How you choose to spell these fruits are based by where you choose to reference their origin. In Mexico and Latin American Countries, they prefer Chilé. India, Australia, Britain and most Europeans reference these fruits as Chilli. Lastly, as we do with most words here in America, we changed the spelling to Chili. Which has led to some confusion in the distinction between a "bowl of chili" and a "bowl of chili peppers".
Capsaicinoids, which are produced within the life cycle of a chilé are what bind to the heat and pain abrasion receptors in your nose or mouth. Capsaicinoids give you a burning sensation dependent on the level of intensity found in that individual chilé. Note, there is no amount of capsaicin that can physically harm you, nor damage any tissue. It is also true, that you can build up a tolerance to this burning sensation by depleting these receptors with continuous ingestion. Knowing this should relieve your fear when offered a new chilé. The irony about chilés and the beauty of the pain they produce. Is that the endorphins, (a class of compounds that act as natural painkillers in the body) lead you to a "state of well-being."
The intensity or heat level of a chilé is measured most commonly by the Scoville scale. Where a mixture of sugar and water is incrementally added to the extract of a dried chilé and tested by a panel of 5 individuals. The more scientific and less common method is having the extract forced through a column under high pressure for the separation of the mixture for reference as to the range of heat. Imagine a Habanero chilé at 350,000 units to the contents of pepper spray at 5,300,000 units. Pure capsaicin comes in at 16,000,000 units, which is available in some markets. If you should find yourself in a position of "Way Too Much Chilé in the Mouth" ...Drink Milk! Remember, no physical damage will result other than an intense burn on both ends.
Chilés originate from Mexico and date as far back as 7500 B.C. Explorers from the East that were involved in the Columbian Exchange of the 15th and 16th century were responsible for chilés spreading throughout the rest of the World. Chilés quickly became a commodity in Asia that complimented the others spices being traded during this time. Upon Christopher Columbus returning to Spain, he presented his gifts to the Queen and among those were chilés. Columbus referred to the fruit as "Peppers" which related to the effects of black pepper. Hence, the beginning of "Chilli Peppers".
In Spanish and Portuguese monasteries chilés were grown as a botanical curiosity and later used in medicine. No matter how or when they arrived, chilés are grown on over 9 million plus acres throughout the Earth. Creating the opportunity for anyone to enjoy the many unique tastes and levels of intense heat, while sharing in cuisines from various cultures worldwide!