February 2007

Some Like It Hot

For anyone looking to escape the cold mid-winter blahs, biting into a searing, eye-watering, catch-your-breath chile pepper might be just the zing you need. People have long used peppers as a spice, as well as medicine. Now, researchers are finding that the pungent substance that gives chile peppers its burning sensation may also be helpful in treating certain cancers. 

The Pep in Peppers

Some chile peppers carry more of a tear-inducing wallop than others. The compound responsible for the fiery sensation in peppers is capsaicin (pronounced cap-SAY-sin). Capsaicin is an odorless, tasteless antioxidant. The only plants containing capsaicin are in the genus Capsicum, but this genus contains a lot of familiar names, including jalapenos, paprika, Tabasco, bell, and habanero. In general, the hotter the pepper, the more capsaicin it contains. Bell peppers contain little to no capsaicin, while some varieties of habanero contain so much it would cause your skin to blister.

Capsaicin (with text)Along with capsaicin, chile peppers are a good source of vitamin C, beta-carotine, and potassium.  Many also contain carotenoids, the red, orange pigments in plants which are associated with having cancer-protection and other health benefits. But it’s the pepper’s capsaicin -- its most active substance -- that has spurred recent cancer-related interest in the pungent chile pepper.


Heating It Up

Capsaicin has no flavor, odor, or color, and so finding out the amount of it in foods was quite the challenge before 1912. That was the year chemist Wilbur Scoville developed a test used to measure the hotness of peppers. The number of Scoville units measures how much capsaicin the peppers contains. Peppers (3)

In the original method -- now adapted -- Scoville added ground chile peppers to sugar-water and noted the reaction from a group of tasters. He continued to dilute the solution until the tasters could no longer sense the burning or “hotness.” The more water added, the higher the Scoville units. Although the Scoville Scale is still commonly used, researchers now measure a chile pepper’s capsaicin with laboratory techniques and then convert the rating to Scoville units. 

Pure capsaicin rates over 15 million Scoville units. Just one drop of pure capsaicin in 100,000 drops of water would be enough to blister your skin. In fact, capsaicin is so hot that researchers who handle it need to wear protective clothing and gloves, and work in a specially filtered room.

Word of Warning: If you bite into a chile dish that leaves you gasping and you need some fast relief, swig down a gulp of milk, not water. Capsaicin does not dissolve in water, but it does dissolve in fat. Milk contains a fat-dissolving substance that neutralizes the capsaicin.

Scoville Scale

Scoville Units

Chile Varieties and Commercial Products


Habanero, Scotch Bonnet, South American chinenses, African birdseye


Santaka, Chiltepin, Rocoto, Chinese kwangsi


Piquin, Cayenne Long, Tabasco, Thai prik khee nu, Pakistan dundicut


de Arbol; crushed red pepper; habanero hot sauce


Early Jalapeño, Aj Amarillo, Serrano; Tabasco ® Sauce


TAM Mild Jalapeño, Mirasol; Cayenne Large Red Thick; Louisiana hot sauce


Sandia, Cascabel, Yellow Wax Hot


Ancho, Pasilla, Española Improved; Old Bay Seasoning


NuMex Big Jim, NuMex 6-4, chili powder


NuMex R-Naky, Mexi-Bell, Cherry; canned green chiles, Hungarian hot paprika


Pickled pepperoncini


Mild Bells, Pimiento, Sweet Banana, U.S. paprika










Source: D. DeWitt, fieryfoods.com

A Killer Spice

Capsaicin’s use as a medicine dates back centuries. Early research into the antioxidant found it effective at both causing and controlling pain. In 1997 researchers found that capsaicin activates our heat sensation in the same way as that of pain. Pain-inducing nerve cells are triggered into action by capsaicin. The nerve cells send a message to the brain, which leads to the fiery sensation. Constant, relatively large amounts of capsaicin cause these nerve cells to become desensitized.

Much of the research involving capsaicin and cancer relate to cell death. A study published last year found that capsaicin leads to the death of prostate cancer cells yet leaves normal cells unharmed. The researchers found capsaicin causes the death of about 80 percent of prostate cancer cells in mice. When mice with prostate tumors were treated with capsaicin, the tumors shrunk by about one-fifth the size of untreated tumors.

Soon after that study was published, mice with pancreatic cancer were in the spotlight. After mice were fed capsaicin the tumors were about half the size of those in regular-munching mice. As in the previous study, there was no affect on normal pancreatic cells.

Now researchers from the United Kingdom may have identified a key to how capsaicin contributes to the death of cancer cells. Using lung and pancreatic cancer cells, the researchers found that capsaicin disrupts a cancer cell's major energy source: the mitochondria. The result was that the cancerous cells died, yet there was no harm to the surrounding healthy cells.

Adding Pepper to Your Health

Research in capsaicin and cancer is still preliminary and in the laboratory stage. The cancer benefits seen with capsaicin in laboratory studies involve a lot of capsaicin. In order to equal the capsaicin fed to mice in the prostate cancer study, for example, a 200-pound person would have to eat about eight habanero peppers (400 milligrams) -- one of the hottest peppers in the world -- every week. And while capsaicin does show promise in cancer treatments, eating too much of the compound can be harmful.

habaneros: the world's hottest pepperSo while scientists are figuring out the what’s and how’s behind the compound, you can enjoy chile peppers from mild to fiery simply for their zesty taste, knowing they contain multiple health benefits.

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