RFK Jr. 如何操控营养研究 | 凯文·霍尔

极低碳水。

Ultra low carb.

所以生酮饮食中脂肪占80%，整个过程中保持蛋白质摄入量不变。

So ketogenic diet is 80% fat, kept protein intake constant the whole way along.

在那里，我们的主要目标是：当你采用这种极低碳水饮食时，我们能否观察到代谢优势——即阿特金斯自20世纪70年代初以来所倡导的热量消耗增加，也就是所谓的代谢优势。

And there we were really, the main outcome was, okay, you went to this very low carb diet, could we see this metabolic advantage, the increase in calorie burn that Atkins has promoted since the early 1970s, the so called metabolic advantage.

因此，我们让这些受试者在第一个月内遵循这种适应期饮食。

And so what we did was we had these folks for the first month on this run-in diet.

他们正在减重，这最终成为一种批评点。

They were losing weight, which ended up being a little bit of a critique.

我们没能让他们保持体重稳定，我们曾早期讨论过是否应该增加热量摄入，以及是否需要延长适应期的持续时间。

We weren't able to kind of keep them in weight maintenance, and we sort of had early discussions of should we increase the number of calories, and then do we have to extend the duration of the run-in diet?

所以我们决定保持热量恒定，观察体重变化速率和体脂变化速率是否发生改变，并在数据分析中对此进行调整。

So we decided, let's just keep calories constant and we can see if the rate of weight change is altered, the rate of body fat change is altered, and we'll try to adjust for this in the data.

所以，这同样不是一个完美的研究。

So again, not a perfect study.

在第一个月之后，我们让这些人进入呼吸舱连续两天，测量他们消耗的总热量。

And then after that first month, we said, okay, we're gonna put these folks in these respiratory chambers for two continuous days and measure the total number of calories they burn.

在进行一个月的生酮饮食后，我们会再次让他们进入呼吸舱连续两天。

And then after a month of this ketogenic diet, we'll do the same thing, put them in the respiratory chamber for two continuous days.

如果我们设计的研究能够检测出每天150大卡的差异，因为我们的模型预测效率上的差异会略低于这个数值。

And if we powered the study to detect a difference of 150 calories a day, because our model suggested that there would be some differences in efficiency amounting to a little bit less than that.

因此，我们想看看是否存在超出预期的额外益处。

And so we wanted to see if there was any additional benefit, more than was expected.

结果发现，我们并没有看到这种差异。

And lo and behold, we didn't see it.

我们实际上

We actually

特别是在脂肪减少方面。

In fat loss specifically.

不，这是指能量消耗和热量消耗。

No, this was in energy expenditure, calorie expenditure.

所以，无论进行如此巨大的饮食切换，他们燃烧的卡路里数量都基本相同。

So they were burning more or less the same number of calories regardless of this huge swap.

你当时是计算那些减重的人的卡路里消耗减少情况吧

And you were calculating for those who lost weight to decrease

是的，如果我们对此进行调整，结果仍然只是非常非常小的差异，远低于每天150卡路里。

the Yeah, so if we adjusted for that, yeah, it still was a very, very tiny amount, much less than 150 calories per day.

但我没提到的是，我们实际上让参与者每周都在呼吸舱里待两天。

But then what I didn't mention is we actually had people in those respiratory chambers every week for two days.

当我们早期观察时，确实看到了更大的效果。

And when we looked early on, we actually saw a bigger effect.

在睡眠期间，差异最高达到了大约每天100卡路里，但到了实验后期，这种效果逐渐减弱，到了最后几天，这种差异已经消失了。

It went up to, I think, about 100 calories a day difference during sleep, And then it kind of petered out by the end of the experiment so that when we looked on those final days, that effect had dissipated.

但早期确实发生了一些事情，我们至今仍未能完全理解。

But something happened early on, which we still don't really fully understand.

我对这可能是什么有一些假设，但这些都只是假设而已。

I have some hypotheses about what that might be, but those are just that.

所以看起来，在早期阶段你会看到一些现象，但在后期阶段就没有了。

And so it seemed like the early phase you would see something, not the later phase.

因此，关于没有等待足够长时间的批评似乎站不住脚。

So the criticism about not waiting long enough didn't seem to hold up.

它消失了。

As it went away.

它随着时间推移逐渐消失了。

As it went away over time.

但当然，你可能会说，哦，如果研究不是两个月，而是三个月或六个月，也许它又会回升。

But then of course you could say that, Oh, maybe it'll go back up again if you did instead of a two month study, a three month or a six month.

当然，这种情况可能发生，但我不知道有任何理由怀疑它会真的发生。

Of course that might happen, but I don't know that there's any reason to suspect that it might happen.

另一个有趣的现象是，当我们使用另一种测量热量消耗的方法——即双标水法——时，当时确实检测到了一个信号，大约是每天150卡路里。

The other thing that was interesting was that when we used another method to measure calorie expenditure, something called the doubly labeled water method, at the time, it actually did seem to detect a signal and it was about 150 calories a day.

但这种方法并不是我们研究设计的基础，而且它的噪声要大得多。

But that's not how we powered the study and that method has a lot more noise with it.

当时我们并不理解这一点，所以我们实际上发表了这些数据。

And we didn't understand it at the time, so we actually we published that data.

我们说，这并不是主要结果，但看起来挺有意思的。

We said, that wasn't the primary outcome, but it looks kinda interesting.

后来我们才意识到，对于双标水法的计算，当我们对低碳饮食做出错误假设时，实际上会高估能量消耗。

And it was actually only later that we realized that the calculations for the doubly labeled water method, we actually they overestimate calorie expenditure when you make the wrong assumptions about low carb diets.

明白了。

Got it.

当我们后来在另一篇论文中修正了这些假设后，结果就与呼吸室的数据一致了，这让我们开始理解其中的逻辑。

And so when we were able to correct those assumptions in a later paper, we actually brought them in line with the respiratory chamber and that sort of started to make sense to us.

为什么关注点从减脂转向了能量消耗？

Why was there a shift from focusing on fat loss to energy expenditure?

因为

Because

在这个特定研究中，我们更容易测量它，而且当时人们也更多地在讨论这个问题，他们说我们在呼吸室中测量的能量消耗具有更小的置信区间。

we could measure it easier in this particular study, And it was also something that people were talking a lot more about at that time, was they said that the calorie expenditure that we could measure in a respiratory chamber has a much tighter confidence interval.

比体脂测量精确得多。

Much more precise measurement than body fat.

这也是人们提出过的另一种机制。

And that was another mechanism by which people had proposed.

体脂减少？

The body fat loss?

没错。

Exactly.

如果你在后期显著提高了能量消耗，那么当然可以推算出在更长时间内体脂减少会有怎样的意义。

If you increased energy expenditure enough by a later time point, then of course you could maybe extrapolate to how much body fat loss would be meaningful over a longer period of time.

我之前没提到的是，在这项研究中，我提到过人们在标准高糖、典型的美国饮食期间体重下降，体脂也略有减少。

And what I didn't mention is that in that study, I mentioned that people were losing weight and losing a little bit of body fat during the standard high sugar, standard American diet.

当我们把他们转为生酮饮食的最初几周，他们的体脂减少速度实际上略微放缓，之后又重新加快。

When we switched them to the ketogenic diet in that first couple weeks, they actually slowed down the rate of body fat loss just slightly, and then it picked back up again.

所以在每个饮食阶段为期一个月的两个周期内，他们实际上在高碳水、高糖饮食期间减掉的体脂比生酮饮食期间更多。

So that over both two week periods sorry, one month periods on each of those diets, they were actually losing more body fat on the higher carb, higher sugar diet than they were on the ketogenic diet.

再次强调，这些微小的差异毫无意义，而且这些数字的不确定性非常大，但这恰恰再次表明，人体并非完全完美。

Now again, meaningless small differences and the uncertainty around those numbers is quite large, But it just kind of shows again that the body isn't completely perfect.

你不必完全坚持‘热量就是热量’的观点，只要足够好就行。

You don't have to completely be a calorie is a calorie, it just has to be good enough.

这正是进化的运作方式。

And that's kind of how evolution works.

这种情况发生是有充分原因的。

And there's a really good reason why this happens.

因为作为人类，你永远无法确定自己吃的是什么。

Because as humans, you never know what you're eating.

没错，人类在全球各地、在各种不同的饮食模式下都取得了成功。

Exactly, and humans have been successful all over the planet on a wide range of different diets.

如果你在一次大型狩猎后——那种类似纯肉食的饮食——无法储存脂肪，那将会是个大问题。

If you couldn't store fat after a big game hunt, what was like a carnivore type diet, that would be a big problem.

对吧？

Right?

当然，当你摄入热量过剩时，身体会具备储存脂肪的机制。

So of course, you have mechanisms to store body fat when you're in caloric excess.

但当你考虑到这些摄入的热量时，它与高碳水饮食在很大程度上是等效的。

But and and it's more or less equivalent when you account for those incoming calories to a higher carb diet.

但在这些人为设计的研究中，你可以发现一些细微的差异。

But there are slight differences that you can pick up in these kind of contrived studies.

而这正是我们感兴趣并想深入探讨的地方。

And that's kind of what we were interested in delving into.

我很好奇，现在回过头来看，你觉得这会不会只是我的一个假设——即批评者以某种方式引导了你的研究，而这种引导可能并非你原本会采取的方向？

I'm curious, looking back at it now, do you feel like this could be just an assumption on my end, that the critics were guiding your research in a way that perhaps you wouldn't have guided otherwise?

是的，但我

Yeah, but I

我认为这是件好事。

think that's a good thing.

我认为当批评者提出合理观点时，你必须认真倾听。

I think that you have to listen to critics when they're making sensible things.

在这种情况下，你觉得这些批评是合理的吗？

Do you feel like it was sensible in that case?

是的，是的。

Yeah, yeah.

我觉得他们有些评论有点过头了，我并不一定认同。

Think of them went a little over the top with some comments here and there, which I didn't necessarily appreciate.

有些评论我觉得并不合理。

Some of the comments I didn't think were reasonable.

是的，作为科学家，不能假装自己设计出了完美的研究。

Yeah, think as a scientist, can't pretend that you've designed the perfect study.

即使这项研究，就像我说的，也存在一些合理的批评，比如他们整个过程中都在减重，如果他们处于增重状态又会怎样？

And even that study, like I said, there's legitimate criticisms that they were losing weight the entire time, what would have happened if they'd been in a state of weight gain.

那些谈论碳水化合物-胰岛素肥胖模型的人会说，我们关心的是导致脂肪增加的原因，而不是最影响脂肪减少的因素。

The folks who talk about the carbohydrate insulin model of obesity will say, we're interested in what causes body fat gain, not what most influences body fat loss.

因为这两者并不一定相同。

Because those don't have to be the same thing.

仅仅因为你能用药物治疗某种疾病，并不意味着这种疾病是由该药物缺乏引起的。

Just because you're able to treat something with a drug doesn't mean that they had that disease because of a deficiency of the drug.

对吧？

Right?

治疗方法不一定要和病因相同。

The treatment doesn't have to be the same as the cause.

所以我认为这也是一个合理的批评。

And so I think that's also a legitimate criticism.

对吧？

Right?

如果你要讨论肥胖的原因，这真的能说明什么吗？

If you're gonna talk about causes of obesity, does this really have something to say about?

我认为它确实能说明一些问题，但我认为一个合理的批评是，我们确实没有在过量喂养实验中测量过人群。

I think it does have something to say, but I think it's a legitimate criticism that, yeah, we haven't measured people in overfeeding experiments.

其他人做过，并且认为这实际上并没有太多支持这一理论的证据，但我们没有进行这些研究。

Other people have and suggest that it actually doesn't, there's not much support for that theory, but we didn't do those studies.

对。

Right.

你在这项研究中还看到其他关于人体生物标志物的变化吗？

Do you see any other changes in this research in people's biomarkers?

你们有没有关注其他非主要结果的变量？

Were you looking at any other variables as not the primary outcome?

哦，是的，因为我们从这些人身上获得了大量数据，我们测量了他们的很多指标。

Oh yeah, because we have this wealth of information from these people, we measure so many things on them.

我认为另一件重要的事是，人们进行这些饮食调整不仅仅是为了减重和减少体脂，还有各种各样的原因。

And I think that's another thing that's important, is that people go on these diets not just to lose weight and lose body fat, but for all sorts of reasons.

我的意思是，这可能是大多数人选择这类饮食的主要原因。

I mean, that's probably a main reason that many of them go on these kinds of diets.

有些人觉得非常有效，有些人则不然。

And some people find it really beneficial and some people don't.

而且，again，取决于你和谁交谈，以及他们属于哪个群体，他们往往会认为其他群体的观点是错误的。

And again, depending on who you're talking to and what sort of tribe they're in, they'll tend to generalize to the other tribe as being misguided in some way.

但确实，有很多事情都在发生。

But yeah, so there's all sorts of things that happen.

我的意思是，在这项研究中，当我们把碳水化合物摄入量降到极低水平时，胰岛素分泌减少了50%，这意味着人们在生酮饮食下所需的胰岛素比在高碳水、高糖饮食下要少得多，而这又是一个推论，已有其他研究观察过2型糖尿病患者的情况。

I mean, one of the things that was really interesting in that study when we got to these very, very low carbohydrate levels is that insulin secretion goes down by 50%, meaning that people don't require as much insulin to manage their glucose levels on a ketogenic diet as they did on the higher carb, higher sugar diet, which isn't And that again, it's an extrapolation, and there's been other studies that have looked at people with type two diabetes.

当他们坚持这些极低碳水的生酮饮食时，许多人不再需要外源性胰岛素，或者至少有很大一部分人不需要。

They don't need exogenous insulin anymore when they go out and stick to some of these very low carb ketogenic diets, or at least a large chunk of folks.

因此，这类饮食具有治疗用途，更不用说在严格控制的条件下，生酮饮食还能帮助治疗对药物干预无反应的儿童癫痫患者。

So there are therapeutic uses for these kinds of diets, not to mention the fact that under really controlled conditions, ketogenic diets can help treat children with epilepsy that have been resistant to pharmaceutical interventions.

我们还进行了另一项研究，采用了另一种生酮饮食，其中包含大量非淀粉类蔬菜，以尽可能使其更健康，并与一种不含任何动物产品、碳水化合物和淀粉含量较高的纯素饮食进行比较。

We did another study where we did another ketogenic diet, which had a lot of non starchy vegetables with it to try to make it as healthy as possible as compared to a vegan diet that didn't have any animal products and was higher in carbs and starches.

我们与研究免疫系统功能的专家合作，发现——当然，这还处于早期阶段，我们并不清楚这究竟意味着什么——但似乎当人们采用生酮饮食时，他们的适应性免疫系统会被激活。

And we collaborated with folks looking at immune system function and seeing how it seems like, and again, this is early days and we don't really know what this means, but it seems like when people go on a ketogenic diet, their adaptive immune system is amped up.

而当人们采用高淀粉的纯素饮食时，他们的先天免疫系统则会被激活。

Whereas when people go on a vegan high starch diet, their innate immune system is amped up.

与他们开始研究前的基线水平相比，两种饮食在多种指标上都表现得更好。

And both were better than when they started at baseline by various different markers.

这意味着什么，我认为我们还不清楚，但看到人们的饮食类型对如此多的生理功能产生影响，确实非常有趣。

What that means, I don't think we know, but it's really interesting to see how there's so many different physiological functions that are dependent on the kind of diet that people are on.

这对整体健康意味着什么？

And what does that mean for general health?

我们目前还不知道。

We don't know yet.

我们需要进行更多的研究。

We need to do more studies.

这对患有不同病理生理状况的人意味着什么？

What does it mean for people with different kinds of pathophysiologies?

这一点我们目前也不知道。

We don't know that yet either.

还有太多需要学习的东西，这令人兴奋。

There's so much more to learn, which is exciting.

是的。

Yeah.

我可能会请你稍微推测一下，这纯粹是我的医学好奇心。

I'm probably gonna be asking you to theorize a bit here, and this is just my medical curiosity.

生酮饮食与可能帮助癫痫儿童之间的联系，基于你在EP领域的研究，你是否看到它与心律失常之间可能存在某种关联？

The connection that exists between the ketogenic diet and potentially helping children with seizures, Given your research in the EP world, is there some sort of link with arrhythmias and ketogenic diet that you see a potential for?

我对这个一无所知

I don't know anything about

明白了。

that.

好的，

Okay,

懂了。

got it.

是的，这正是我之所以

Yeah, that's why I

只是

was just

因为酮症饮食在这些儿童身上起作用的机制是什么？也许你并不熟悉这一点。

because what is the mechanism by which, maybe again, you're not familiar with, but for why the ketogenic diet works in those children?

是的，实际上有各种各样的理论。

Yeah, mean, there's all sorts of theories.

这些理论涵盖了科学界最热门的术语，比如改变肠道微生物组，然后通过迷走神经影响大脑和神经兴奋性。

And they range everything from the hottest buzzwords in science of just altering the gut microbiome and that somehow through the vagus nerve gonna influence the brain and the sort of excitatory potential.

关于这一点，有各种各样的理论。

So there's all sorts of theories about that.

还有理论认为，当大脑使用酮体而非葡萄糖供能，或者酮体比例升高时，会改变细胞的氧化还原状态，从而影响其兴奋性。

There's theories about, well, when the brain is running on ketones as opposed to glucose or at least an increased proportion of ketones, that changes the redox state of the cell and that can change how excitable it is.

如果大脑更易兴奋，就更有可能引发癫痫发作。

And if it's more excitable, then you're more likely to kick off a seizure.

这些机制听起来都非常合理，也很有科学依据，甚至相当可信。

Perfectly reasonable sounding mechanisms, but that's one of the things that's interesting in this space is that many folks will have a very convincing mechanism that sounds very science y and maybe even quite plausible.

但当你试图设计一项研究来验证它时——无论是在动物、类器官还是人体中——就会发现事情没那么简单。

And yet then you should go and try to design a study to test it, whether it's in animals or organoids or humans.

对于

For

当然。

sure.

而且我们接下来要探讨为什么现在这会成为一个问题。

And we're gonna go into why that's problematic these days.

对，太好了。

Right, cool.

当然。

Sure.

所以，在你完成了这项研究的下一个关键步骤——采用极低碳水化合物饮食之后，你接下来做了什么？

So after you did the next building block of this research of doing the very low carb diet, where did you go

从那里继续？

on from there?

是的，直到那时，我们还做了另一个疯狂的《最重量级减肥者》研究，这也是另一个

Yeah, so up until that point, we did this crazy Biggest Loser study too, which is another Yeah,

是的，实际上我们来谈谈这个，因为这个经常被引用，而且可能以你并不希望的方式被引用。

yeah, actually let's talk about that because this gets referenced so much in probably ways that you wish it was.

是的，确实如此。

Yeah, it's true.

我的意思是，直到那时，我一直关注的是：当我们控制人们的饮食时，我们关注的是身体如何利用这些能量来源，以及新陈代谢是变慢还是变快，变化的效应量有多大？

Well, I mean, up until that point, I'd been focusing on, look, when we control people's diets, we are focusing on how the body is using those fuels and how is metabolism slowing up or speeding down, slowing down or speeding up, what are the effect sizes that we're seeing?

并且有一个案例中，我们确实开始看到非常显著的效果。

And there was one case where we actually started to see really big effects.

那就是《最重量级减肥者》这个研究，而且再次说明，这个研究是我当时在看真人秀时注意到的——看到这些人在一个节目结束时站上体重秤，我说：‘你减了15磅？’

And that was this Biggest Loser study, which was, and again, this was a study that I just was watching reality TV and saw these folks stepping on scales at the end of one episode, and I'm like, You lost 15 pounds.

我心想：‘这到底是怎么回事？’

Said, What the

我当时一直在研究，其中一项为我们的模型奠定基础的研究是明尼苏达饥饿实验，这是二战期间一些拒服兵役者自愿参与的实验，由安塞尔·凯斯主持。

hell is going on?

我参与构建了我们所建立的模型之一的基础性研究，那就是明尼苏达饥饿实验，该实验由安塞尔·凯斯在二战期间对拒服兵役者开展。

I'd been studying, built one of the kind of foundational studies for one of the models that we built was the Minnesota Starvation Experiment, which was done on conscientious objectors in World War II, who volunteered to serve their country by engaging in this starvation experiment that Ansel Keys conducted.

他们在相对较短的时间内减掉了大量体重。

And they're losing a lot of weight over a relatively short period of time.

我见过接受减重手术的人体重下降得很快，但也没快到每周减15磅的程度。

And I'd seen people with bariatric surgery losing weight at a pretty rapid pace, but not at 15 pounds a week.

这到底是怎么回事？

It was like, what is going on?

于是我看了更多这档节目的集数，看到很多教练在跑步机上对人大喊大叫，有人呕吐，而且根本没看到他们吃多少东西。

So I watched more episodes of this show and saw a lot of trainers yelling at people on treadmills and people throwing up and didn't really see them eating much.

但很明显，信息传达的是：运动才是减重的原因。

But the message was clear, it's like the exercise was responsible for the weight loss.

但他们的新陈代谢究竟发生了什么，却并不清楚。

But it wasn't clear what was going on in terms of their metabolism.

因为当时有一种观点认为，如果你做了足够的运动，我们从明尼苏达饥饿实验中知道，当人们通过节食减少热量摄入来减重时，他们的基础能量消耗——也就是身体在静止状态下维持生命所消耗的卡路里——会急剧下降。

Because there was this idea at the time that if you just did enough exercise, we know from that Minnesota starvation experiment that people when they lose weight by starvation cutting calories, their resting energy expenditure, the number of calories your body's burning just to kind of stay alive at rest before you're moving around crashes.

当减重过程中出现这种情况时，人们普遍认为这是非常糟糕的。

And it's viewed as a very bad thing when it comes to weight loss.

当然，对这些人来说，这可能避免了他们在饥饿实验中死亡。

Of course, for these folks, it probably prevented them from dying in the starvation experiment.

对。

Right.

但你说‘崩溃’时，具体是指下降到什么水平？

But And when you say crashes, what is the number drop in the basement

在明尼苏达饥饿实验的受试者中，基础代谢率绝对下降了百分之四十。

So rate in so in the Minnesota starvation subjects, it went down by an absolute amount of forty percent.

我想这说的是相对降幅。

I guess that's a relative amount.

减少了百分之四十。

Forty percent reduction.

其中一部分是可以预期的，因为如果你的细胞更少、身体质量更轻，活动所需的能量自然也会减少。

Now some of that's to be expected just because if you have less cells or less amount of mass of the body, you'd need less energy to move around.

但即使考虑到这一点，能量消耗的下降幅度仍高于预期。

But even when you account for that, there's a greater than expected reduction of energy expenditure.

这个有以卡路里为单位量化过吗？

Was that ever quantified with calories?

是的。

Yeah.

我在想明尼苏达饥饿实验中，我认为每天比预期多消耗了大约200卡路里。

So I'm trying to think of for the Minnesota starvation experiment, I think it was roughly 200 calories a day, greater than you would expect.

所以从绝对值上看，消耗量下降得更多，但由于他们失去了大量去脂体重，卡路里消耗的预期下降幅度也很大。

So it went down by more than that in an absolute sense, but because they'd lost so much fat free mass, there was a large expected reduction of calorie expenditure.

但即使如此，在饥饿期结束时，消耗量仍比预期低了大约200卡路里，而这些人已经变得非常缺乏活动。

But even then at the end of the starvation period, it was down by, I think it was a roughly 200 calories a And these folks had become very sedentary.

他们简直动不了，以前的运动员对自己感到沮丧。

It's like they couldn't move, like former athletes were frustrated with themselves.

他们在跑步机测试中都失败了，完全没力气。

They were failing their exercise treadmill tests, they just had no energy.

他们大部分时间都待着，幸运的是，明尼苏达那时是夏天。

They spent most of the time Fortunately, that was summer in Minnesota.

他们大部分时间都躺在阳光下，因为他们总是觉得冷。

They spent laying out in the sun because they were cold most of the time.

所以，正如你所预期的，这些饥饿的人变得脾气古怪，不愿意做任何家务之类的事情。

So they just became, as you might expect, starving people to be ornery folks who didn't want to talk about doing any of their chores and things like that.

而在这里，这些参加真人秀节目的人却以快得多的速度减重，并且进行了大量锻炼。

And so here were these folks on this reality TV program losing weight at a much faster clip, doing all this exercise.

我不知道他们到底吃了多少东西。

And I don't know how much they're eating at all.

当时有一种观点认为，只要你进行足够的锻炼，就能防止新陈代谢减缓，因为你能保持肌肉质量。

And there was this idea at the time that if you just did enough exercise, you could prevent the slowing of metabolism because you'd preserve your muscle mass.

很明显，这些人不仅在做有氧运动，还在进行力量训练、交叉训练等各种锻炼。

And it was clear these folks weren't just doing aerobic exercise, they were doing resistance training, cross training, all sorts of things.

于是又出现了另一个问题：他们到底吃了多少？

And then there was the other question, well, how much are they eating?

我们所看到的体重减轻，有多少是因为电视上展现的那些艰苦锻炼和挑战造成的，又有多少是因为他们真的在吃东西？

And what fraction of the weight loss that we're seeing is because of what's being portrayed in television, which is all this grueling workout and these challenges versus are they eating anything?

我完全不知道。

I have no idea.

所以我不记得我是怎么得到这个信息的，但我找到了负责这些人身体护理的医生的电话号码。

And so I don't remember how I got this information, but I found the telephone number for the doctor who is in charge of the care of the physique.

他在比弗利山庄有一家不错的小诊所。

He has this nice little Beverly Hills clinic.

我给他打了电话，这是我人生中第一次，我拿出名片说：您好，我是医生。

And I got him on the phone and I actually, for the first time in my life, I pulled out, Hi, this is Doctor.

霍尔

Hall

来自美国国立卫生研究院。

from the National Institutes of Health.

我想和您聊聊《最重量级减肥者》这个项目。

I'd like to talk to you about the Biggest Loser program.

我当时就说，

I was like,

是的，没错。

Oh yeah, yeah.

他是个非常外向的人，一个非常有趣的角色。

And he's a very gregarious guy, a really interesting character.

他叫医生。

His name's Doctor.

希泽加医生。

Hizenga, Doctor.

H在电视上。

H on TV.

他跟我讲了这个节目部分是他提出的主意，因为他曾经是当时洛杉矶突袭者队的队医。

And he told me about how it was partly his idea for this program because he used to be the team physician for, at that time, the LA Raiders.

他注意到许多线卫在一天两练时很难保持体重。

And he noticed that many of the linemen couldn't keep their weight up when they did two a day trainings.

这成了一个大问题，因为他们必须保持庞大的体型才能正确地比赛。

And that was a big problem because they had to stay massive to play the game correctly.

他想到的是，如果我们能让肥胖人群像职业足球运动员那样每天训练两次，会怎么样？

And he had the idea of, well, what if we could get people with obesity to exercise as much as a professional football player doing two a days?

这意味着他们别无选择，只能减重。

Mean, they wouldn't have any choice but to lose weight.

我想这正是《最重的减肥者》这个节目的创意来源之一，如今人们可能已经不记得这个疯狂的节目曾经播出了很多很多季。

And so I guess that was part of the pitch for The Biggest Loser and it became the crazy Nowadays, don't realize how popular that crazy program It was on for many, many, many seasons.

但不管怎样，我更感兴趣的是，他们真的能防止新陈代谢减缓吗？

But anyway, so I was more interested in, is it true that they can prevent the slowing of metabolism?

运动量有多大？

How much is the exercise?

因为你很明显地知道，他们通过大量的运动和极低的热量摄入，肯定会减重，所以你假设……

Because it was obvious to you that they would lose weight with the massive amount of exercise, the fact that they're cutting huge amounts of calories, you assumed

当时讨论的重点是，由于他们进行了大量运动，所以不会出现新陈代谢减缓的情况。

And right at the what was being talked about was that they wouldn't have the slowing of metabolism because they were doing this exercise.

是的。

Yeah.

所以，从逻辑上讲，你觉得这合理吗？

So Which logically, did that make sense to you?

不太合理。

Not really.

这正是我想说的。

That's what I'm saying.

是的，不太合理，这一直是我对那些做出这种说法的人的反驳，因为当你观察静息代谢率和骨骼肌时，它的数值其实很低。

Yeah, not really, that would always be my pushback against the folks who made that claim because when you look at the resting metabolism skeletal muscle, it's really low.

每公斤只有15卡路里。

It's only 15 calories per kilogram.

一公斤肌肉，也就是2.2磅肌肉，要在热量赤字状态下长出2.2磅骨骼肌非常困难，而回报却微乎其微。

And a kilogram of muscle, 2.2 pounds of muscle, it's hard to grow 2.2 pounds of skeletal muscle, all for the benefit While in a deficit.

是的，在热量赤字状态下，对吧？

Yeah, while in a deficit, right?

只为每天多消耗15卡路里的巨大好处。

All for the whopping benefit of 15 calories a day.

我的意思是，你是在开玩笑吧？

I mean, are

你是在开玩笑吧？

you kidding me?

这简直荒谬，对吧？

This is like nonsense, right?

但也许运动中还有其他因素在起作用。

But maybe there was something else going on with exercise.

也许某种激素方面的原因。

Maybe there was some sort of- Hormonal thing.

激素因素，或者蛋白质重建过程中的低效会消耗能量。

Hormonal thing or inefficiency and the rebuilding of the proteins costs energy.

有很多理由可能解释为什么这会提高新陈代谢。

There's all sorts of reasons why that might increase metabolism.

所以，这根本不是显而易见的，它可能完全是错误的。

So it wasn't a no brainer that this could be complete fallacy.

所以你

So you

对此持开放态度。

were open to it.

是的，当然。

Yeah, of course.

我认为每个人在考虑参与任何研究时都应当如此。

That's how I think everybody should go into every sort of study they're contemplating.

于是我给他们打了电话。

And so I got them on the phone.

我当时说：好吧，我们了解他们每天消耗多少卡路里吗？

I'm like, Okay, well, do we know anything about how many calories they're burning?

他回答：嗯，他们每天锻炼大约三个小时。

He's like, Well, they exercise for like three hours a day.

天啊。

Jesus.

我们可以做一些推测，但没有直接的测量数据。

And we can make some guesses, but no, we don't have any direct measurements.

我当时说，那你们有没有测量他们在静息状态下的卡路里消耗？

I'm like, do measure how many calories they're burning at rest?

他说，不，我们在这方面没有任何数据。

He's like, yeah, no, we don't have anything on it.

好的。

Okay.

你知道他们减掉的体重中，有多少来自体脂，有多少来自肌肉吗？

Do you know how much of the weight that they're losing comes from body fat versus muscle?

他回答说，哦，实际上，是的。

And he said, oh, actually, yeah.

因为他在比佛利山庄的诊所配备了和我们在NIH相同的体成分评估设备。

Because his Beverly Hills clinic was decked out with all the same body composition assessment equipment we had at the NIH.

他们有一台专为体型较大人群设计的双能X射线吸收仪。

They had a DEXA scanner for very large people.

他们还有一个Bod Pod。

They had a Bod Pod.

他们还有生物阻抗设备。

They had bio impedance.

他们拥有一大堆先进的仪器。

They had all sorts of toys.

所以他拥有所有参赛者各季的数据。

And so he had data from all the seasons of all the contestants.

是的，这正是他的专长。

Yeah, that's his wheelhouse.

这正是他感兴趣的方向。

That's what he's interested in.

他说，是的，他们减掉的脂肪远远超过接受减重手术的人。

He's like, yeah, they lose by far more fat than people who are on bariatric surgery.

考虑到他们所进行的锻炼，这一点是可以理解的。

And that kind of makes sense given the exercise that they were doing.

他们吃多少？

And how much are they eating?

嗯，我们给他们制定了最低摄入量的指导。

It's like, Oh, well, we give them instructions to eat above a certain amount.

那么，他们到底吃多少？

Like, okay, how much are they eating?

嗯，我们也不清楚。

It's like, Well, we don't know.

他们不是有专人准备餐食吗？

Don't They don't get their meals prepared for them?

不，不，不。

It's like, No, no, no.

他们自己动手做饭。

They do it themselves.

他们在马里布的牧场里有个厨房，里面 stocked with I promoters of the

And they just have a kitchen at this ranch in Malibu and it's stocked with I promoters of the

想在

think at

那时候用的是Jennie O火鸡。

that time it was Jennie O Turkey.

冰箱里全是Jennie O火鸡。

It's like everything Jennie O Turkey in this refrigerator.

总之，我当时就想，我很希望让我的一位博士后过来，在比赛期间对一些参赛者做一些测量。

Anyway, so I was like, Well, I'd be really interested in having one of my postdocs come out and maybe make some measurements on some of the contestants over the course of one of the competitions.

他对此非常感兴趣，说：好，我去跟制片人谈谈。

And he was really into it and he was like, Yeah, let me talk to the producers.

最后我们确实这么做了。

And eventually that's what we ended up doing.

我与我的同事、彭宁顿生物医学研究中心的埃里克·拉维森合作。

I worked with a colleague of mine, Eric Ravison at the Pennington Biomedical Research Center.

这是另一个很长的故事，NIH不让我做这项研究。

Another long story, the NIH wouldn't let me do the study.

他们说：‘不，我们不会与真人秀节目产生任何关联。’

They said, No, we're not gonna associate ourselves with reality TV.

那真是个错失的机会。

Missed opportunity there.

是的，我当时想，我可不是那种别人一说不就放弃的人

Yeah, and I sort of thought, I'm not one to take no for

至少不会因为第一次被拒绝就放弃。

an answer, at least not the first answer.

于是我在一次会议上遇到了埃里克，我对他说：‘埃里克，你看过这个节目吗？’

And so I met Eric at a conference and I said, Eric, have you ever seen this show?

他回答：‘是的，那是个糟糕的节目。’

He's like, Yeah, it's a horrible show.

当我担任肥胖学会主席时，我们曾给NBC写过一封严厉的信，批评这个节目具有污名化倾向。

When I was president of the Obesity Society, we wrote a scathing letter to NBC about how stigmatizing it is.

我说：‘是的，是的，我同意。’

I'm like, Yeah, yeah, I agree.

你不想研究他们吗？

Wouldn't you like to study them?

他告诉我，他让他的博士后感兴趣了，最终我们把为NIH撰写的方案修改后提交给他们的机构审查委员会，并获得了批准。

And he's like, I got his postdoc interested, and eventually we took the protocol I'd written for NIH and modified it for their IRB and it got approved there.

于是我们派出了博士后和一些设备前往马里布进行测试。

And so we sent out our postdocs and some equipment to Malibu to test.

事实上，在参赛者还不知道自己是参赛者之前，我们就已经寄送了物资给他们。

In fact, we sent supplies to the contestants before they knew they were contestants.

在家时，我们拿到了被选中者的名单，给他们提供了体重秤和双标水，用来测量他们在知道自己上节目之前每天消耗的总热量。

At home, we got the list of the folks who were selected, and we gave them scales, we gave them doubly labeled water, to measure how many total calories they were burning even before they knew they were on the show.

当他们前往马里布后，我们 setup 了一个小型的伪代谢实验室，用代谢车测量他们的静息代谢率。

And then when they went to Malibu, we set up a little pseudo metabolic unit where we had people measuring their resting metabolic rate with metabolic carts.

我们设计这项研究只是为了评估：他们的代谢率是否随着体重下降而按预期变化，还是存在其他额外因素？

We designed the study to just assess, did their metabolic rate change by the amount that you'd expect given their weight loss, or was there something extra going on?

还是说，他们能够将代谢率维持在较高水平——正如许多运动与生理学领域的专家所预测的那样。

Or were they able to preserve their metabolic rate at a higher level as many of the folks in the exercise and physiology community had predicted.

所以我们多次回到了那里。

And so, so we went back out there several times.

我说的‘我们’，其实主要是那些博士后，别让我碰设备。

I say we, mostly the postdocs again, don't let me touch equipment.

当减肥计划结束时，我们拿到了数据，结果非常有趣，因为他们的平均热量摄入减少了约65%。

And when we got the numbers back at the end of the weight loss program, it was really interesting because they had on average, they cut by about 65% of their calories.

热量摄入大幅削减。

Huge cut in calories.

立刻就开始了。

Right away.

是的，在比赛期间，他们大幅减少了热量摄入。

Yeah, like during the competition, they just cut calories enormously.

他们每天进行的运动量相当于三小时的剧烈运动。

And they were doing the equivalent of three hours of vigorous exercise a day.

他们的每日热量消耗增加了约一千卡路里。

And their calorie expenditure went up by about a thousand calories per day.

所以他们处于巨大的热量赤字中，每天减重一磅。

And so they're eating this huge deficit and they're losing weight at a rate of a pound a day.

还有另一件事。

That's the other thing.

电视上的内容不是现实，所以

TV time is not reality So

所以当他们在

So when they lose 15 pounds in

一周内减掉15磅，实际上是在剧集之间的十二到十五天内减掉的。

one It's show more like 15 pounds over twelve to fifteen days between episodes.

所以这并不是真实的一周。

So it's not a real week.

我早就学到了一件事。

I saw it was one thing I learned really early on.

但在牧场期间，他们的平均减重速度是每天一磅。

But the average weight loss was a pound a day when they were on the ranch.

这个节目的运作方式是，人们会时不时被投票淘汰。

The way the show worked is that people got voted off occasionally.

十三周结束后，所有人都回家了。

Then at the end of thirteen weeks, everybody went home.

他们在第三十周时回来参加重聚活动，或者说是电视节目的总决赛，以决出最大的输家。

They came back at week thirty for this reunion or I guess the finale of the TV show to whoever be crowned the biggest loser.

即使在他们回家后，他们仍然以每天大约半磅的速度减重。

And at that point, even when they went home, they're still losing weight at about a half pound a day.

所以他们的减重速度减半了，但依然保持着巨大的热量赤字，并且每周每天都进行大约一小时的剧烈运动。

So cutting their rate of weight loss in half, but still a huge deficit and still doing about an hour of vigorous exercise every day of the week.

因此，说肥胖者没有意志力完全是无稽之谈。

So the idea that people with obesity don't have willpower is just nonsense.

这需要惊人的意志力。

This is an insane amount of willpower.

当他们在马里布时，他们离开了家人；回来后，他们试图回归平常的生活，但即便如此，他们仍然能够持续数周甚至数月坚持这样做。

And then they left their families while they were in Malibu, they came back and they tried to go back to their usual life, and yet they're still able to do this for weeks and weeks and weeks at a time.

当我们观察代谢率时，它急剧下降了。

And then when we looked at the metabolic rate, it crashed.

它下降的程度明显超过了根据他们身体成分变化所预期的幅度。

It had clearly gone down more than you would expect based on their body composition changes.

我们说的是，平均每天比预期多减少了400卡路里。

And we're talking on average 400 calories a day more than you would expect.

然后我们感兴趣的是，这种代谢减缓是否能预测谁后来会反弹体重？

And then what we were interested in was did that slowing of metabolism predict who would regain weight later?

因为当时还流传着另一个误解。

Because that was another myth that was out there.

那时这还不是误解，我们尚不清楚：代谢率下降最多、消耗卡路里最少的人，应该是最容易反弹体重的。

It wasn't a myth at the time, we didn't know, was that the people who would have burnt the fewest number of calories because their metabolism had slowed down the most, they should be the ones who are most susceptible to weight regain.

到这个时候，美国国立卫生研究院（NIH）已经加入进来。

And so we brought, by this point, the NIH had come on board.

因此在六年时点，我们把所有人（除了两人）都召回了NIH临床中心，进行后续测量。

And so at the six year mark, we brought everybody back, actually minus two people, to the NIH Clinical Center to have the follow-up measurements.

平均而言，他们重新增回了大约三分之二的减掉的体重。

And on average, they regained about two thirds of the lost weight.

我们有一个人甚至继续减掉了更多体重。

We had one person continue to lose even more weight.

有些人不仅把所有减掉的体重都增了回来，还超过了原来体重。

Some people regain all of the weight and more.

因此，体重反弹和持续减重的范围非常广泛。

So it was a wide range of weight regain and continued weight loss.

但在体重减轻结束时，他们的新陈代谢减缓了多少卡路里与谁重新增重之间没有任何关联。

But there was no relationship between how many calories their metabolism had slowed at the end of the weight loss period and who had regained.

我们无法预测这一点。

We couldn't predict it.

最令人震惊且引起媒体广泛关注的是，尽管他们重新增重了，但正如我们之前提到的，体型较大的人基础代谢率更高，静息时消耗更多热量，而他们的平均代谢率却并未从减肥比赛结束时的水平回升。

And the most shocking thing and the thing that got all the press attention was the fact that despite regaining the weight, like we we've mentioned before, larger bodies have higher metabolisms, burning more calories at rest, they're on average didn't change from at the end of the weight loss competition.

所以他们的代谢率永久性降低了。

So they permanently decreased.

是降低了，是的。

It was decreased, yeah.

它仍然处于这个低水平。

It was still at this low level.

即使他们仍然轻了三分之一？

Even though they were a third still lighter?

因为他们重新增重了三分之一、三分之二，但他们

Because they regained a third, two thirds, but they

有

had a

三分之一比他们当初

third lighter than when they

是的，是的，平均而言，他们仍然比原来轻了三分之一，我原本以为随着体重恢复，他们的基础代谢率会上升。

Yeah, yeah, so they were still down by a third on average, and my expectation was that their resting metabolic rate would go up as they regained weight.

但他们并没有。

And they didn't.

而这种情况并没有发生。

And that didn't happen.

这让我感到非常震惊。

And that was so shocking to me.

我当时想，好吧，我们当时测量和现在测量之间有什么不同？我们意识到当时用的是不同的设备来测量新陈代谢。

I was like, all right, what's different between when we measured it then and when we measured it now and we realized we were using different actual pieces of equipment to measure metabolism.

我们在马里布时用的是彭宁顿中心的设备，而在这里用的是NIH的设备。

We used the one from the Pennington Center when we were out in Malibu using the NIH one.

好吧，我们在两次测量时都进行了校准，但这是有可能的。

Like, okay, well, we calibrate them on both occasions, but it's possible.

我们把彭宁顿中心的设备运到NIH，看看它们的测量结果是否一致，但结果并不是这个原因。

Let's fly the one at the Pennington Center to the NIH to check and see if they're measuring the same, and that wasn't it.

它们测量的结果是一致的。

They were measuring the same thing.

所以我们别无选择，只能相信这些数据，不管它多么难以置信。

So we had no choice but to kind of, you gotta believe the data as unbelievable as it is.

然后情况变得更奇怪了，因为当我们查看谁最成功地保持了体重时，发现那些新陈代谢减缓最明显的人反而最成功。

And then it got even stranger because when we looked to see who was most successful at keeping the weight off, it was the ones who continued to have the greatest slowing of metabolism.

这简直是矛盾接二连三地出现

It's like contradiction after

矛盾，而在此之前，我们发现马里布的情况也是如此。

contradiction And before you would it turned out that that was also true in Malibu.

减重最多的人，正是那些新陈代谢减缓最厉害的人。

The ones who had lost the most weight were the ones who had slowed their metabolism the most.

另一个有趣的发现是，当我们分析谁运动最多、体力活动最频繁，以及谁最严格控制热量摄入时，发现体力活动的差异与减重效果之间没有任何相关性，但那些最严格控制饮食热量的人减重最多。

Another piece that was kind of interesting was that when you look for a correlation between who was doing the most exercise or the most physical activity versus who was cutting their calories and their diet the most, It was there was no correlation between the differences in physical activity and weight loss, but whoever cut their calories the most lost the most weight.

他们正是那些新陈代谢减缓最显著的人，而在六年之后情况完全逆转了。

They were the ones who kept their had the greatest slowing of metabolism and the complete flip at six years.

那些增加体力活动最多的人，新陈代谢反而最慢，而且在减重方面也最成功。

The ones who had ones who had increased their physical activity the most had the slowest metabolisms and had the most success at weight loss.

很有趣。

Interesting.

而能量摄入——卡路里摄入——那里也没有相关性。

Whereas energy intake didn't calorie intake didn't there was no correlation there.

所以真是奇怪的事情。

So really weird stuff.

结果发现，其中一些现象在其他群体中得到了重复验证，但并非全部。

Turns out that some of those things have been replicated in other cohorts, but not all of them.

那里仍然有一些谜团。

And there's still some mysteries there.

但我们喜欢这样理解，或者至少我现在喜欢这样想：要解释能量消耗、新陈代谢减缓与体重变化之间的关系，唯一的方式是将其视为一种反应，而不是决定因素。

But the way we like to think about it, or at least the way I like to think about it now, is the only way to make sense of that relationship between energy expenditure and metabolic slowing and weight change is that it's a response, not a determinant.

换句话说，把新陈代谢减缓想象成弹簧的张力，你有一根弹簧，什么也不做时，就没有张力。

In other words, that think metabolic slowing like the tension on a spring, and you've got the spring, you're not doing anything, and there's no tension.

你拉伸弹簧，这相当于减重，你能拉多远，张力就越大，回弹力也越强。

You pull the spring, that could be the equivalent of weight loss, however much you can pull the spring, you get a greater tension and there's greater pullback.

这就是新陈代谢的适应性。

And so that's the metabolic adaptation.

你拉得越多，减重就越多，反弹也越强。

You pull more, you get more weight loss, and you get more pullback.

但这种反应始终与拉力成比例，是对拉动力量的成比例回应。

But it's always in proportion to the It's a proportionate response to the amount that you're pulling.

因此，无论出于什么原因，那些在《最重量级减肥者》比赛或六年后的生活中最成功地做出生活方式改变的人，虽然减重最多，但也经历了最大的代谢反弹压力。

So for whatever reason, the people who are most successful at making those lifestyle changes either on the ranch in the Biggest Loser competition or in their lives six years later will get the most weight loss, but they'll also experience the greatest tension on the spring, the greatest amount of pullback of metabolism.

令人沮丧的是，当我们公布这一发现并引发大量媒体报道，甚至登上《纽约时报》头版时，却没有一家媒体准确报道。

And the frustrating thing was that when we reported that and it got all this press attention, was literally on the front page of the New York Times, no one reported it right.

他们是怎么报道的？

How are they reporting?

他们说，是代谢减缓导致他们重新增重。

They were saying, Oh, it's the slowing of metabolism that caused them to regain the weight.

但这并不是实际情况。

Which is not the pattern.

这根本不是规律。

It's not the pattern.

我们发现这两者之间没有相关性，这正是他们无法保持减重的原因。

We saw no correlation between those two things, and that this is the reason why they can't keep the weight off.

他们说，不，那些减重最多的人，反而减得更多，他们的新陈代谢减缓得最厉害。

They're like, No, the people who kept the most weight off, lost even more weight, they had the greatest slowing of metabolism.

因此，这并不是决定性的因素。

And so it's not determinative.

这未必有帮助。

It's not helpful necessarily.

换句话说，

In other words,

所以，弹簧的类比也是成立的，因为本质上弹簧最终会失去弹性。

So does it it also, the spring analogy works because essentially the spring ends up losing its elasticity.

是的。

Yeah.

如果你能神奇地以相同的拉力持续拉伸弹簧，然后突然神奇地解除拉力，弹簧当然会被拉到无限长。

If if you magically you're pulling at it with the same tension, you magically cut the tension on the spring, of course, you'd pull it to infinity.

对吧？

Right?

但这样一来，你会更加成功。

But so you would be even more successful.

对吧？

Right?

也就是说，终有一天它不会再弹回。

But meaning that at some point it doesn't bounce back.

某个时刻，它不会恢复原状。

Some point, well It doesn't recoil.

嗯，不，到了某个时候这反而会变得容易。

Well, no, at some point that would make it easy.

那么你会认为，最成功的人，如果你等得足够久，弹簧的张力应该是最小的。

Then you would suggest that the people who are most successful, if you waited long enough, we should have the least tension in the spring.

但事实并非如此。

That's not the case.

我不认为它是以这种方式重置的。

I don't think it resets that way.

至少我们在六年内没有看到任何重置的证据。

At least we didn't see any evidence of resetting over six years.

但为什么当

But how come when

他们重新长胖后，你认为为什么代谢率没有回升呢？

they gained the weight back, what is your theory as to why the rate didn't go back up?

这正是我想说的

That's what I

我的意思是

mean, that

弹簧卡住了。

the spring gets stuck.

所以，再次强调，这完全是推测，但当你观察生态学中的一个概念时，我们会为身体所做的每一件事分配能量预算，对吧？

So again, complete speculation, but when you look at There's this idea from ecology where we have energy budgets for different amounts of Everything that we do in our bodies cost energy, right?

这一观点最近由赫尔曼·庞泽尔推广开来，他撰写了《燃烧》一书，对该理念进行了精彩的阐述。

And this was most recently popularized by Herman Ponzer, who wrote the book Burn, which is a great exposition on this idea.

因为他研究了那些身体非常活跃的狩猎采集部落，而他们的体型也更小，因此必须根据体型进行调整。

Because he looked at hunter gatherer tribes who are very physically active and they're also smaller, so you have to adjust somehow by their body size.

但当你根据体型调整后，观察他们每天消耗的总热量时，发现与久坐的办公室职员并无差异。

But when you adjust their body size and you look at how many calories they're burning in total, it's no different than sedentary office workers.

因此，在广泛的体力活动范围内，似乎存在某种权衡机制。

And so for a wide range of physical activities, it seems like there's some sort of trade off going on.

我们在《最重的减肥者》中看到的是，那些变得最活跃的人——顺便说一句，他们所有人都比基线时活跃得多——可能由于诸多合理原因，他们的代谢率下降了。

And so what we saw in The Biggest Losers was that the ones who'd become the most physically active, and by the way, they'd all become much more physically active than they were at baseline, that perhaps for many good reasons, their metabolic rate dropped.

例如，如果他们的肝脏产生的促炎蛋白减少了，而蛋白质合成是一个耗能的过程。

So for example, if their liver is making less pro inflammatory proteins, Protein synthesis is an energy consuming process.

也许正是因为他们的体力活动增加了，身体才降低了这些过程的活跃度。

Maybe that is getting toned down because they're now more physically active.

我们知道，体力活动对这类生理过程确实有积极影响。

We know physical activity does have a beneficial effect on these kinds of processes.

其他例子包括那些参加或训练马拉松的女性运动员。

Other cases are the example of female athletes who do or are training for marathons and things.

她们会停止月经。

They stop menstruating.

而这背后是有能量代价的。

And so there's an energy cost to doing that.

也许这种能量分配方式会随着体力活动量的变化而改变。

Maybe this kind of budgeting of energy is changing depending on the amount of physical activity.

所以我认为，平均而言，我们的推测——这仅仅是个推测——是人们在参加《最重量级减肥者》比赛时，并不是特别活跃。

So I think that on average, our sort of guess, and it's only a guess, is that people when they started the Biggest Loser competition, they were not particularly active.

他们在比赛期间变得异常活跃，但这种程度是无法持续的。

They become crazy active during the competition, unsustainably so.

但许多人还是能够将这种活动融入日常生活。

But many of them kind of are able to incorporate that into their daily life.

尽管他们重新增回了三分之二减掉的体重，但平均而言，他们仍比开始时轻了12%；六年过去了，最成功的人仍然是那些进行最多体力活动的人。

And even though they regained two thirds of the lost weight, by the way, they're still down, I think 12% on average from where they started six And years the ones who are most successful are doing the most physical activity.

而他们正是新陈代谢减缓最明显的人。

And they're the ones who have the greatest slowing of metabolism.

因此，也许你的身体分配给体力活动的能量与这些其他代偿性代谢变化之间存在某种相互作用。

So maybe there's this interplay between the energy that your body's devoting to physical activity and these other compensatory metabolic changes that are going on.

纯粹是猜测。

Complete speculation.

是猜测，但这能强化一个观点：为什么仅靠运动减肥如此困难。

Speculation, but it would strengthen the notion of why it's so difficult to lose weight with just exercise.

是的，是的，是的，完全正确。

Yeah, yeah, yeah, absolutely.

我的意思是，确实有这一方面，这也是赫尔曼·蓬泽一直强调的观点。

I mean, there is that aspect, and that's been one of the messages that Herman Ponzer has been talking about.

最近有一篇论文基于一大群人使用双标水和静息能量消耗的数据探讨了这个问题。

And there was a recent paper about this in a big cohort of folks using doubly labeled water and resting energy expenditure.

但它真正揭示的是，代谢可能会产生巨大的影响，但这些影响恰恰与许多人预期的关于体重减轻和维持减重成果的方式完全相反。

But it really spoke to the idea that you could have these big effects on metabolism finally, but they worked in exactly the opposite way that many people thought they would work in terms of how they relate to weight loss and success at maintaining weight loss.

所以你做了这项研究，发现了所有这些非常有趣、或许出人意料的发现。

So you do this research, you find all of these very interesting, perhaps unexpected findings.

《纽约时报》刊登了错误的内容，但他们部分说对了。

The New York Times is publishing the incorrect They got some of it right.

嗯，他们部分说对了。

Well, They got some

部分说对了。

of it right.

但主要的结论，他们搞反了，走向了错误的方向。

But the major takeaway, they kind of flipped and went in the wrong direction.

那该怎么办？

What do do?

不只是他们的问题。

Wasn't just them.

我的意思是，这不仅仅是

I mean, it was

就像，我

like, I

我的书的合著者也承认，哦，是的。

mean, even my coauthor of the book, she admits, oh, yeah.

我也把那个报道错了。

I I reported that wrong too.

所以

So what

当你看到这些标题不断出现时，你会怎么做？你心想：等等，等等，那并不是

what do you do in that moment when you're seeing these headlines pop up and you're like, Well, wait, wait, that's not the

是的，关键是，另一个很明显的问题是，人们显然把新陈代谢和体重联系在一起，但这种联系并不准确，而且严重分散了人们对新陈代谢真正精彩科学的关注。

Yeah, well the thing is that the other thing that was obvious was that people were clearly tying the concept of metabolism to weight in a way that wasn't accurate and was also very distracting from the really wonderful science of metabolism.

新陈代谢存在于所有生物体中，甚至当人们寻找火星上生命迹象时，也会寻找新陈代谢的迹象。

Metabolism is in common among every living organism, And even folks when they look for signs of life on Mars, they look for signs of metabolism.

正因为新陈代谢如此基础，它才使得复杂生物体得以存在，因为正是这个过程让我们能够利用食物提供的能量和物质，或者在植物新陈代谢的情况下，利用阳光和空气。

And because it's so fundamental, it's the thing that allows complex organisms to be there because that process by which we're harnessing the energy and matter from the foods that were being provided or even the sun and the air in the case of plant metabolism.

这种物质和能量的流动，使得人类和所有其他生物得以存在。

And this flow of matter and energy is what allows humans and every other living thing to exist.

因此，看到大众对新陈代谢的概念不仅在预测方向上存在错误，还将其与体重视为唯一重要的因素，这让我感到沮丧。

And so it was frustrating to see the popular concept of metabolism not only being wrong in terms of directionality of its predictions, but its link with weight as the only thing that's important here.

完全忽视了我们身体的每一个细胞都在进行新陈代谢这一事实。

And just ignoring the fact that every cell of our body is doing metabolism.

这是一种复杂的生化之舞，具有不可思议的能力，能将我们摄入的食物和呼吸的空气转化为我们自身的一切以及我们所做的一切，正如我的朋友查理·布伦纳喜欢说的那样。

It's this complex biochemical waltz of miraculous ability to turn the food and air that we breathe into everything that we are and everything that we do, as my friend Charlie Brenner likes to say.

而忽视了这一过程的奇妙与震撼，我认为这实在令人着迷。

And just missing that, the wonder and awe of that process, which I think is just fascinating.

这正是我们这本书所探讨的一部分，即让人们认识到这种自然的奇迹，不应仅仅被简化为‘只是关于体重’。

And that's kind of part of what our book is about is to kind of give people that appreciation and the idea that we're thinking of this miracle of nature as, Oh, it's just about weight.

我很好奇，想更深入地了解你对运动可能是导致代谢率下降的关键因素这一推测。

I'm curious to better understand your speculation as to the exercise being the component that's driving the potential drop in metabolic rate.

假设‘最失败者’实验中完全没有运动成分，而仅仅是一个近乎绝食的实验，你是否仍会预期看到同样的结果，在

If, let's say, the biggest loser had no exercise component, if it was just strictly a mini starvation experiment, essentially, would you have expected to see the same Yeah, in the

我的意思是，已经有一些研究观察了那些减重后又部分反弹的人，他们没有进行运动，但新陈代谢率却上升了。

and I mean, there have been studies that have looked at people who have lost weight and regained some of that weight, and they did not have an exercise component, and metabolic rate goes up.

很有趣。

Interesting.

并不是

Not

所以这就不只是推测了。

So that's only not speculation then.

有没有一些研究支持这一点

Is it backed by some

嗯，那是另一组人，这些研究也有其局限性。

of Well, it's a different group of people, there are limitations to those studies as well.

正确的方法是进行随机分组。

The way you would do it is you do a randomization.

你会选取一组人，随机分配他们只进行饮食控制，或饮食加运动，然后长期跟踪，测量他们能量消耗的不同组成部分以及身体成分的变化。

You'd take a group of people and you randomize them to a diet alone or a diet and plus you'd follow them up for long periods of time and you would measure different components of energy expenditure, their body composition over time.

另一件非常有趣的事情是，尽管《最重量级减肥者》这项研究显得荒谬可笑，但真正对同一批人进行多年重大变化后反复测量的研究却极少。

And that was the other thing that was really interesting was that as silly and stupid as this Biggest Loser study was, there are a very small number of studies that have made those types of repeated measurements on the same people over time as they undergo major changes over years.

你有持续几周的减重研究，也许有一年的减重研究，然后你就放任他们不管了，也许只在其中一部分人中观察后续情况。

You've got your several week long weight loss studies, maybe a year long weight loss study, and then you've kind of let them go and maybe we'll see what happens in some subset of them.

但这种情况并不常见。

But that's not often the case.

而这些正是极为罕见的例子。

And those are the very rare examples.

也许这是因为资金周期通常只持续五年左右，但谁又知道呢？

And who knows, maybe that's because of the funding cycles and they only last typically five years or so.

目前还不清楚为什么会这样。

It's not exactly clear why that's the case.

但当我回头查看时，我震惊地发现：我们到底有多少研究可以用来与之对比？

But I was shocked when I went back and said, Okay, well how many studies do we have to compare this to?

即使是那种荒谬的、非随机的、偶然发生的自然实验。

Even the silly non randomized study, kind of an opportunistic experiment that was natural experiment, natural experiment that was happening.

实际上这样的研究并不多，但我们现有的这些研究都没有涉及大量运动，却观察到他们的新陈代谢率上升了。

There really aren't that many, but the ones that we do have didn't involve a lot of exercise and they did see their metabolic rate going up.

这再次为那种推测提供了一些支持，但我认为这真的只是推测。

So which again lends some support to that speculation, but I think it really is speculation.

显然，你可以做得更好，进行这项研究。

You could do that study better, obviously.

现在人们是如何误用或误用这项研究的成果的呢？

How are people these days misusing the research from that study or misapplying the research.

是的，我的意思是，还是同样的问题，他们认为新陈代谢在某种程度上决定了减重的成功与否。

Yeah, mean, I think it's still the same thing, which is that they think that metabolism is somehow determinative of weight loss success.

但在《最大减重者》这个案例中并非如此。

And it wasn't in the Biggest Loser case.

这实际上也反映了我研究方向的重大转变，即我原本专注于碳水化合物与脂肪对能量消耗的微小影响，或体脂变化，甚至在这种情况下，新陈代谢的巨大影响结果却与预期相反。

And it kind of actually speaks to what ended up being a huge shift in my research program, which was I'd been focusing on either really small effects of carbs versus fat and energy expenditure or body fat changes, or even in this case, big effect on metabolism that turned out to work in the opposite direction.

所以我开始思考，也许更多的关键作用发生在食欲和食物摄入这一侧。

So I started to think, okay, well maybe more of the action is happening on the appetite and food intake side of the equation.

我们一直进行这些研究，测量人们吃了什么，甚至控制他们吃的东西，但我们还没有做过让人们自由进食并试图理解食欲是如何被调控的研究。

We'd been doing these studies where we were measuring what people were eating or even controlling what they were eating, but we hadn't done studies where we tried to let people eat whatever they wanted and try to understand how is appetite controlled?

食欲与体重变化有何关联？

How does it relate to body weight change?

当人们减重时，他们的食欲是否会下降？

Is there some sort of feedback of as people lose weight, do they become their appetite go less?

是的，确实有一些轶事证据，人们报告了这种情况，甚至观察到与食欲相关的激素水平发生了变化，这些变化支持了这一观点。

Yeah, mean, there's anecdotes about this and people report this and have even seen changes in hormone levels that would tend to support this, these appetite related hormones.

但这些变化在数量上是如何相关的？

But how is that quantitatively related?

这种变化在长时间内是如何体现的？

How does that play out over long periods of time?

我们的食物和饮食环境有哪些特性，可能会改变食欲调控的基本生物学机制？

And what is it about our foods and our food environment that might actually change the basic biology of appetite control?

这就引出了一个问题：为什么我们会出现肥胖流行？

And that gets now to the question of why do we have an epidemic of obesity?

现在和以前有什么不同？

What's different now compared to before?

我们知道，肥胖的遗传性中有一大部分，在特定环境中，体型的40%到60%甚至70%是可遗传的。

We know that a huge chunk of the heritability of obesity, there's somewhere between forty and sixty or seventy percent of body size in a given environment is heritable.

我们现在已发现了超过一千个与体型相关的基因或单核苷酸多态性，尤其是与BMI相关。

And we've now come up with more than a thousand different genes or at least single nucleotide polymorphisms that are correlated with body size, BMI in particular.

其中绝大多数似乎是作用于中枢神经系统、很可能在大脑中的基因。

Most of those, the vast majority, seem to be genes that are acting in the central nervous system, in the brain likely.

这是如何运作的？

How does that work?

那里究竟发生了什么？

What is going on there?

这些遗传易感性与我们的环境之间有何相互作用？

And what is the interaction between those genetic susceptibility and our environment?

是与体力活动方面有关吗？

Is it on the physical activity side of things?

是食物环境方面的原因吗？

Is it on the food environment side of things?

是我们环境中某些完全不同的因素导致了这种变化吗？

Is it something completely different in our environments that may be causing this change?

还是说这是一种普遍的意志力缺失，在20世纪70年代和80年代中期同时出现在所有人身上？

Or is it a general lack of willpower that manifests simultaneously in all people around the mid 1970s and '80s.

顺便说一下，已经有人研究过这个问题。

By the way, there have been folks who have studied this.

他们查看了是否有其他指标能反映尽责性和意志力。

They've looked to see, well, are there other metrics that might be about conscientiousness and willpower?

比如人们系安全带这类行为，其发生率并没有变化。

Did people wear seatbelts and these kinds of behaviors that there's no difference in the rates.

显然，在安全带普及之前，这并不是一个好例子。

Obviously, when before seat belts were popular, it's not a good example.

我不太记得具体是哪些例子了，但没有证据表明，在肥胖率上升的这段时间里，人们的尽责性或意志力出现了显著变化。

I don't remember exactly what the examples were, but there was no evidence that there was these dramatic changes in conscientiousness or willpower over the course of the time that we had this increase in obesity prevalence.

而且它在所有年龄组和全球范围内同时发生。

And the fact that it happened simultaneously in all age groups and all Internationally.

但它在全球范围内并不是同时发生的，对吧？

But it's not simultaneous internationally, right?

因为麦当劳花了一段时间才普及。

Because it took a while to get McDonald's.

是的，我们

Yeah, we

在某种程度上在这方面领先世界。

were leading the world in that respect in some sense.

那么，到底是什么原因呢？

So what is it?

我们真的能仅凭食物供应的变化来解释这一点吗？

And can we actually even explain that based on just the changes in the food supply?

那将是其中一种情况。

That would be one thing.

还是我们可以根据体力活动的变化来解释它？

Or can we explain it based on changes in physical activity?

所以我对这类问题产生了兴趣。

So I got interested in those kinds of questions.

于是，我试图建立数学模型，来计算增重需要多少成本？

And then, so I was trying to building these mathematical models of how much does it cost to gain weight?

增重并沉积组织需要多少卡路里？

How many calories does it cost to gain weight and deposit tissue?

新陈代谢是如何变化的？

And how does metabolism change?

身体成分是如何变化的？

How does body composition change?

能量消耗是如何变化的？

And how does energy expenditure change?

这原本会是我过去研究的主要内容。

And that would've been much of my research previously.