Capsaicin: The Incendiary Ingredient in Hot Peppers

What makes a hot pepper hot?

The incendiary ingredient, called capsaicin, is a powerful organic chemical that torches the tongue and irritates nerve endings in the mouth and nose. Capsaicin is highly concentrated in a pepper’s central membrane, which holds the seeds. Despite a burning taste, hot peppers can help cool the body by fostering perspiration.

The family of capsicum peppers is usually divided into sweet (bell) and hot (such as cayenne, chili or Tabasco). These are not to be confused with black or white pepper, which are condiments obtained from the dried fruits of East Indian vine plants. The peppers are close relatives of the eggplant, Irish potato and tomato. Archeologists have found evidence of capsicum pepper seeds at Tehuacan, Mexico, dated before 5000 B.C.

Although hot peppers can reduce even the most avid pepper enthusiast to a wheezing, eye-watering mess, they generally cause no harm to the stomach, according to Arnold G. Levy, a Silver Spring, Md., gastroenterologist.

The exceptions are red chili peppers and spicy Indian curry. Curry powder is prepared from turmeric and other spices such as coriander, cumin and cayenne pepper. “We have scientifically documented that these two foods can cause gastritis, but we don’t know why,” says Levy.

Some experts speculate that capsaicin stimulates production of acid in the stomach and therefore causes indigestion. Of course, too much of anything can be harmful. Capsaicin is a chemical irritant to the body in extremely high doses, says Antone R. Opekun, a physician’s assistant at Baylor College of Medicine.

Whether hot peppers are whole or ground up in sauces, Americans enjoy their piquancy. From 1984 to 1988, Americans consumed about 155 million pounds of hot spices, which include hot peppers, according to the American Spice Trade Assn.