Food safety authorities in Denmark have recalled three types of South Korean spicy instant noodles over possible risks of “acute poisoning”. According to the Danish Veterinary and Food Administration, “the capsaicin content [in the noodles] is so high that it can pose a health hazard”, especially to children. Capsaicin is the chemical which makes chili peppers spicy. Fiery mind trick Capsaicin is most abundantly found in the “placenta” (white membrane to which seeds are attached) of some chili peppers — fruits of plants of genus Capsicum, which were introduced to the rest of the world from South and Central America by Christopher Columbus. The chemical binds to TRPV1 receptors in humans’ nose, mouth, skin, and insides. These receptors help in detecting heat (and pain), and are most commonly activated by a rise in temperature. But capsaicin ‘tricks’ them into reacting, even though there is no actual temperature rise. The brain, thus, believes that the body is on fire, causing the painful, burning sensation associated with consuming chilis. The body then tries to cool down — hence the sweating, and the red face (capillaries just below the skin dilate, as blood rushes to the surface of the body, where it can radiate heat away more easily). The runny nose or teary eyes (if capsaicin happens to come in contact) are the body’s attempt at expelling the heat-causing element. So are the gut cramps and diarrhea. Evolutionary benefits In 2001, biologists Josh Tewksbury and Gary Nabhan conducted a feeding experiment on some birds and rodents. They found that while the former tended to avoid chilis, the latter ate them like candy (“Directed Deterrence by Capsaicin in Chilies,” published in Nature in 2001). The researchers attributed this to the fact that birds do not have TRPV1 receptors, unlike rodents (and mammals). Tewksbury further found that unlike rodents, birds acted as seed dispersers. The seeds they consume (and poop out) germinate at high rates, whereas rodents tend to crush seeds while chewing. Capsaicin, thus serves a specific evolutionary purpose for chili plants. (“Evolutionary Ecology of Pungency in Wild Chilies” published in PNAS in 2008). Later research has also found that the chemical protects against certain fungi and insects. But developing capsaicin comes at a cost. It consumes a significant amount of the plant’s limited resources, especially nitrogen and water. This makes spicy chilis more prone to droughts (David Haak, et al “Why are not all chilies hot? A trade-off limits pungency” published in Proc R Soc in 2011). Loving the burn Yale psychologist Paul Bloom once said, “Philosophers have often looked for the defining feature of humans — language, rationality, culture and so on. I’d stick with this: Man is the only animal that likes Tabasco sauce”. It is clear that chilis evolved so as to not be consumed by mammals, but (many) humans still love it. Today, the five domesticated chili species have been bred to more than 3,000 different cultivars (or cultivated varieties) which vary in terms of colour, taste, and pungency. Some experts argue this love for spicy foods (not just chilis, but also other foods like peppercorn or wasabi) comes from the antimicrobial benefits they possess. “Countries with hotter climates used spices more frequently than countries with cooler climates,” biologists Jennifer Billing and Paul W Sherman wrote in “Darwinian Gastronomy: Why We Use Spices” (published in the QRB in 1998). This is because food spoils much faster in hotter environments. Native Americans, for instance, used (and continue to use) chilis not just to add a spicy kick to food but to preserve it. “People who enjoyed food with antibacterial spices probably were healthier. They lived longer and left more offspring.” the researchers wrote. Psychologists have a different view. In their pioneering research paper, Paul Rozin and Deborah Schiller argued that chili lovers “come to like the same burning sensation that deters animals and humans that dislike chili… eating chilis [like] riding on roller coasters… can be considered instances of thrill seeking or enjoyment of ‘constrained risks’” (“The nature and acquisition of a preference for chili pepper by humans”, published in Motivation and Emotion in 1980). Emphasis here on the word ‘constrained’ — the burn is ‘simulated’, much like a roller coaster drop, meaning that chilis do not actually pose a ‘real’ risk. Word of caution That being said, too much capsaicin can still be harmful. In high concentrations, the chemical can produce heartburn, gastrointestinal pain, and diarrhea. Moreover, long-term ingestion of high levels of capsaicin may lead to several chronic gastrointestinal disorders. But ‘poisoning’, as flagged by Danish authorities, is rare simply because of the levels of capsaicin that need to be ingested before it becomes toxic. If humans are as sensitive to capsaicin as mice, a person weighing 70 kg would have to consume roughly 2.5 litres of Tabasco sauce to overdose (Manirakiza, Covaci and Schepens in “Pungency Principles in Capscicum” in Capsicum: The Genus Capsicum, 2003). But there is still more scope for research, and given capsaicin’s gastrointestinal effects, high dosages are avoidable. Danish authorities acted after a social media trend, which saw children and teenagers daring each other to eat “a strong bowl of noodle soup”, went viral. Such “challenges” are not new, and previously, have been known to be deadly. In September 2023, a Massachusetts teen with a congenital heart defect died after participating in a spicy tortilla chip challenge.
