I recently had the pleasure of visiting Mexico.  I didn’t go to the usual tourist spots of Cancun or Cozumel, or even the infamous Tijuana, but rather to the central Mexican city of León.  I was there to attend a scientific conference, and I have to say our Mexican hosts were wonderful and showed great hospitality.  One of the things I enjoy when visiting other countries, is to try the food that’s eaten by the local people, and on this trip, I was not disappointed.  As anyone who has tried Tex-Mex food, or authentic Mexican cuisine will know, is that chili peppers often play a prominent role.  At one dinner, sampling some local peppers and feeling the sweat appear on my brow, I was enthralled by how something so small could have such a large impact on the body.  Now I don’t know if you’re anything like me, but feeling the somewhat masochistic delight of causing pain to my mouth and tongue on eating chilies, I naturally wondered if you could poison someone with chili extracts.

       The substance that gives chili peppers their intensity when eaten is capsaicin, and related compounds called capsaicinoids.  As one would expect, the more capsaicin in a pepper, the hotter it tastes.  The heat is determined by the Scoville scale, the standard measure of spiciness.  This year, a new pepper was cultivated and given the name Dragon’s Breath, honouring its birth country of Wales, and measuring 2.5 million on the Scoville scale.  The next hottest pepper on the list, the Carolina Reaper has a mere 2.2 million rating on Scoville, while the Bhut Jolokia pepper, better known as the infamous Ghost Pepper, comes in at a respectable 855,000 units.  The jalapeño that I was eating in Mexico came in with a rather lame 2,500 Scoville units. 

The capsaicin in chilies is actually a neurotoxin, and interacts with a heat-detecting protein receptor in our nerves called TRPV1.  Once activated, the nerves send signals to the brain that it is in danger from overheating, possibly even being sustaining burns. The more capsaicin in a chili the more we sense heat!  But why do we derive pleasure from inappropriate activation of pain nerves? Well the brain produces endorphins to block the pain, and in so doing produces a sense of happiness and euphoria.  Despite trying to block out pain, the brain still sends signals to the rest of the body to deal with the perceived threat.  Anyone who has ever eaten hot chilies will instantly recognize these responses. The body starts sweating to try and cool down.  Capsaicin irritates the mucous membranes of the nose causing it to respond by making more mucus and causing a runny nose.  As the chilies make their way to your throat, a burning sensation may be felt at the back of the mouth.  Once in the stomach, capsaicin again irritates the lining of the stomach leading to stomach cramps as the body tries to get the offending chemical into the intestines and out of the body as quickly as possible.  Glands in the wall of the intestines may secrete more fluid into the intestine to try and flush out the irritating chemical, leading to chili diarrhea.  Even the hands and face will flush red as the body tries to cool down.

      Despite the body’s responses to what appears to be a real threat, is there any danger to eating really hot chilies?  On a Saturday night in October, emergency services were called to a restaurant in St. Leonards Place, Edinburgh, where several individuals were writhing in agony on the floor, vomiting and fainting.  One of the restaurant patrons, a 21-year-old Korean exchange student had to be taken to the emergency room of the local hospital twice.  “I got it really bad.  I have never endured such pain in my life”.  What linked these restaurant customers?  They were all contestants in Kismot Restaurant’s “Hottest Chili Challenge” where contestants were asked to sample the restaurant’s Kismot Killer.  Despite the multiple ambulances appearing at his restaurant, the owner, Mr. Ali, said he felt the competition had gone well.  An article appearing in the British Medical Journal recounts the case of a 34-year-old male eating Carolina Reaper peppers as part of a pepper eating contest.  After one pepper, the man started dry heaving and developed a severe pain in his neck that evolved into a series of thunderclap headaches; severe sudden episodes of excruciating pain.  A CT scan of the brain revealed numerous narrowed arteries, a condition known as reversible cerebral vasoconstriction syndrome (RCVS), which probably caused the intense headaches.  In rare cases, RCVS can lead to strokes.  In 2016, a 47-year-old man almost died after he tore his oesophagus by retching and straining to vomit after eating pureed ghost pepper.  In 2012, an otherwise healthy 25-year-old male was admitted to hospital complaining of severe chest pain after eating cayenne pepper pills.   In the same way capsaicin can cause vasoconstriction (narrowing of the blood vessels) in the brain, it can also do the same in the heart, causing severe constriction of the coronary arteries.  Cutting off the supply of blood to the heart muscles caused a severe heart attack, with significant damage to the heart muscle.  Only the prompt arrival of the patient at the emergency room saved his life.

      At 4:16 pm at the beginning of January, 2013, police and emergency services were summoned to the 20000 block of Cayuga Road in Apple Valley California, a town 90 miles east of Los Angeles.  21-year-old Amanda Sorensen was at home caring for her boyfriend’s daughter, two-year-old Joileen.  Amanda had called the emergency service operators telling them that Joileen had started coughing uncontrollably and had turned blue.  Sorensen said that she was trying to give CPR to the distressed child. When paramedics arrived, they found Joileen on the floor suffering from seizures. The toddler was immediately rushed to a nearby hospital but was pronounced dead on arrival.  Given the nature of the child’s passing, an autopsy was performed to discover the exact cause of death.  Forensic pathologist Dr. Rhee stated death to have resulted from “asphyxia due to forced inhalation of chili powder”, concluding that death likely occurred within minutes of exposure.  Sorensen told police that the toddler had gotten into the kitchen on her own, and eaten the chili powder, likely mistaking it for candy.  However, abrasions and contusions on the cheeks were consistent with forced feeding, and Joileen’s death was ruled a homicide.  Shortly thereafter, Amanda Sorensen was arrested for Joileen’s murder.  Following an extensive police investigation, it transpired that Sorensen had used the chili power as a punishment for Joileen lying to her.  Sorensen went into the kitchen and grabbed a bottle of chili powder and brought it back to the infant.  As a struggle ensued, Sorensen grabbed the child’s face and forced the contents of the chili powder bottle into Joileen’s open mouth.  As the Joileen continued to struggle, trying to spit out the powder, Sorensen clasped her hand over the child’s mouth, repeatedly ordering the toddler to “swallow it”.  It was at this point that Joileen started coughing and turning blue.  The presence of capsaicin in the airways triggered a massive response closing down the airways, making it impossible for Joileen to get life-giving oxygen into her small lungs.   Without oxygen, Joileen collapsed, convulsed and died.  Following a plea deal that saw Sorensen admit guilt to second-degree murder.  Sorensen was sent to jail for 15 years for the death of Joileen.

Finally, what’s the best way to quench that chili fire burning in your mouth?  Fortunately for all of us, there are scientists who have performed extensive research in this area.  Perhaps not surprisingly, they have found support for what everyone likely already knows: drink milk not water. Milk is best as a quencher, probably for two reasons.  One, the milk protein casein dulls the pain by kicking off capsaicin from the nerve’s pain receptor.  Secondly, capsaicin is soluble in milk fat, soaking up excess capsaicin hanging out in the mouth.