It’s hard to deny the popularity of the chile pepper (Capsicum annuum). This fiery fruit originated in Mexico thousands of years ago. Over the past few centuries, it’s become an indispensable ingredient in cuisines around the world.

Today, Asian-Pacific countries dominate the hot pepper market, but there’s a growing devotion in the West. too. A global shortage of a popular brand of Sriracha hot sauce in 2023 reportedly led some Sriracha fans to pay as much as $150 for a bottle that usually costs $5.

Peppers do much more than spice up food. Research shows that chiles can relieve pain, reduce blood pressure, lower your risk of Type 2 diabetes, and even possibly help you lose weight.

One population-based study published in the BMJ in 2015 suggests that the more peppers people eat, the more resilient they become. Researchers observed that devoted pepper-eaters were less likely to die from cancer, ischemic heart disease, and respiratory illness.

“Compared with those who ate spicy foods less than once a week, those who consumed spicy foods 6 or 7 days a week showed a 14% relative risk reduction in total mortality,” researchers wrote.

This all-mortality risk reduction was even stronger among spice-loving consumers who also didn’t drink alcohol.

The more that scientists probe hot pepper health benefits, the more it appears that chiles make for stronger, more energetic individuals. One study shows that chiles can have a beneficial effect on muscle strength, while other research shows that men who eat chiles tend to have higher testosterone levels than males who prefer mild meals.

The Health of Heat

It’s clear that chiles have a lot going for them, but it’s that spicy burn that makes people hungry for hot peppers.

However, such a craving seems counterintuitive. In the endless quest to find something to eat, we naturally seek pleasant tastes such as sweetness and saltiness. But what would make us seek food that causes pain? Other mammals avoid hot peppers, and instinctively reject their spicy bite, so why have they become so popular with people?

To watch a hot pepper-eating contest is to witness the face of absolute agony. And yet, every few years, someone manages to produce an even spicier pepper specimen, tempting chile lovers with an even more agonizing experience.

Perhaps part of us knows that chile pain is beneficial. Capsaicin is the chemical that gives peppers their signature sting. It is also where researchers have found the bulk of chiles’ medicinal value.

Long before capsaicin was first isolated in 1816, doctors used chiles to treat a number of ailments, but a particularly common prescription was for pain. How can a food notorious for inflicting pain also be used to relieve it? According to the philosophy of homeopathic medicine, this is the principle of “like cures like,” the idea that a substance known to cause a particular reaction in a healthy person can be used to treat those who suffer from similar symptoms.

The Reward Factor

Science has since discovered several other mechanisms responsible for chiles’ analgesic effects. One is the idea that through pain comes pleasure. Researchers have found that eating hot peppers stimulates the body to release feel-good chemicals such as endorphins and dopamine. It’s as if to cope with the searing heat of capsaicin on the tongue, the body generates its own reward.

The research also suggests the analgesic effect of capsaicin might be associated with increased activity of the cerebral opioid system—the same system stimulated with much harder drugs such as heroin and morphine.

Another aspect of the pain-relieving magic of hot peppers is that it increases blood circulation. Capsaicin acts on nerves to release neuropeptides, which in turn activate a vasodilator known as nitric oxide. The result is better blood flow, a decrease in blood pressure, and pain reduction.

Details of chiles’ pain-relieving effect have been found where capsaicin molecules meet our cells.

The flavor of a particular chile pepper may have sweet or savory notes. However, we experience its heat through temperature receptors, not taste receptors. When you bite into a pepper, capsaicin molecules connect with temperature receptors on your tongue known as the heat-sensitive transient receptor potential vanilloid type-1 cation channel, or TRPV1 for short.

TRPV1 is tripped anytime your tongue touches a heat source. Take a sip of tea, for example, and the sensory input of TRPV1 lets you know if your beverage is ready to drink or still too hot to handle.

Hot But Not

Capsaicin also stimulates TRPV1, but it creates only an illusion of heat. Depending on the spice level of the pepper, that illusion can become extremely intense. You may even feel as if your entire intestinal tract is on fire.

TRPV1 is found throughout the body. Rub your eyes or elsewhere after handling chopped habaneros and a burning sensation at that location is sure to flare up. The experience may be excruciating, but you’re not really on fire. Even for those who suffer the hottest of peppers, the pain fades after a few minutes.

However, researchers have found that this burning illusion peppers provide can actually stimulate the body to repair underlying features of other types of pain.

In a clinical trial published in a March 2023 edition of the journal Pain, researchers studied people with nerve pain. With just a single application of a topical, high-concentration capsaicin treatment, they found “a significant reduction in pain intensity,” with more blood flow observed at the pain site.

“Half of the patients not only showed a functional recovery but also an improvement in vasodilatation, indicating regeneration of nerve fibers,” researchers wrote. “The degree of vasodilatation significantly correlated with pain reduction.”

This study suggests that capsaicin can have a lasting pain-reductive effect. But keep in mind that not everyone will experience favorable effects.

Not for Everyone

The problem for some isn’t the capsaicin. Peppers are part of the Solanaceae family of plants, otherwise known as nightshades. Some other Solanaceae plants are tomatoes, eggplant, potatoes, goji berries, and ashwagandha. Nightshades contain a small amount of a chemical called solanine. The chemical is found in the highest concentration with poisonous nightshades, though most of us can eat nightshade vegetables with no ill effects. However, for people who are particularly sensitive to the chemical or who have a solanine allergy, nightshades have been known to instigate inflammation and arthritis.

A Better Burning Metabolism

Even people without nightshade sensitivities may shy away from peppers—because they simply can’t take the heat. In doing so, they’re missing out on a wealth of nutrients. Even the mild varieties are a rich source of minerals and vitamins and are particularly high in Vitamin C. Chiles also contain fiber, flavonoids, and other antioxidants. Plant sterols found in peppers may help lower cholesterol.

And these spicy, nutritious plants come with another benefit. While most foods seem to cause us to pack on the pounds, chile peppers might help take them off.

Several studies cite peppers as an anti-obesity food, as epidemiological data have shown that hot peppers are associated with a lower prevalence of obesity. Animal models show it in action. One study found that rodents who were fed a diet containing a minute amount of capsaicin showed no change in caloric intake but a nearly 30 percent reduction in visceral fat weight.

How Does It Work?

Peppers aid weight management from a number of angles. One way is that peppers increase intestinal blood flow, thereby improving nutrient absorption while decreasing blood flow to fat tissue.

A 2016 review of human studies with chile peppers published in the International Journal of Food, Science, and Nutrition confirms that hot peppers can contribute to weight loss. This research found that chiles helped shed pounds by improving energy expenditure and fat metabolism.

Part of these benefits come when capsaicin activates TRPV1. This creates an increase in our body’s intracellular calcium levels and triggers the sympathetic nervous system.

Another slimming feature of chiles is that they have been found to activate what is called brown fat. Compared with white fat (which simply hangs over your belt and builds up with excess calories) brown fat is more metabolically active, meaning you burn more calories even at rest.

Brown fat also breaks down blood sugar, and chiles have been shown to improve insulin control, suggesting that these spicy fruits may help with diabetes.

Of course, chiles are no replacement for exercise and a good diet, but they may certainly lend a helping hand—and you may not need much to make a difference. The positive effects on weight management with chile peppers in human studies were seen in a wide range of doses: from consumption of a single spicy meal to tracking regular chile pepper consumption for up to 12 weeks.

Another way hot peppers may help with weight management is by making meals more satisfying. One study found that consuming capsaicin decreases the desire to eat after dinner.

However, in a 2022 review evaluating capsaicin in weight control, researchers found some limitations. Although peppers may suppress appetite in the short run, they cannot protect against obesity in the long run. Large epidemiological studies found no significant difference in BMI between those who eat chiles and those who don’t. That’s because over time, we become desensitized to the effects of capsaicin. This is why veteran chili eaters can consume heavily spiced dishes with no discomfort.

Although chile peppers may not be a magic weight-loss pill, researchers have said there is still good evidence that it may play an important role in body weight regulation.

“Capsaicin seems to have a beneficial direct effect on gut microbiota, by promoting the growth of ‘anti-obesity’ bacteria and eliminating undesired pathogens,” researchers wrote in the 2022 review.