Although small in size at just 2 to 4 inches long, the jalapeno pepper packs a nutritional punch, with notable amounts of two important vitamins. Jalapenos are just one variety of chili pepper, a nightshade vegetable well known for a hot and pungent flavor. These little peppers derive their heat from a natural plant compound called capsaicin, which offers powerful health benefits.
Jalapenos are mostly available green, turning red as they mature. These peppers contain a negligible amount of calories, with only 4 calories in one pepper. They also have less than a gram each of protein and fat and just 0.91 gram of carbohydrates in a serving, making them a good choice for low-carb diets.
Like other peppers, jalapenos are a rich source of vitamin C, with almost 17 milligrams in a small pepper. That is equal to 18 percent of the recommended daily allowance for men and 23 percent for women. Vitamin C is an antioxidant that helps prevent damage from free radicals, rogue molecules that can cause cell damage in your body. Jalapenos also supply a good amount of vitamin A, which supports skin and eye health; one pepper offers 17 percent of the RDA for men and 22 percent for women.
The Scoville scale measures the capsaicin in various peppers. Jalapenos rank as medium on the scale, with 2,500 to 8,000 Scoville heat units per pepper, according to Rebecca Wood, author of “The New Whole Foods Encyclopedia.” Capsaicin has impressive health benefits, particularly as an anti-inflammatory and vasodilator that promotes healthy blood flow. In addition, a study in the journal “Cell Signal” in 2003 concluded that capsaicin is “promising” for treatment of cancer because it appears to turn off NF-kB, a protein that promotes tumor growth. Capsaicin has also shown promise for weight loss, especially of hard-to-lose belly fat, by increasing energy expenditure after consumption.