Is Spicy a Taste or Pain?

Spicy Isn’t a Taste; It’s Chemistry (and a Little Self-Sabotage)

Source: The Guardian  “Why do people love spicy food, even when it hurts to eat it?” (Nov 10, 2025)
https://www.theguardian.com/lifeandstyle/2025/nov/10/why-do-people-love-spicy-food-even-when-it-hurts-to-eat-it

Spicy food is one of the only times we voluntarily eat something and then immediately act like we regret every life decision, sweating, tearing up, and chugging water like it’s going to save us (spoiler: it usually doesn’t). But that “burn” isn’t actually a flavor like sweet or salty. It’s chemistry messing with your nervous system.

The article explains that “spicy” is not a normal taste. The burning sensation comes from capsaicin, a chemical in chili peppers that triggers heat- and pain-sensing nerves in your mouth. Your brain reads that signal as heat and irritation, which is why spicy food can cause sweating, tearing, and a burning sensation. The article also explains why many people still enjoy spicy food: with repeated exposure, the body can become less sensitive, and the brain can start treating the discomfort as “safe,” kind of like enjoying a roller coaster or a horror movie.

The Chemistry: Why It Burns

Capsaicin binds to TRPV1 receptors, which are proteins on nerve cells that normally detect dangerously high heat. When capsaicin binds, it activates the receptor and sends a signal that feels like burning, even if the food isn’t physically hot.

Why Water Doesn’t Help

Capsaicin is mostly nonpolar (hydrophobic) because it has a long hydrocarbon “tail.” Water is polar, so it doesn’t dissolve capsaicin well (“like dissolves like”). When you drink water, the capsaicin often doesn’t wash away; it can spread across your mouth and contact more TRPV1 receptors, which is why the burn can feel worse.

Why Milk Helps

Milk can interact with capsaicin much better than water. Casein proteins form structures called micelles (like tiny molecular “soap bubbles”) with hydrophobic regions that can trap capsaicin and help pull it off your mouth tissues, so less is left to activate TRPV1. If the milk has fat (whole milk, yogurt, ice cream), that helps too because capsaicin is fat-soluble, so it dissolves into the fat instead of staying stuck in your mouth. In short, milk helps remove capsaicin, while water mostly moves it around.

Resources

1. The Guardian. “Why do people love spicy food – even when it hurts to eat it?” (Nov 10, 2025).

https://www.theguardian.com/lifeandstyle/2025/nov/10/why-do-people-love-spicy-food-even-when-it-hurts-to-eat-it

2. Penn State University (Research News). “Proteins in milk — not just fat — may help reduce oral burn from spicy food.” (Jan 31, 2024).

https://www.psu.edu/news/research/story/proteins-milk-not-just-fat-may-help-reduce-oral-burn-spicy-food

3. First picture: https://scitechdaily.com/dinner-too-spicy-scientists-discover-natural-anti-spice-compounds/

4. Second picture: https://pubchem.ncbi.nlm.nih.gov/compound/Capsaicin

5. Third picture: https://www.researchgate.net/figure/Transduction-mechanism-by-which-capsaicin-activates-TRPV1_fig3_381575553