Last year when I was researching wax, I mentioned large armadillo-like creatures that secrete a waxy substance high in capsaicin, and how that product might impact trade. Now I'm finally getting a chance to pull together my notes on capsaicin;
- Approximately a quarter of the world's population eats hot peppers daily.
- Capsaicin is an evolutionary adaptation in chili peppers; it generally keeps mammals from eating the plant because mammalian digestive processes will destroy the seeds.
- Birds don't react to capsaicins the way mammals do, which is good for chili pepper plants; birds don't grind up the seeds with their teeth and destroy it with their guts — they help spread the seeds.
- Fusarium fungus is the main reason chili seeds die before dispersal; capsaicinoids are an evolutionary adaptation to protect chili seeds from Fusarium and other fungal infections.
- Menthol (like from mint plants) is basically the opposite of capsaicin, it stimulates a sense of cold.
Bound to Burn
Capsaicin is a natural alkaloid derived from pepper. It causes mammals to feel a "burning pain" sensation because it binds to the same ion pathways we use to detect dangerous heat levels, which has implications for thermoregulation. It causes hypothermia in rats, followed by hyperthermia. Capsaicin can suppress the heat sensitivity of cockroaches.
Mammalian vanilloid receptors only recently developed the ability to detect capsaicin-like inflammatory substances. Vanilloid receptors are calcium-permeable channels in invertebrates (nematodes, insects) and vertebrates (mammals). They're sensitive to a bunch of different kinds of stimuli, including chemical, mechanical, osmotic and temperature.
Capsaicinoids can provide pain relief, cancer prevention and weight loss. Topical application of capsaicin reduces arthritis pain, diabetic neuropathy, psoriasis, etc. Capsaicin inhibits acid secretion, stimulates alkali and mucus secretion and particularly gastric mucosal blood flow which helps in prevention and healing of gastric ulcers. It also has antioxidant and anti-inflammatory properties.
Early humans likely selected chilies for use and domestication expressly because of their antimicrobial properties; they were one of the first plants domesticated in the Americas and were domesticated by several independent groups at least a millennium before a village-farming way of life became widespread.
📗 If you found this interesting, you may also enjoy my previous newsletter about weird ways different animals thermoregulate.
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