Bite into a hot pepper, or chilis, and you’ll instantly feel the ‘flame effect.’ But can these fiery fruits actually boost your metabolism and promote weight loss?

To a degree, the scientific answer is yes.

Chilies get their heat from an oily chemical compound called capsaicin, which is concentrated in the membrane surrounding the seeds of the Capsicum plant. In studies, Capsaicin boosts thermogenesis—the process by which the body turns calories into heat to use for fuel. However, the effect on weight loss is modest, at best. Here’s why:

Given the pungency of peppers, it’s difficult for anyone, even a person with a great tolerance for spicy foods, to eat hot peppers often enough and in a sufficient enough serving to lose weight via the ‘chili pepper effect.’

Even though we can’t eat enough hot peppers to result in weight loss, including chilies in your diet promotes good health in other ways. Chilies are rich in vitamins A, E and K and potassium. Additionally, in scientific studies capsaicin (in capsule form) has been shown to help reduce pain and inflammation, boost immunity, lower the risk for Type 2 Diabetes, and clear congestion associated with colds.

Caution: Biting into a raw or cooked chili pepper creates an intense heat inside the mouth (the flame effect). If that happens to you, drink milk or eat cottage cheese or plain yogurt to tame the heat. Also, if you’re not accustomed to eating chilis your throat may swell and your body may react to the peppers and cause you to vomit.

The Hottest of the Hot
The Scoville scale measures the heat of chili peppers. The following list shows chilis in the order of their Scoville Heat Units, from high heat to modest heat:

Habaneros and Scotch bonnets
Cayenne pepper
Tabasco pepper
Thai chili pepper
Jalapeno and Serrano chili peppers

Hot Tip: If you can’t remember which are the hottest of the hot peppers, look at the thickness of the stem. The thinner the stem, the hotter the pepper (and higher the capsaicin). Red peppers are hotter than green

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Greenaway, T. “How Hot is that Pepper? How Scientists Measure Spiciness” Smithsonian Mag Online. Accessed on March 8, 2016 “Chili Pepper, Dried.” Accessed on March 8, 2016.

Gamboa-Gómez, Claudia I. et al. “Plants with Potential Use on Obesity and Its Complications.” EXCLI Journal 14 (2015): 809–831. PMC. Web. 8 Mar. 2016.

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“Fruit or Vegetable: What is a Chili Pepper?” Accessed on March 8, 2016
Accessed on March 8, 2016

The Chili Pepper Institute. University of New Mexico. Accessed on March 8, 2016.