices in the world.
Pepper was so valuable that in ancient Greece and Rome it was used as currency.
It is believed that when the Goths defeated Rome in 410, they demanded a ransom of 3,000 pounds of pepper, along with other valuables such as silk.
During the middle ages, peppercorns were accepted in lieu of money for dowries, rent and taxes.
During the 19th century, Salem, Massachusetts played an important role in the world pepper trade and made some of America's first millionaires.

Related Web Sites

Science Update and Why Is It? Archives - From the American Association for the Advancement of Sciences. To listen to a radio broadcast of why pepper makes you sneeze Click on link that reads “Why is it: Pepper sneeze?” (Broadcast aired on June 3, 1999).
Piperine Homepage - Created by Lindsey Wakely. This Web site provides information about the history, chemical properties, and uses of piperine. Also included is a reference page.
HerbMed® - HerbMed® is an herbal database that links to data on the scientific uses of herbs in medicine. Listed in the entry for piper nigrum are links to clinical trials, scientific papers, and cultivation information.
Gernot Katzer's Spice Dictionary - The entry for piper nigrum includes information on the etymology and origin of black pepper. Also includes translation of pepper in many different languages and selected links for more information.
Rhodium: Chemistry and Pharmacology Links -The page discusses the piperine and chemical content found in pepper. Includes links to papers on the topic.