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.

   大家下午好。我在墨西哥城长大，在那里，几乎每顿饭都有辣椒。但直到最近，我才想到一个简单的问题：为什么辣椒会让人觉得烫，即使食物是凉的？今天，我来讲讲其中的科学原理。

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."

   答案要从一种叫辣椒素的化学物质说起。它就是辣椒里产生那种火辣“灼烧感”的物质。

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!"

   我们的神经上有一些微小的感受器，叫作受体。其中一种叫TRPV1，通常会对热到让人疼痛的温度产生反应。它被激活时，会向大脑发出一个信号：“好烫！”

   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.

   巧妙的地方就在这里。即使没有任何真正的热量，辣椒素也能激活同一个TRPV1感受器。所以当你吃辣椒时，你的大脑收到的信息就和你的嘴被烫到时一样。

   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.

   这个感受器是科学家戴维·朱利叶斯发现的，他正是利用辣椒素找到了它。2021年，他因发现温度和触觉的受体而共同获得了诺贝尔生理学或医学奖。

   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.

   这也解释了一个常见的误区。很多人在食物太辣的时候会喝水，但辣椒素不太溶于水，所以灼烧感往往还会持续。在我家，我们会吃一点米饭或面包。

   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.

   那么，我们为什么要吃一种让大脑以为自己在疼的东西呢？对很多人来说，这种灼烧感正是乐趣的一部分。它给食物增添了刺激和风味，而且在很多文化里，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.

   总结一下，辣椒其实并没有烫伤我们。它只是骗过了我们神经里的一个热感受器。下次你吃辣的东西时，你就会清楚地知道嘴里发生了什么。谢谢大家。