最常回放片段：卡路里摄入与消耗是个误区！为何多数节食计划失败——Jason Fung博士

在你书的第二部分，提到了卡路里的欺骗性。

In part two of your book, say the calorie deception.

是的。

Yeah.

你指出关于肥胖和减肥有五个错误假设。卡路里摄入与消耗是相互独立的，因此不会相互触发。还有一个关于基础代谢率稳定的有趣观点。是的。本质上是因为人们常会说‘我新陈代谢慢’。

And you say there are five wrong assumptions about obesity and weight loss. The calorie calorie calorie in calorie out are independent of each other, so won't trigger one another. And this interesting point about the basal metabolic rate being stable. Yeah. Is that in essence because people, you know, people will often say I have a low metabolism.

这有点像文化中的一种说法。如果有人肥胖，诊断往往是他们新陈代谢慢。这种说法有道理吗？是真的吗？

It's kind of like a word in culture. If someone is obese, often the diagnosis is they have a low metabolism. Is there any merit in that? Is that true?

哦，完全正确。问题是，当你考虑体脂时，你会想到能量平衡方程。体脂等于摄入卡路里减去消耗卡路里。这常让人说，只要少吃500卡路里，每周就能减掉一磅脂肪。这无疑是错误的，因为过去五十年我们做的每一项研究都表明，如果你少吃500卡路里，随着时间的推移，根据你吃的食物种类，你的身体最终只会少燃烧500卡路里。

Oh, absolutely. The question, so when you think about body fat, you think about the energy balance equation. Body fat equals calories in minus calories out. This often leads people to say, well, just eat 500 fewer calories and you'll lose a pound of fat per week. It's unquestionably false because every single study that we've done over the last fifty years shows that if you eat 500 fewer calories, then over time, depending on what foods you're eating, eventually your body will just burn 500 fewer calories.

这就是你的基础代谢率，即你身体一天消耗的卡路里数。我们在几乎每一项研究中都看到这一点。至少八十年前我们就知道这一点。你摄入的卡路里减少，身体燃烧的卡路里也会减少。这会限制你能减掉多少体重，对吧？

So that's your basal metabolic rate, the number of calories that your body is expending in one day. So we see this in almost every single study. We've known about it for like eighty years at least. You eat fewer calories, your body burns fewer calories. Well, that's going to limit how much weight you're going to lose, right?

所以‘只要少吃卡路里就会自动减肥’的想法是完全错误的，因为我们知道少吃卡路里也会导致少燃烧卡路里。你少吃500卡路里，身体少燃烧500卡路里，体重根本不会减少。

So this idea that just eat fewer calories will automatically lead to weight loss is completely false because we know that eating fewer calories leads also to burning fewer calories. So you eat 500 less, your body burns 500 less, and you're not losing any body weight.

比如说，我为了减肥开始节食。我的新陈代谢会降低以适应我给自己设定的热量限制。那么当我停止节食后会发生什么？我的新陈代谢会保持吗？

So I go on a diet, let's say, because I'm trying to lose weight. My metabolism lowers to meet the calorific restriction that I've imposed on myself. What then happens when I come off the diet? Does my metabolism stay

通常是的。这就是所谓的溜溜球节食效应。假设你原本摄入2000卡路里，消耗2000卡路里。这样你既不会增重也不会减重，对吧？现在你决定开始节食。

Generally yes. So that's that yo yo dieting effect. So say you start with 2,000 calories in, 2,000 calories out. You're not gaining weight, you're not losing weight, right? Now you decide, okay, I'm going to go on a diet.

于是你把摄入降到1500卡路里，想着能消耗2000卡路里，而500卡路里由体脂提供，对吧？这就是平衡等式的方式。但如果你吃错食物还不停进食，比如像人们建议的那样每天吃8-10顿，吃低脂高碳水食物，导致胰岛素飙升——胰岛素会阻止你燃烧体脂。明白吗？其实这个原理我们八十年前就知道了。

So you go down to 1,500 calories, thinking that you're going to burn 2,000 and the body fat's going to provide 500, right? That's how you balance that equation. However, if you eat the wrong foods and you're eating all the time, so you're eating 10 times a day, eight times a day, like people say you should, you're eating low fats, you're eating tons of carbs, you're spiking your insulin, insulin prevents you from burning body fat. Okay? So again, we've known about this for eighty years.

现在你摄入1500卡路里，但胰岛素水平居高不下。虽然热量减少了，但持续摄入高碳水食物让胰岛素保持高位。你摄入1500卡路里，身体需要消耗2000卡路里，却无法动用体脂储备。就像钱存在银行里但银行关门了，你取不出来。

So now you eat 1,500 calories, but you're keeping your insulin levels really high. So fewer calories, but lots of high carb foods, eating all the time, insulin stays high. You're taking in 1,500, your body is now burning 2,000, but you can't burn any body fat. So the calories that are stored in your body fat cannot be sort of taken out. It's like it's in the bank and the bank is closed, you can't take it out.

接下来会发生什么？等式无法平衡。由于胰岛素水平高，当你摄入1500卡路里时，身体只能消耗1500卡路里——你的代谢率瞬间下降了500卡路里。

So what's going to happen? Well, you don't have a balanced equation. So that cannot happen. So what happens is that in order to balance that equation, because your insulin levels are high, you're eating 1,500 calories coming in, your body can only burn 1,500 calories. Your metabolic rate has just now gone down by 500 calories.

结果呢？你一点体脂都没减掉。这就是'热量理论'完全错误的典型案例。如果持续这样，时间久了你会因为热量消耗不足而感到疲惫，连维持体温的能量都不够。

And guess what? You're not losing any body fat. So that's an example of how calories idea is completely wrong. Because if you continue to do that, what's going to happen over time is that you get tired because you're burning fewer calories. You don't have enough energy to generate body heat.

于是你感到寒冷、疲倦、饥饿，决定把摄入提高到1800卡路里。现在你吃1800卡路里却只消耗1500卡路里——猜猜会怎样？你反而胖了。你会困惑：这怎么可能？

So you're cold, you're tired, you're hungry, you so say, okay, I'm going to go to 1,800 calories. So now you're eating 1,800 calories, but you're only burning 1,500 calories. Guess what? You gain weight. And you say, but how can I gain weight?

我现在吃得比以前少了。没错，你确实比过去摄入2000卡路里时要少，现在只吃1800卡，但你吃错了食物——那些胰岛素指数极高的食物。所以结果你反而会增重。实际上大家都这么说，但所有营养师和医生就是不相信。

I'm eating less than I did. Yes, you are eating less than the 2,000 calories you used to You're eating 1,800, but you're eating the wrong foods, very high insulin foods. So therefore you're going to gain weight. In fact, everybody says that. And all nutritionists, all the doctors, they just don't believe them.

他们说你撒谎、作弊，实际吃得比你以为的要多。

They say, you're lying, you're cheating, you're eating more than you think.

这就解释了我朋友身上一直让我困惑的事。他坚信'摄入消耗热量平衡'理论，我提过他几次，他也在网上发相关内容。实际上他确实练出了接近六块腹肌的身材。

So this explains something that happened with one of my friends, which always puzzled me. He swears by the calories in, calorie out thing. I've spoken about him a few times. He posts about it online as well. And he he actually managed to get a pretty much like six pack abs, pretty much.

当时他经常吃达美乐披萨，很多很多披萨。我总在想：这家伙怎么能边吃这么多披萨边实践热量平衡？后来他停止吃披萨后...没错，就出现了溜溜球效应。

And at the time, it appears that he was eating a lot of Domino's pizzas. A lot of pizzas. And I was thinking, how is this guy eating all these pizzas but he's using this calories in, calorie out thing? And then when the pizza stopped Yeah. There was this yo yo effect

是啊。

Yeah.

他达到了我所说的六块腹肌或接近的状态，然后突然停止节食，就出现了严重的溜溜球效应。我想这就是你说的——他降低了新陈代谢率，所以只要稍微多吃一点...

Where he managed to get to basically what I described as a six pack or there or thereabouts. And then stopped eating all stopped the diet per se, and then there was this big yo yo effect, which I imagine is what you said there. What he's done is he's lowered his metabolism. And then when he goes up just a little bit

就全反弹回来了。

It all comes back.

一切都会回来，甚至更多。

It all comes back and then some.

甚至更多。

And then some.

是的，绝对如此。这种节食方式长期来看反而会让你增重？

Yeah. Absolutely. This form of dieting is actually over the long term probably gonna make you gain weight?

哦，这非常有害。这就是所谓的溜溜球节食。我们都知道它非常有害。但换个角度想想。让我们用相同的卡路里举个不同的例子，这就是为什么我一直说你需要考虑的不仅仅是卡路里。

Oh, it's it's very detrimental. And that's what yo yo dieting. We all know it's very detrimental. But think about it differently. Let's take a different example with the same calories, which is why I keep saying you have to think about more than the calories.

你必须考虑激素的作用，因为那是给身体的指令。食物含有卡路里和能量，但它也包含关于如何处理的指令。举个例子，你摄入2000卡路里，消耗2000卡路里。现在你开始节食。

You have to think about what the hormones are because that's the instructions to your body. Food contains calories, energy, but it contains instructions as to what to do. So let's take an example. You're eating 2,000 calories in, 2,000 calories out. Now you go on a diet.

你摄入1500卡路里。但你同时进行间歇性断食。断食时，胰岛素水平会下降——这正是关键所在。胰岛素是一种进食时上升、不进食时下降的激素，对吧？

You take in 1,500. But what you do is you do some intermittent fasting. When you fast, insulin is going to fall. That's the whole point. Insulin is a hormone that goes up when you eat, it goes down when you don't eat, right?

所以当你进食时胰岛素上升，身体会储存能量；断食时胰岛素下降，身体会说'我没有能量输入，请从储备中调用'。现在你摄入1500卡路里但配合间歇性断食，让胰岛素水平下降。此时虽然摄入1500卡路里，但低胰岛素水平会让身体想要消耗2000卡路里——它会说'胰岛素水平低，让我从体脂中调用500卡路里'。

So when you eat, insulin goes up, your body wants to store energy. When you don't eat, insulin goes down, your body says, I have no energy, I have no food coming in, please take it out of storage. So now you take 1,500 calories, but you do intermittent fasting, you're allowing your insulin levels to fall. Now 1,500 calories are coming in, insulin levels are low, your body wants to burn 2,000 calories. It says, well insulin levels are low, let me take 500 calories from my body fat.

猜猜看，你从体脂肪中获取500卡路里，从食物中摄入1500卡路里，消耗2000卡路里。这是个平衡方程式。与相反情况不同，你会发现总热量是相同的。虽然摄入从2000降到1500，但关键在于你让胰岛素水平下降，从而能够燃烧体脂肪。这是荷尔蒙发出的信号：请释放能量，打开通道让体脂肪得以代谢。

Guess what, you have 500 coming from your body fat, you have 1,500 coming from your foods, you burn 2,000. It's a balanced equation. So instead of the opposite situation, and you see that the calories are the same. You went from 2,000 in to 1,500 in, but what the difference was, you allowed insulin to fall, which allowed you to burn body fat. It's the hormonal signal that says, please take energy out, open up the doors so that body fat can come out.

而这正是人们缺失的关键认知——大家总说'我是这样'、'我是那样'。但为什么无法燃烧身上的脂肪呢？明明体内储存着二三十万卡路里的脂肪。为什么无法调用？因为你没有激活正确的荷尔蒙来获取这些能量。

And this is the piece that's missing because people are all like, well, I'm this, I'm that. And it's like, well, why can't you burn the fat that's on your body? Because there's 200, 300, thousand calories of body fat. Why can't you access it? It's because you haven't activated the right hormones so that you can access it.

所以现在如果你进行间歇性断食，摄入1500卡路里，调用500卡路里储备，身体总共消耗2000卡路里。突然某天你停止节食，恢复2000卡路里摄入会怎样？体重既不增也不减，和从前一样。但若降到1800卡路里，体重就会下降。

So now if you do intermittent fasting, you eat 1,500 calories, you take 500 calories out, your body's burning 2,000. Now all of a sudden, if you go off your diet and you go back to 2,000 calories, guess what? You don't gain weight, you don't lose weight. Same as before. Whereas before you go even to 1,800 calories, you lost weight.

但真正的差异不在卡路里数值（始终是2000对500），而在于你开始关注身体接收的荷尔蒙信号——胰岛素是主要调控激素，当然还有皮质醇等其他重要激素。

But the difference was, not the calories, it was always 2,000 to 500. The difference was you paid attention to the hormones that you're telling your body, and the insulin is sort of the primary hormone. There's actually a lot more. Cortisol is very important hormone, there's other hormones.

你提到卡路里消耗的问题。关于'卡路里进出'模型有个观点认为：通过运动消耗一千卡路里，就能为自己创造额外进食的空间。

You mentioned burning calories there. One of the thoughts around the calories in calories out model is that you can just exercise and if you burn a thousand calories exercising then that gives you a little bit of a reserve there to eat more for example.

确实如此，不过这个效果其实微乎其微。运动当然对健康大有裨益：增强柔韧性、力量、核心肌群等等，非常重要。但对减重而言效果极其有限。为什么呢？

Yeah and it's probably a very, very small effect for a couple of reasons. So we know that if you exercise, and I say this exercise is really good for you in a number of ways: Flexibility, strength, core, all kinds of things. So very, very important. But in terms of weight loss, it's actually a very, very small effect. Why?

首先，运动消耗的热量本就不高。假设进行八小时高强度训练确实能燃烧大量卡路里，但我的服务对象多是中年以上人群——他们通常每周快走三次，每次半小时左右。如果你留意过跑步机上的卡路里计数器就会发现，数字增长极其缓慢。半小时运动可能只消耗120卡路里左右。

Because one, the amount of calories you burn during exercise are simply not that high. So if you look at, you know, if you do walking, I mean, if you did eight hours of high intensity exercise, yeah, you're going to burn a lot of calories. But most people I deal with, which are sort of middle aged and higher, you're talking about sort of a quick walk or, you know, 45, half an hour, three times a week sort of thing. And if you ever go on the treadmill and you ever watch that calorie counter on the treadmill, you know, it goes up very, very slowly, right? You'll do half an hour and it'll be up to like 120 calories or something like that, right?

所以那次运动其实没消耗多少卡路里，大概就相当于几块饼干的热量，对吧？从数字上看确实很少。假设你身体正常消耗2000卡路里，包括大脑产热、心肺肝脏等器官运作，现在增加到2100卡路里，按比例来说影响不大。运动另一个问题是它反而容易让人吃得更多。

So that exercise really didn't burn off very many calories, it's the amount that you'd get in a couple of cookies, for example, right? So numerically, it's just very small. So if your body is normally using 2,000 calories with your brain generating body heat, your heart, your lungs, your liver, they're using 2,000 calories and now you go up to 2,100 calories. Well, percentage wise, it's not a huge deal, right? The other problem with exercise is that it tends to actually cause you to eat more.

这个问题我们已经研究了几十年。运动过程中食欲会降低，这种现象称为运动性厌食症。比如打篮球时你不会突然觉得饿，因为血液都流向肌肉了。

So again, we've had decades of study for this. If you exercise, during the exercise, you have reduced appetite. So you have, it's called exercise induced anorexia. So in the middle of a basketball game, you don't suddenly go, Oh, wow, I'm really hungry, right? Because your blood is flowing in your muscles and so on.

运动时确实不会感到饥饿，但之后会出现反弹。研究发现人们运动后反而更饿，这种饥饿感容易导致增重。哈佛大学几年前有个有趣的研究，测量了儿童在不同活动中的热量差异。

You're not thinking about the hunger. So hunger actually goes down during exercise, but after exercise, we see this rebound. So we see that people are actually more hungry after exercise. And if you're hungrier after exercise, it's going to cause you to tend to gain more weight. In fact, there's this very interesting study that was done a few years ago in Harvard where they measured the sort of calorie difference that you get for children in certain activities.

研究发现，儿童看电视时每小时平均多摄入100卡路里——坐着不动确实容易发胖。而轻度运动的热量消耗也差不多。

So they said, okay, what if a child is watching TV, what's the average caloric difference? And it was like plus 100 calories per hour. So for every hour of TV, they're sort of positive 100 calories over time. And that makes sense, you're just sitting there. When you look at mild exercise, it's about the same.

同样是正100卡路里左右，唯一解释就是运动刺激了食欲。为什么吃得更多？因为运动引发的饥饿感会让你摄入更多热量，这反而让减肥变得困难。

It's about positive 100 calories. So the only way that happens is that if that exercise is causing you to eat more, right? And you say, well, why are you eating more? It's like, well, because you're hungry. The exercise is inducing you to eat more, and that's gonna make it difficult to lose weight.

你在第四章提到95%的减重效果取决于饮食。

You say in the book in chapter four that 95% of weight loss is diet.

没错，这就是为什么单靠运动很难减肥。当然不是说不该运动，每个人都应该运动。但想减肥的话，重点还是要放在饮食上——不仅是热量控制，食物种类会影响荷尔蒙平衡，进食频率也很重要。不停进食和间歇性禁食带来的荷尔蒙变化对体重影响截然不同。

Yeah, and that's the reason why exercise, it's very hard to exercise enough to lose weight. And that's not to say that you shouldn't exercise, you really should exercise, everybody should exercise. But if you're trying to lose weight, you still got to focus on the main topic, which is the foods that you eat, which is not just the calories, it's about the types of food that you eat, which is going to affect the hormonal balance and also how often you eat. If you're eating all the time versus if you're only eating very infrequently, then you're going to have a different hormonal balance that is going to affect your weight as well.

一项针对6万多名美国成年人和儿童的调查显示，1977年大多数人每天进食三餐。而到2003年，大多数人每天要吃五到六餐。

An American survey of more than 60,000 adults and children revealed that in 1977, most people ate three times a day. By 2003, most people were eating five to six times a day.

没错。这正是那种全天候进食的理念。我觉得这现象很耐人寻味，因为这种饮食变化是在我们毫无察觉中发生的，却从未被讨论过。1977年时，我们还提倡人们多吃碳水化合物。

Yeah. Yeah. This is the whole idea of sort of eating all the time. And this I find fascinating because it was this sort of inadvertent change in our diet that we never talked about. So in 1977, we told people eat lots of carbs.

这些都有文献记载。当时美国政府明确建议碳水摄入要占55%-60%，减少脂肪摄入。实际情况是，1977年人们只吃早午晚三餐，没有零食。想放学后吃零食？妈妈会说'不行，会影响晚饭'。睡前想吃点心？妈妈会说'晚饭时你就该多吃点'。

So we know that, that's in print. For sure, the American government said eat 55 to 60% carbs, eat less fat. What happened is that, you know, in 1977, people ate breakfast, lunch and dinner, no snacks. If you wanted an after school snack, your mom said, No, you're going to ruin your dinner. If you wanted a bedtime snack, your mom would say, No, you should have ate more at dinner.

问题在于，当我们开始大量摄入碳水后，情况就正如之前讨论的：早上吃两片果酱面包根本不会产生饱腹感，胰岛素和血糖会急剧飙升又骤降。

No problem. But what happened is that as we started to eat sort of a lot of carbs, what happened is exactly as what we discussed before, you eat two slices of bread in the morning with jam, you have no satiety, insulin spikes way up, glucose spikes way up, but then it crashes.

于是你又饿了。

So you get hungry again.

到上午10点半你就会饿，然后去找低脂松饼吃。这是因为血糖和胰岛素水平都在下降。现在你有了上午加餐，中午吃大盘意面后，下午3点又会饿得发慌，接着去找饼干之类的零食，对吧？

Then you get hungry at 10:30. So you go around looking for a low fat muffin. And it was because your sugars are going down, your insulin's going down. So now you're eating mid morning snack, then you eat a big plate of pasta, then you get ravenous at like 03:00. So you go find yourself some crackers or something like that, right?

就这样，上午加餐、下午茶点、睡前零食都出现了。到2003年，普通美国人每天要吃五到六顿。但他们还觉得'看我吃得多低脂，这肯定是正确的饮食方式，肯定对健康有益'。

And then now you're having a mid morning snack, you're having mid afternoon snack, then you're having a bedtime snack. And that's the average American by 2003 is eating five, six times a day. But they're saying, hey, I'm eating so low fat. This must be the right way to eat. This must be good for me.

于是现在吃零食变成了一种制度化的行为，而1977年之前的零食只是偶尔的放纵。对吧？这对你并不好。它对你是有害的，但嘿，偶尔放纵一下也无妨。然后它就变成了我们每个人都应该做的事情。

So now the snacking becomes institutionalized, whereas pre 1977 snacks are an indulgence. Right? It's not something good for you. It's something bad for you, but hey, once in a while you indulge. Then it becomes institutionalized as something that every single one of us should be doing.

我们绝不应该超过一个半小时不进食。让我们简单思考一下：当你进食时，胰岛素会上升，身体会储存热量，因为你告诉它这么做。如果你不吃东西，或者禁食，你的胰岛素会下降，身体会将这些储存的热量重新释放出来，对吧？这样你就会燃烧热量。

And we should never be without food for more than an hour and a half. Let's think about this very simply. So if you eat, your insulin is going go up, your body is going to store calories because you told it to. If you don't eat, or if you fast, your body is, your insulin is going to go down, you're going to bring those calories back out of storage, right? So you're going to burn calories.

你吃东西就储存热量，不吃东西就燃烧热量。非常简单。那你为什么想要一直吃东西呢？这完全没有道理。如果你想减掉体脂，实际上需要延长不进食的时间。

You eat, you store calories, you don't eat, you burn calories. Very simple. So why would you want to eat all the time? That makes no sense at all. If you want to lose body fat, you actually need to extend the period of time that you're not eating.

换句话说，延长你的禁食时间并戒掉所有零食，这样你才有足够的时间让胰岛素保持低水平。当胰岛素低时，就会促进脂肪燃烧，让你能够调动那些储存的热量。

In other words, extend your fasting period and get rid of all the snacks in order for you to have enough time that your insulin is low. When insulin is low, it's going to allow fat burning, which is going to allow you to pull those calories back out.

你被称为现代间歇性禁食的真正创始人。我在这个节目上听人们一遍又一遍地谈论间歇性禁食，但互联网上说这个概念确实源自你。要知道间歇性禁食已经存在数千年了，但将其作为减肥工具的理念，据说是因为...

You're cited as being really the founder of modern intermittent fasting. I've heard people talk about intermittent fasting on this show over and over and over and over again now, but the Internet says that it really came from you. Know that intermittent fasting has been happening for thousands of years, but the idea of it as a tool for weight loss, they say it came Because from

在2013、2014年时，真的没有人从医学角度讨论这个问题。比如：身体会发生什么变化？为什么它有益？为什么有害？而多年来，我就像荒野中的独行者，一直在说：嘿，这对我们是个好工具。

in 2013, 2014, really nobody was talking about it from a medical standpoint. Like, what's happening in the body? Why is it good? Why is it bad? And really, I was, for years sort of this one voice in the wilderness that was saying like, Hey, this is a tool for us.

如果减肥对你很重要，那么你完全可以划出一段时间不进食。当时人们认为这对你非常有害。我查阅了所有文献后说：为什么它有害呢？他们给出了各种理由。关于间歇性禁食有很多误解，说它会导致体重增加、疲劳、饥饿等等。

If you want to lose weight because it's important, then you can just set aside a period of time that you don't eat. At the time, people thought it was extremely bad for you. And I looked through all the literature and I said, Well, why is it bad for you? And they had all these reasons. There's all these myths about intermittent fasting and how it's going to cause you to gain weight and be tired and hungry and all these things.

我说，不，实际上过去两千年来我们使用间歇性断食的数据非常多，而这些说法根本不成立。我可以列举其中一些例子，但正因如此当时没人讨论这个话题，而我开始将其引入公众视野，让大家意识到这只是一种工具。仅此而已。你当时

I said, Well, no, there's actually a lot of data here over the last two thousand years that we've used intermittent fasting and they're simply not true. And I can go over a few of those, but that's why there was nobody talking about it at the time and that's where I started to sort of bring it into the sort of public consciousness that this is a tool. That's all it is. Were you

因为这个受到攻击了吗？

attacked for that at the time?

哦，当然。我遭到各方抨击。医生们追着我批评，营养师们也紧咬不放。所有人都认为我会造成巨大危害。但有趣的是，当我回想起来，很多同行私下对我说：知道吗？

Oh, absolutely. I got attacked from all sides. Doctors were coming after me, dieticians were coming after me. Everybody thought I was going to do so much harm. And the funny part was that, as I think back, as I spoke to a lot of colleagues, a lot of colleagues would say to me, You know what?

我在培训期间就经常这么做。我们总是不间断地工作24小时不吃东西，因为要待在手术室或急诊室，忙得不可开交。我们一直这样也没出问题。我记得当时就想：知道吗？

I used to do that when I was in training. We did that all the time. We'd go twenty four hours without eating because we're in the OR, or we're in the ER, or we are busy. So we did that constantly and nothing bad happened. And I remember thinking, You know what?

作为医生，我其实经常要求人们禁食。要做手术需要禁食，术后需要禁食，做空腹验血也要禁食。那为什么我总在要求人们禁食，可到了减肥时却被告知不该断食呢？

As a doctor, I actually tell people to fast all the time. If you have to go for surgery, you need to fast. If you're after surgery, you need to fast. If you do fasting blood work, you need to fast. So why is it that I'm actually telling people to fast all the time, and yet for weight loss, you shouldn't fast?

这完全说不通。从人体生理学角度根本解释不通。有人提出的观点是：断食会让你之后吃得更多、更饥饿，基础代谢率会下降。

That doesn't make any sense. Physiologically from a body standpoint, it doesn't make any sense. One of the things people talked about was, it's going to make you eat more later. It's going to make you more hungry. Your basal metabolic rate's going to go down.

这是关于间歇性断食的最大谬论之一——说它会引发所谓的'饥饿模式'，对吧？这种理论认为你的基础代谢率会降到极低，一旦恢复进食就会复胖。于是我说：让我们做个实验，找个人比如你，禁食四天测量热量消耗，在禁食前测基础代谢率，禁食四天后再测。假设第零天每天消耗2000卡路里。

This was one of the big myths of intermittent fasting, that's going to cause the so called starvation mode, right? And this is the idea that your basal metabolic rate will fall so low that when you do start to eat, you're going to gain weight again. So I said, well, let's think about this. You can do a study where you take somebody, say you, for example, and you could fast them for four days and measure how much, how many calories they're burning, their basal metabolic rate on day zero before the fast and measure them four days into the fast and see how many calories you're burning. So on day zero, they say you're burning say 2,000 calories a day.

在禁食的第四天，你连续四天不进食任何食物，他们测量你燃烧的卡路里量，你的身体正在燃烧2200卡路里。你的基础代谢率不仅没有下降，反而上升了。禁食期间，你的身体正在自我激活。这非常有趣，因为如果你想减肥，基础代谢率下降就意味着失败。一旦代谢率下降，减肥就会变得极其困难。

On day four of zero food, you don't eat any food for four days, they measure how much calories you're burning, your body is burning 2,200 calories. Your basal metabolic rate didn't go down, it went up. Your body is activating itself during fasting. Which is fascinating because if you're trying to lose weight, dropping that basal metabolic rate is death. If you drop that metabolic rate, it's so hard to lose weight.

这正是限制卡路里饮食和低脂饮食的弊端，也是频繁进食的后果。但当你真正禁食时，代谢率反而会上升。我们在一个又一个研究中都观察到了这种现象。其原因其实源于基础生理学原理。

That's what the calorie restricted diets did. That's what the low fat diets did, the eating all the time did. But when you actually fast, your metabolic rate went up. And we see this in study after study. And the reason is actually basic physiology.

这实际上是医学生理学知识，属于医学院一年级的内容。当你停止进食时，从激素角度来看，体内会发生以下变化：胰岛素水平下降，身体开始动用储存的卡路里。与此同时，其他激素水平上升——交感神经张力增强（即战斗或逃跑反应），皮质醇水平因身体激活而升高，生长激素分泌也会增加。

It's actually medical physiology, like first year medical school stuff. When you don't eat, what happens in your body from a hormone standpoint is that your insulin's going to fall, you're going to allow your body to start using the calories that are in the body. At the same time, other hormones go up. So the sympathetic tone goes up, which is your fight or flight response. Your cortisol levels go up because again, it's an activation and your growth hormone goes up.

因为这些激素会促使身体开始调用储存能量。实际上你正在激活自身机能。想象野外场景：看到饥饿的狼时，它会显得萎靡不振吗？不，它反而更加警觉。比起刚饱餐的狮子，饥饿的狼其实更危险——因为吃饱后你只想躺着不动。

Because those hormones are going to start telling your body to start pulling calories out. So you're actually activating yourself. Think about in the wild, if you see a hungry wolf, is that wolf just sort of, you know, all like lethargic? No, he's activated. He's actually more dangerous than any other wolf as opposed to say a lion who just ate, because when you just eat, you just want to lie there.

你需要消化食物，这时会感到精力不济。所以人们常说禁食会降低代谢率，但事实恰恰相反。

You want to digest your food. You have no energy. So people say, wow, your your your metabolic rate's gonna go down if you fast. No. The the truth is actually the opposite.

代谢率会上升。

It goes up.

你的观点让我开始把食物视为对身体的一种指令——如果我吃这种食物，就会对激素产生特定影响，进而影响身体状态。既然我们把食物看作身体指令，之前讨论过进食时间和禁食话题。我想更深入探讨这点。关于早餐，我读到你认为大多数人其实不需要吃早餐。

You've got me thinking about food as an instruction I'm giving my body because if I eat this food, it's gonna have this impact to my hormones, which is gonna have this impact on my body. So if we view food as an instruction to the body, we talked a little bit about the timings of eating and a little bit about fasting. I wanna get into that a little bit more. But breakfast. I read that you didn't think most people need breakfast.

是的。那种认为一起床就必须立刻吃东西的观念完全是错误的。关于早餐这件事，其实你总是在打破禁食状态。想想这个词的字面意思。

Yeah. The the whole idea that you need to eat as soon as you get up is just false. So there's this whole thing about breakfast. Now you will always break your fast. Think about the actual word.

对吧？Break fast（打破禁食）。这是结束你禁食状态的一餐，这说明在英语中我们默认人体每天应该有个禁食期。为什么？因为本就应该有段进食期——你吃东西，胰岛素上升，储存热量。

Right? Break fast. It's the meal that breaks your fast, which tells you that in the English language, we accept that your body should have a fasting period every day. Why? There's a period of time that you're supposed to feed, you eat, insulin goes up, you store calories.

然后还应该有段禁食期——从晚餐后到次日早餐前，对吧？假设你晚上6点停止进食，早上8点吃早餐，这14小时里身体没有进食而是在禁食，因此会消耗热量，明白吗？但'早餐'这个词告诉我们这其实是正常循环模式：进食期后接禁食期。如果你不停进食，身体就只会储存能量而永远没机会燃烧能量。

Then there's supposed to be a period of time that you fast, that's after dinner until the next day's meal, which is breakfast, right? So say you stop eating at 6PM, you eat at 8AM, that's a fourteen hour period where your body is not eating, it's fasting, and therefore it's going to use calories, right? But the word breakfast tells us that that's actually a normal pattern, this normal cyclical pattern. You feed, then you fast, right? If you eat all the time, your body's just gonna store energy and never have a period to burn energy.

那么结果会怎样？你会发胖。

So okay. Well, what's gonna happen? You're gonna gain weight.

您刚才听到的是往期节目中最常被回放的片段。如果想收听完整内容，我已将链接放在下方说明栏里。感谢收听。

What you just listened to was a most replayed moment from a previous episode. If you wanna listen to that full episode, I've linked it down below. Check the description. Thank you.