The Science of Spicy Foods

By Dan Mahoney

Spicy foods are a staple of some cultures’ culinary tastes. But what explains the appeal to some of a food that others consider painful? If you tend to dismiss the heat of a spicy food as more of a nuisance than a benefit, you may be surprised to know there’s a lot going on in our bodies when we eat something spicy.

What Makes Spicy Food Spicy?

There are receptors in our bodies clustered around our mouth and skin that typically activate when exposed to atmospheric heat, generally over 109°F. But that’s heat as measured by the thermometer, not our taste buds. So what is it about a “hot” pepper, whether it’s no warmer than room temperature or even refrigerated, that sends us running for a glass of water after we take a bite?

The substance found in “hot” food that humans react to in this way is called capsaicin. Capsaicin triggers these same receptors to induce a feeling of burning — a feeling that can affect the mouth, stomach, eyes and skin when in contact, extreme levels of which can even cause nausea or difficulty breathing.

How “Hot” Can These Foods Get?

The heat levels in food are measured in Scoville Heat Units (SHUs), which gauge our sensitivity to capsaicin. Developed in 1912 by Wilbur Scoville, this metric may not be as accurate as liquid chromatography methods, but it is still recognized today as the standard for spicy heat measurement.

Starting the scale at 0 SHU is a bell pepper. Other commonly known peppers include the banana pepper, scored at up to 900 SHU; the jalapeno, which can reach up to 10,000 SHU; and the habanero, measuring up to 350,000 SHU. There are actually varieties of peppers that go all the way up to 2,200,000 SHU! Growers breed these extreme varieties by mixing strains of peppers to create specific traits like heat or sweetness.

Why Would We Eat Hot Foods

Several studies have been conducted to evaluate the potential health benefits associated with eating spicy foods. One such study, published in August 2015 by the Chinese Academy of Medical Sciences, suggests that spicy food can extend life. Almost half a million people in China reported their intake of spicy foods for the study, the results of which showed that people who ate spicy foods six or seven times per week reduced their total risk of mortality by 14 percent compared to those who ate spicy foods no more than once per week. While people with cancer, heart disease and stroke were excluded from the study, it didn’t take into consideration other dietary, environmental or health considerations.

In addition to this recent Chinese study, other evidence suggests spicy food can increase metabolism, speed up the feeling of being full, and possibly even decrease “bad” cholesterol to improve blood circulation. While such reports may associate health benefits with the consumption of spicy foods, that doesn’t mean adding hot sauce will make a bacon cheeseburger “healthy!”