Sleep Is Your Superpower | Matt Walker | TED

Summary

这个演讲强调了睡眠对健康的重要性。研究表明，睡眠不足会影响男性的生殖健康和女性的生育能力，降低记忆力和学习能力，增加患癌症和心血管疾病的风险，甚至改变基因活动。演讲者提供了改善睡眠质量的建议，如保持规律的睡眠时间和保持卧室凉爽，并强调睡眠不是奢侈的生活方式，而是生命的必需品。

Takeaways

• 😴 睡眠不足对男性生殖健康有显著影响，每晚睡五小时的男性睾丸体积比睡七小时以上的男性小。
• 💤 睡眠不足会导致男性体内睾酮水平下降至相当于比实际年龄大十岁的水平。
• 👩‍🔬 女性生殖健康同样会受到睡眠不足的负面影响。
• 🧠 睡眠对于学习和记忆至关重要，睡眠有助于巩固新记忆，缺乏睡眠会导致记忆力下降。
• 🧠 睡眠不仅在学习后重要，在学习和接收新信息前也需要睡眠来准备大脑，以便更好地吸收新知识。
• 🔬 实验表明，全夜不睡会导致新记忆形成的能力下降40%，这对教育群体的睡眠状况提出了警示。
• 🦷 睡眠对大脑的海马体有重要影响，海马体是大脑接收和保持新记忆文件的‘信息收件箱’，缺乏睡眠会关闭这个‘收件箱’。
• 💤 深度睡眠阶段的大脑波动和睡眠纺锤波有助于将短期记忆转移到长期记忆存储区域，保护记忆不受损失。
• 👴 随着年龄增长，睡眠质量尤其是深度睡眠质量会下降，这与认知能力和记忆的衰退有关。
• 🧠 睡眠中断可能是导致老年人认知衰退和阿尔茨海默病的一个被忽视的因素，改善睡眠质量可能有助于减缓这些症状。
• 🏥 通过非药物治疗如电流刺激大脑的方法，可能有助于增强深度睡眠的脑波，从而提高记忆力。
• 💪 睡眠不足会严重影响免疫系统，如自然杀伤细胞活性大幅下降，增加多种癌症的风险。

Q & A

为什么男性每晚只睡4到5小时会有较小的睾丸？

根据演讲内容，男性每晚只睡4到5小时会导致睾丸显著缩小，与每晚睡7小时或以上的男性相比。这是因为睡眠不足会影响男性的睾丸激素水平，进而影响生殖健康。

睡眠不足如何影响大脑的记忆和学习能力？

睡眠不足会严重影响大脑的记忆和学习能力。睡眠是学习后巩固新记忆的关键过程，相当于按下保存按钮，防止遗忘。此外，睡眠也有助于大脑在学习前做好准备，类似于干燥的海绵准备吸收水分。缺乏睡眠会导致大脑的记忆回路变得像水浸过一样，无法吸收新记忆。

海马体在大脑中扮演什么角色？

海马体在大脑中扮演着信息接收箱的角色，它非常擅长接收新的内存文件并保持它们。在睡眠充足的人中，海马体展现出丰富的与学习相关的健康活动。而在睡眠剥夺的人中，海马体几乎找不到任何显著的信号，就像睡眠剥夺关闭了记忆接收箱，任何新的传入文件都被弹回。

深度睡眠中的大脑波动和睡眠纺锤波有什么作用？

深度睡眠中的大脑波动和睡眠纺锤波共同作用，像夜间的文件传输机制一样，将记忆从短期易失性储备转移到大脑中的更长期稳定存储位置，从而保护这些记忆，使它们安全。

睡眠对老年人和痴呆症患者有何重要性？

随着年龄的增长，我们的学习和记忆能力开始衰退，这部分是因为深度睡眠的质量变差。研究发现，深度睡眠的破坏是导致认知衰退或记忆衰退的一个被忽视的因素。因此，改善睡眠质量，特别是深度睡眠，可能有助于恢复老年人和痴呆症患者的学习和记忆功能。

睡眠缺失如何影响心血管系统？

睡眠缺失对心血管系统有显著影响。例如，全球范围内的实验表明，夏令时开始时，人们失去一小时的睡眠，随后的24小时内心脏病发作的风险增加了24%。而在秋天，当我们获得额外的一小时睡眠时，心脏病发作的风险减少了21%。

为什么缺乏睡眠会导致免疫系统功能下降？

缺乏睡眠会导致免疫系统中自然杀伤细胞活性显著下降。自然杀伤细胞是免疫系统中的“秘密服务人员”，擅长识别和消除危险和不需要的元素。当睡眠不足时，自然杀伤细胞的活性会下降70%，这可能导致免疫系统功能不足，增加多种癌症的风险。

睡眠缺失如何影响我们的基因活动？

睡眠缺失会导致基因活动发生显著变化。研究发现，与充足睡眠的个体相比，睡眠不足的个体有711个基因的活动发生了扭曲，其中一半的基因活动减少，与免疫系统相关；另一半基因活动增加，与促进肿瘤、长期慢性炎症和压力相关的基因。

如何改善睡眠质量？

改善睡眠质量的建议包括保持规律的睡眠时间，无论是工作日还是周末，都在同一时间上床睡觉和起床。此外，保持卧室温度较低也有助于睡眠，目标是大约18摄氏度，因为身体需要降低核心温度以促进睡眠。

为什么说睡眠是生命的必需品？

睡眠是生命的必需品，因为它是我们生命的支持系统。睡眠不足会严重影响我们的健康、福祉、安全和儿童的教育。演讲者强调，睡眠不应被视为可选的生活方式奢侈，而是不可谈判的生物需求。

如果晚上辗转反侧无法入睡，应该怎么办？

如果在床上辗转反侧无法入睡，应该起床去另一个房间做其他事情，打破大脑将卧室与清醒状态联系在一起的习惯。只有当感到困倦时才回到床上，这样可以重新学习床是睡眠的地方的关联。

Outlines

00:00

😴 睡眠与生殖健康

该段落讨论了睡眠对男性和女性生殖健康的影响。研究表明，每晚只睡四到五小时的男性，其睾丸明显小于睡眠七小时或以上的男性。此外，睡眠不足会导致男性体内睾丸激素水平降低至相当于年长10岁的人的水平。同样，女性因缺乏睡眠也会出现生殖健康问题。这引出了一个主题，即睡眠对健康的重要性，以及睡眠不足对大脑和身体的负面影响。

05:00

🧠 睡眠对学习和记忆的影响

本段内容强调了睡眠对学习和记忆功能的重要性。研究发现，睡眠不仅在新知识的学习后起到巩固记忆的作用，而且在学习前也至关重要，有助于准备大脑吸收新信息。缺乏睡眠会导致大脑的记忆回路受损，无法有效吸收新记忆。实验数据表明，整夜未睡的人与睡眠充足的人相比，在形成新记忆方面的能力有40%的下降。这强调了睡眠对教育人口的重要性，以及睡眠不足可能导致的学习障碍。

10:03

🌙 深度睡眠与记忆转移

这一段讨论了深度睡眠期间大脑中的神经活动，以及它们如何帮助记忆从短期存储转移到长期存储。深度睡眠期间的大脑波动和睡眠纺锤波对于记忆的巩固至关重要。研究还指出，随着年龄的增长，睡眠质量下降，特别是深度睡眠的质量，这与认知能力下降有关。阿尔茨海默病也与深度睡眠的破坏有关。但有希望的是，通过改善睡眠质量，可能有助于减缓认知衰退和阿尔茨海默病的发展。

15:03

💪 睡眠与身体健康

这部分内容探讨了睡眠对身体健康的全面影响。睡眠不足会影响生殖系统、心血管系统，甚至免疫系统。例如，全球范围内的实验表明，夏令时开始时，人们失去一小时的睡眠，心脏病发作率在次日增加24%。此外，睡眠不足与多种癌症风险增加有关，包括肠癌、前列腺癌和乳腺癌。世界卫生组织已将夜班工作列为可能的致癌因素。研究还发现，睡眠不足会改变基因活动，导致免疫系统相关基因活动降低，而与肿瘤促进、慢性炎症和压力相关的基因活动增加。

🕒 改善睡眠质量的建议

最后一段提供了改善睡眠质量的建议。避免酒精和咖啡因对睡眠的负面影响，白天避免打盹。建议保持规律的睡眠时间，无论是工作日还是周末。此外，保持卧室温度较低，大约18摄氏度，有助于更好地入睡和保持睡眠。强调了睡眠不是可选的生活方式，而是生物上的必要需求，对健康、幸福和公共安全至关重要。呼吁人们重视睡眠，改善睡眠习惯，以应对21世纪最大的公共卫生挑战之一——睡眠丧失。

Keywords

💡睡眠

睡眠是人体的一种自然生理现象，是恢复体力和精力、维持生命活动所必需的。在视频中，睡眠被强调为一种非可谈判的生物学需求，对学习、记忆、免疫系统、生殖系统以及整体健康有着深远的影响。

💡睾丸

睾丸是男性生殖系统的重要组成部分，负责产生精子和男性激素。视频中提到，每晚只睡五小时的男性睾丸体积显著小于睡眠七小时或以上的男性，说明了睡眠质量和时长对生殖健康的潜在影响。

💡睾酮

睾酮是一种主要由睾丸产生的男性激素，对男性的性特征、肌肉质量和骨密度等有重要作用。视频中提到，睡眠不足会导致睾酮水平下降，从而影响男性的健康和福祉。

💡记忆

记忆是大脑存储和回忆信息的能力，对学习和日常生活至关重要。视频中强调了睡眠对记忆巩固的重要性，说明了睡眠对于形成新记忆和保持已有记忆的作用。

💡海马体

海马体是大脑中与记忆形成密切相关的区域，常被比喻为大脑的信息收件箱。视频中提到，海马体在睡眠充足的人中显示出健康的学习相关活动，而在缺乏睡眠的人中则没有显著信号。

💡深度睡眠

深度睡眠是睡眠周期中的一个阶段，此时大脑会产生大而强烈的脑波，并伴随着睡眠纺锤波，有助于记忆从短期存储转移到长期存储。视频中强调了深度睡眠对记忆和学习能力的恢复和增强作用。

💡阿尔茨海默病

阿尔茨海默病是一种常见的神经退行性疾病，主要表现为记忆力减退、认知能力下降等症状。视频中提到，深度睡眠的破坏是导致认知衰退和记忆衰退的一个被低估的因素，与阿尔茨海默病的发展有关。

💡免疫系统

免疫系统是身体的防御机制，负责识别和清除病原体和有害物质。视频中提到，睡眠不足会导致免疫细胞活动下降，从而影响身体的免疫防御能力。

💡基因

基因是遗传物质的基本单位，决定了生物体的许多特征和功能。视频中提到，睡眠不足会导致基因活动发生显著变化，其中一些基因与免疫系统减弱、肿瘤促进、长期慢性炎症和压力相关的基因活动增加。

💡昼夜节律

昼夜节律是生物体内部的时钟，控制着睡眠-觉醒周期和其他生理过程。视频中提到，夜间轮班工作会破坏昼夜节律，被世界卫生组织归类为可能的致癌因素。

💡健康建议

健康建议是指为了维护和促进个人健康而提出的指导性意见。视频中提供了关于改善睡眠质量的建议，如保持规律的睡眠时间和保持卧室温度适中。

Highlights

睡眠时长与男性睾丸大小的关系

睡眠不足对男性睾丸激素水平的影响

睡眠不足对女性生殖健康的影响

睡眠对学习和记忆的重要性

睡眠对大脑吸收新信息的准备作用

睡眠剥夺对大脑记忆回路的影响

睡眠对大脑海马体的作用

睡眠对老年人认知能力和记忆力的影响

睡眠对阿尔茨海默病的潜在影响

睡眠对免疫系统的影响

睡眠不足与癌症风险的关联

睡眠不足对基因活动的影响

睡眠对心血管系统的影响

睡眠对日常健康的重要性

改善睡眠质量的建议

睡眠的必要性

Transcripts

Thank you very much.

Well, I would like to start with testicles.

(Laughter)

Men who sleep five hours a night

have significantly smaller testicles than those who sleep seven hours or more.

(Laughter)

In addition, men who routinely sleep just four to five hours a night

will have a level of testosterone

which is that of someone 10 years their senior.

So a lack of sleep will age a man by a decade

in terms of that critical aspect of wellness.

And we see equivalent impairments in female reproductive health

caused by a lack of sleep.

This is the best news that I have for you today.

(Laughter)

From this point, it may only get worse.

Not only will I tell you about the wonderfully good things

that happen when you get sleep,

but the alarmingly bad things that happen when you don't get enough,

both for your brain and for your body.

Let me start with the brain

and the functions of learning and memory,

because what we've discovered over the past 10 or so years

is that you need sleep after learning

to essentially hit the save button on those new memories

so that you don't forget.

But recently, we discovered that you also need sleep before learning

to actually prepare your brain,

almost like a dry sponge

ready to initially soak up new information.

And without sleep, the memory circuits of the brain

essentially become waterlogged, as it were,

and you can't absorb new memories.

So let me show you the data.

Here in this study, we decided to test the hypothesis

that pulling the all-nighter was a good idea.

So we took a group of individuals

and we assigned them to one of two experimental groups:

a sleep group and a sleep deprivation group.

Now the sleep group, they're going to get a full eight hours of slumber,

but the deprivation group, we're going to keep them awake

in the laboratory, under full supervision.

There's no naps or caffeine, by the way, so it's miserable for everyone involved.

And then the next day,

we're going to place those participants inside an MRI scanner

and we're going to have them try and learn a whole list of new facts

as we're taking snapshots of brain activity.

And then we're going to test them

to see how effective that learning has been.

And that's what you're looking at here on the vertical axis.

And when you put those two groups head to head,

what you find is a quite significant, 40-percent deficit

in the ability of the brain to make new memories without sleep.

I think this should be concerning,

considering what we know is happening to sleep

in our education populations right now.

In fact, to put that in context,

it would be the difference in a child acing an exam

versus failing it miserably -- 40 percent.

And we've gone on to discover what goes wrong within your brain

to produce these types of learning disabilities.

And there's a structure that sits

on the left and the right side of your brain, called the hippocampus.

And you can think of the hippocampus

almost like the informational inbox of your brain.

It's very good at receiving new memory files

and then holding on to them.

And when you look at this structure

in those people who'd had a full night of sleep,

we saw lots of healthy learning-related activity.

Yet in those people who were sleep-deprived,

we actually couldn't find any significant signal whatsoever.

So it's almost as though sleep deprivation had shut down your memory inbox,

and any new incoming files -- they were just being bounced.

You couldn't effectively commit new experiences to memory.

So that's the bad that can happen if I were to take sleep away from you,

but let me just come back to that control group for a second.

Do you remember those folks that got a full eight hours of sleep?

Well, we can ask a very different question:

What is it about the physiological quality of your sleep

when you do get it

that restores and enhances your memory and learning ability

each and every day?

And by placing electrodes all over the head,

what we've discovered is that there are big, powerful brainwaves

that happen during the very deepest stages of sleep

that have riding on top of them

these spectacular bursts of electrical activity

that we call sleep spindles.

And it's the combined quality of these deep-sleep brainwaves

that acts like a file-transfer mechanism at night,

shifting memories from a short-term vulnerable reservoir

to a more permanent long-term storage site within the brain,

and therefore protecting them, making them safe.

And it is important that we understand

what during sleep actually transacts these memory benefits,

because there are real medical and societal implications.

And let me just tell you about one area

that we've moved this work out into, clinically,

which is the context of aging and dementia.

Because it's of course no secret that, as we get older,

our learning and memory abilities begin to fade and decline.

But what we've also discovered

is that a physiological signature of aging is that your sleep gets worse,

especially that deep quality of sleep that I was just discussing.

And only last year, we finally published evidence

that these two things, they're not simply co-occurring,

they are significantly interrelated.

And it suggests that the disruption of deep sleep

is an underappreciated factor

that is contributing to cognitive decline or memory decline

in aging, and most recently we've discovered,

in Alzheimer's disease as well.

Now, I know this is remarkably depressing news.

It's in the mail. It's coming at you.

But there's a potential silver lining here.

Unlike many of the other factors that we know are associated with aging,

for example changes in the physical structure of the brain,

that's fiendishly difficult to treat.

But that sleep is a missing piece in the explanatory puzzle

of aging and Alzheimer's is exciting

because we may be able to do something about it.

And one way that we are approaching this at my sleep center

is not by using sleeping pills, by the way.

Unfortunately, they are blunt instruments that do not produce naturalistic sleep.

Instead, we're actually developing a method based on this.

It's called direct current brain stimulation.

You insert a small amount of voltage into the brain,

so small you typically don't feel it,

but it has a measurable impact.

Now if you apply this stimulation during sleep in young, healthy adults,

as if you're sort of singing in time with those deep-sleep brainwaves,

not only can you amplify the size of those deep-sleep brainwaves,

but in doing so, we can almost double the amount of memory benefit

that you get from sleep.

The question now is whether we can translate

this same affordable, potentially portable piece of technology

into older adults and those with dementia.

Can we restore back some healthy quality of deep sleep,

and in doing so, can we salvage aspects of their learning

and memory function?

That is my real hope now.

That's one of our moon-shot goals, as it were.

So that's an example of sleep for your brain,

but sleep is just as essential for your body.

We've already spoken about sleep loss and your reproductive system.

Or I could tell you about sleep loss and your cardiovascular system,

and that all it takes is one hour.

Because there is a global experiment performed on 1.6 billion people

across 70 countries twice a year,

and it's called daylight saving time.

Now, in the spring, when we lose one hour of sleep,

we see a subsequent 24-percent increase in heart attacks that following day.

In the autumn, when we gain an hour of sleep,

we see a 21-percent reduction in heart attacks.

Isn't that incredible?

And you see exactly the same profile for car crashes, road traffic accidents,

even suicide rates.

But as a deeper dive, I want to focus on this:

sleep loss and your immune system.

And here, I'll introduce these delightful blue elements in the image.

They are called natural killer cells,

and you can think of natural killer cells almost like the secret service agents

of your immune system.

They are very good at identifying dangerous, unwanted elements

and eliminating them.

In fact, what they're doing here is destroying a cancerous tumor mass.

So what you wish for is a virile set of these immune assassins

at all times,

and tragically, that's what you don't have if you're not sleeping enough.

So here in this experiment,

you're not going to have your sleep deprived for an entire night,

you're simply going to have your sleep restricted to four hours

for one single night,

and then we're going to look to see what's the percent reduction

in immune cell activity that you suffer.

And it's not small -- it's not 10 percent,

it's not 20 percent.

There was a 70-percent drop in natural killer cell activity.

That's a concerning state of immune deficiency,

and you can perhaps understand why we're now finding

significant links between short sleep duration

and your risk for the development of numerous forms of cancer.

Currently, that list includes cancer of the bowel,

cancer of the prostate and cancer of the breast.

In fact, the link between a lack of sleep and cancer is now so strong

that the World Health Organization

has classified any form of nighttime shift work

as a probable carcinogen,

because of a disruption of your sleep-wake rhythms.

So you may have heard of that old maxim

that you can sleep when you're dead.

Well, I'm being quite serious now --

it is mortally unwise advice.

We know this from epidemiological studies across millions of individuals.

There's a simple truth:

the shorter your sleep, the shorter your life.

Short sleep predicts all-cause mortality.

And if increasing your risk for the development of cancer

or even Alzheimer's disease

were not sufficiently disquieting,

we have since discovered that a lack of sleep will even erode

the very fabric of biological life itself,

your DNA genetic code.

So here in this study, they took a group of healthy adults

and they limited them to six hours of sleep a night

for one week,

and then they measured the change in their gene activity profile

relative to when those same individuals

were getting a full eight hours of sleep a night.

And there were two critical findings.

First, a sizable and significant 711 genes

were distorted in their activity,

caused by a lack of sleep.

The second result was that about half of those genes

were actually increased in their activity.

The other half were decreased.

Now those genes that were switched off by a lack of sleep

were genes associated with your immune system,

so once again, you can see that immune deficiency.

In contrast, those genes that were actually upregulated

or increased by way of a lack of sleep,

were genes associated with the promotion of tumors,

genes associated with long-term chronic inflammation within the body,

and genes associated with stress,

and, as a consequence, cardiovascular disease.

There is simply no aspect of your wellness

that can retreat at the sign of sleep deprivation

and get away unscathed.

It's rather like a broken water pipe in your home.

Sleep loss will leak down into every nook and cranny

of your physiology,

even tampering with the very DNA nucleic alphabet

that spells out your daily health narrative.

And at this point, you may be thinking,

"Oh my goodness, how do I start to get better sleep?

What are you tips for good sleep?"

Well, beyond avoiding the damaging and harmful impact

of alcohol and caffeine on sleep,

and if you're struggling with sleep at night,

avoiding naps during the day,

I have two pieces of advice for you.

The first is regularity.

Go to bed at the same time, wake up at the same time,

no matter whether it's the weekday or the weekend.

Regularity is king,

and it will anchor your sleep

and improve the quantity and the quality of that sleep.

The second is keep it cool.

Your body needs to drop its core temperature

by about two to three degrees Fahrenheit to initiate sleep

and then to stay asleep,

and it's the reason you will always find it easier

to fall asleep in a room that's too cold

than too hot.

So aim for a bedroom temperature of around 65 degrees,

or about 18 degrees Celsius.

That's going to be optimal for the sleep of most people.

And then finally, in taking a step back, then,

what is the mission-critical statement here?

Well, I think it may be this:

sleep, unfortunately, is not an optional lifestyle luxury.

Sleep is a nonnegotiable biological necessity.

It is your life-support system,

and it is Mother Nature's best effort yet at immortality.

And the decimation of sleep throughout industrialized nations

is having a catastrophic impact on our health, our wellness,

even the safety and the education of our children.

It's a silent sleep loss epidemic,

and it's fast becoming one of the greatest public health challenges

that we face in the 21st century.

I believe it is now time for us to reclaim our right

to a full night of sleep,

and without embarrassment

or that unfortunate stigma of laziness.

And in doing so, we can be reunited with the most powerful elixir of life,

the Swiss Army knife of health, as it were.

And with that soapbox rant over,

I will simply say, good night, good luck,

and above all ...

I do hope you sleep well.

Thank you very much indeed.

(Applause)

Thank you.

(Applause)

Thank you so much.

David Biello: No, no, no. Stay there for a second.

Good job not running away, though. I appreciate that.

So that was terrifying.

Matt Walker: You're welcome. DB: Yes, thank you, thank you.

Since we can't catch up on sleep, what are we supposed to do?

What do we do when we're, like, tossing and turning in bed late at night

or doing shift work or whatever else?

MW: So you're right, we can't catch up on sleep.

Sleep is not like the bank.

You can't accumulate a debt

and then hope to pay it off at a later point in time.

I should also note the reason that it's so catastrophic

and that our health deteriorates so quickly,

first, it's because human beings are the only species

that deliberately deprive themselves of sleep

for no apparent reason.

DB: Because we're smart.

MW: And I make that point because it means that Mother Nature,

throughout the course of evolution,

has never had to face the challenge of this thing called sleep deprivation.

So she's never developed a safety net,

and that's why when you undersleep,

things just sort of implode so quickly, both within the brain and the body.

So you just have to prioritize.

DB: OK, but tossing and turning in bed,

what do I do?

MW: So if you are staying in bed awake for too long,

you should get out of bed and go to a different room

and do something different.

The reason is because your brain will very quickly associate your bedroom

with the place of wakefulness,

and you need to break that association.

So only return to bed when you are sleepy,

and that way you will relearn the association that you once had,

which is your bed is the place of sleep.

So the analogy would be,

you'd never sit at the dinner table, waiting to get hungry,

so why would you lie in bed, waiting to get sleepy?

DB: Well, thank you for that wake-up call.

Great job, Matt.

MW: You're very welcome. Thank you very much.