What makes chiles hot

Why would anyone willingly eat something that causes pain? Capsaicin triggers a rush of stress hormones. These will make the skin redden and sweat. It can also make someone feel jittery or energized. Some people enjoy this feeling. But there is another reason why chilies show up on dinner plates the world over.

Hot peppers actually make food safer to eat. Before refrigerators, people living in most hot parts of the world developed a taste for spicy foods. Examples include hot Indian curries and fiery Mexican tamales. This preference emerged over time.

The people who first added hot peppers to their recipes probably had no idea chilies could make their food safer; they just liked the stuff. But people who ate the spicy food tended to get sick less often. In time, these people would be more likely to raise healthy families.

This led to populations of hot-spice lovers. People who came from cold parts of the world tended to stick with blander recipes. The heat of a chili pepper is not actually a taste. When it does, it alerts the brain. The brain then responds by sending a jolt of pain back to the affected part of the body. If a person accidentally places fingers on a hot stove, the pain makes him or her yank that hand back quickly.

The result: a minor burn, not permanent skin damage. People, mice and other mammals feel the burn when they eat peppers. Birds do not. Why would peppers develop a way to keep mammals away but attract birds?

Mammals have teeth that smash seeds, destroying them. Birds swallow pepper seeds whole. Later, when birds poop, the intact seeds land in a new place.

That lets the plant spread. Those with pepper allergies or stomach conditions do need to stay away from chilies. But most people can safely eat hot peppers. Capsaicin does not actually damage the body in the same way that a hot stovetop will — at least not in small amounts. In fact, the chemical can be used as a medicine to help relieve pain.

It may seem bizarre that what causes pain might also make pain go away. The human body is good at repairing itself, however. Eventually, the pain will fix this pain system and can once again send pain alerts to the brain. However, if the TRPV1 protein is activated often, the pain system may not get a chance to repair itself in time. The person will only feel discomfort or burning at first.

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Search for:. Search Articles. Search Store. The science of heat Why chillies are hot? The Scorpion Butch T. Image credit: The Chilli Factory. He spits it out and grimaces—this one is hot. He couldn't be happier.

People have been spicing up their food with chilies for at least 8, years. At first they used wild chilies, likely adding them to potatoes, grain and corn, says Linda Perry, an archaeobotanist at Smithsonian's National Museum of Natural History. She has found traces of chilies on ancient milling stones and cooking pots from the Bahamas to southern Peru.

Based on her studies of potsherds from different archaeological sites, she concludes that people in the Americas began cultivating chilies more than 6, years ago. Just why they did is a matter of scholarly debate. Perry believes it was a question of taste. And some scholars point to medical uses. Ancient Mayans incorporated chilies into medicinal preparations for treating infected wounds, gastrointestinal problems and earaches.

Laboratory studies have shown that chili pepper extracts inhibit a number of microbial pathogens, and capsaicin has been used in a local anesthetic. Whatever the benefits, chilies spread around the world with astonishing speed, thanks in part to Christopher Columbus. In , the explorer encountered some plants cultivated by the Arawak Indians in Hispaniola. Convinced he had landed in India, he referred to them as "pepper," an unrelated spice native to the subcontinent.

The Portuguese got acquainted with chilies at their trading post in Pernambuco, Brazil, and carried them, with tobacco and cotton, to Africa. Within 50 years of Columbus' voyages, Pernambuco chilies were being cultivated in India, Japan and China.

Chilies made it to the American Colonies with the English in In the United States, where chilies were once an exotic spice, consumption increased by 38 percent between and The rise reflects both the influx of immigrants from countries where spicy food is common and more adventurous eating among the general population. According to the U. Department of Agriculture, the average American now consumes 5. When people call chilies "hot," they're not just speaking metaphorically.

Capsaicin stimulates the neural sensors in the tongue and skin that also detect rising temperatures. As far as these neurons and the brain are concerned, your mouth is on fire. Similarly, mint stimulates a type of neural receptor sensitive to cool temperatures. With enough heat, adrenaline flows and the heart pumps faster. This reaction, according to some physiologists, is part of what makes peppers so enticing. The scale that scientists use to describe a chili's heat was developed in by Wilbur Scoville, a chemist at Parke-Davis pharmaceutical company in Detroit.

He would dilute a pepper extract in sugar water until the heat was no longer detectable by a panel of trained tasters; that threshold is its Scoville rating. Last year, the naga jolokia, which is cultivated in India, rated a whopping one million SHUs. What's remarkable is that this variation can occur within a single species.

The cayenne pepper, C. The Rev. Ignaz Pfefferkorn had developed a liking for chiltepins there in the s. Pfefferkorn whose name means "peppercorn" in German called them "hell-fire in my mouth. That's when Tewksbury started wondering why chilies were hot.

Chilies, like other fruits, lure birds and other animals to eat them and disperse their seeds. But chilies also attract seed predators, like rodents, that crush seeds and make germination impossible. Many plants produce toxic or foul-tasting chemicals that deter seed predators, but these chemicals are usually found in the plant's leaves and roots as well as its fruit. In chilies, however, capsaicin is found only in the fruit—secreted via a special gland near the stem—and its production increases dramatically as the fruit ripens.

Tewksbury and Nabhan suspected that capsaicin protects chilies from rodents. To test the theory, Tewksbury wanted to compare spicy and mild chilies from the same species, if only he could find some. Bosland told Tewksbury that he had tasted an unusual chili in his greenhouse one day in Bosland took note of it, wrote it off as a mutant and placed the seeds back in the freezer.

But after Tewksbury called, he pulled them out again. Tewksbury used the seeds to grow chiles for his experiments. When he offered the fruits of those labors to laboratory packrats and cactus mice, the rodents ate the mild chilies but avoided the hot ones. Such studies convinced him "that capsaicin is all about parental care," Tewksbury says. He later found that capsaicin also has the strange effect of slowing birds' digestive systems, which helps some seeds germinate, possibly by softening the seed coat.

Birds don't mind eating capsaicin; in fact, some backyard birdwatchers spike their birdseed with chili powder to stop squirrels from raiding feeders. Even so, Tewksbury didn't believe that deterring rodents and slowing bird digestion were enough to explain why spiciness evolved in the first place.

Instead, he has come to think that a chili's heat protects it from much smaller foes. In Bolivia, fungal rot is a more pervasive threat than rodents. More than 90 percent of ripe wild chili fruits contain signs of fungal infection; it is the primary reason seeds die prior to being dispersed.