Why Does Chili Feel Hot? The Science of Spicy Food

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1. 01Why Does Chili Feel Hot?

   Good afternoon, everyone. I grew up in Mexico City, where chili is part of almost every meal. But I never asked a simple question until recently: why does chili feel hot, even when the food is cold? Today, I'll explain the science.

   大家午安。我在墨西哥城長大，在那裡，幾乎每頓飯都有辣椒。但直到最近，我才想到一個簡單的問題：為什麼辣椒會讓人覺得燙，即使食物是涼的？今天，我來講講其中的科學原理。

2. 02The Key Ingredient: Capsaicin

   The answer starts with a chemical called capsaicin. It's the substance in chili peppers that gives them their spicy "burn."

   答案要從一種叫辣椒素的化學物質說起。它就是辣椒裡產生那種火辣「灼燒感」的物質。

3. 03A Heat Sensor in Our Body

   Our nerves have tiny sensors called receptors. One of them, called TRPV1, normally reacts to heat that is hot enough to hurt. When it's activated, it sends a signal to the brain that says, "Hot!"

   我們的神經上有一些微小的感受器，叫作受體。其中一種叫TRPV1，通常會對熱到讓人疼痛的溫度產生反應。它被啟用時，會向大腦發出一個訊號：「好燙！」

   Source: The Nobel Prize in Physiology or Medicine 2021, press release (NobelPrize.org)

4. 04Capsaicin Tricks the Sensor

   Here's the clever part. Capsaicin can switch on the same TRPV1 sensor, even without any real heat. So when you eat chili, your brain receives the same message as if your mouth were being burned.

   巧妙的地方就在這裡。即使沒有任何真正的熱量，辣椒素也能啟用同一個TRPV1感受器。所以當你吃辣椒時，你的大腦收到的資訊就和你的嘴被燙到時一樣。

   Source: The Nobel Prize in Physiology or Medicine 2021, press release (NobelPrize.org)

5. 05A Nobel Prize Discovery

   This sensor was discovered by the scientist David Julius, who used capsaicin to find it. In 2021, he shared the Nobel Prize in Physiology or Medicine for discovering receptors for temperature and touch.

   這個感受器是科學家戴維·朱利葉斯發現的，他正是利用辣椒素找到了它。2021年，他因發現溫度和觸覺的受體而共同獲得了諾貝爾生理學或醫學獎。

   Source: The Nobel Prize in Physiology or Medicine 2021, press release (NobelPrize.org)

6. 06Why Water Doesn't Help Much

   This also explains a common mistake. Many people drink water when food is too spicy, but capsaicin doesn't mix well with water, so the burning often continues. In my family, we eat a little rice or bread instead.

   這也解釋了一個常見的誤區。很多人在食物太辣的時候會喝水，但辣椒素不太溶於水，所以灼燒感往往還會持續。在我家，我們會吃一點米飯或麵包。

   Source: The Conversation, "Why doesn't water help with spicy food? What about milk or beer?" (2024)

7. 07Why We Still Love It

   So why do we eat something that tells our brain we're in pain? For many people, the burn is part of the fun. It adds excitement and flavor to food, and in many cultures, it's simply part of home.

   那麼，我們為什麼要吃一種讓大腦以為自己在疼的東西呢？對很多人來說，這種灼燒感正是樂趣的一部分。它給食物增添了刺激和風味，而且在很多文化裡，它就是家的味道。

8. 08Conclusion

   To sum up, chili doesn't actually burn us. It tricks a heat sensor in our nerves. The next time you eat something spicy, you'll know exactly what's happening inside your mouth. Thank you.

   總結一下，辣椒其實並沒有燙傷我們。它只是騙過了我們神經裡的一個熱感受器。下次你吃辣的東西時，你就會清楚地知道嘴裡發生了什麼。謝謝大家。