Mads Tang-Christensen: The brain science of obesity | TED

Transcriber:

Translator: Milly Pang Reviewer: Thomas Tam

Have you ever wondered why a pair of siblings

你是否好奇有兩個兄弟姊妹

living in the same house with the same parents,

同埋父母，大家住埋一齊

with the same food,

食嘅嘢又一樣

sometimes end up in opposite sides of the weight spectrum?

但有時佢哋嘅體重各走極端

My name is Mads

我係 Mads

and for the last 25 years,

喺過去 25 年

I've been studying what we eat, when we eat and how much we eat.

我一直喺度研究人食啲乜嘢 幾時食、同埋食幾多

And probably more importantly,

最重要嘅係

I've been studying how each of our unique bodies

我喺致力研究個別唔同嘅身體

responds differently to the same food and the same environment.

點樣喺相同嘅食物同埋環境度 做出不同嘅反應

To be more precise, I study obesity.

準確啲嚟講我研究肥胖症

During my training as an MD, PhD,

當我喺醫學同博士學位課程度

I was very fascinated by a series of experiments done by Barry Levin.

我愛上 Barry Levin 做嘅一連串實驗

He took 100 rats and subjected them to high-fat feeding.

佢餵一百隻老鼠食高脂肪嘅食物

After months of feeding,

餵咗幾個月

he ended up with a bell-shaped curve

得到嘅數據出現鐘形曲線

and a weight distribution

同唔同分佈嘅重量

with some skinny rats and some obese rats

分別有骨瘦如柴、過肥 同一啲體重適中嘅老鼠

and some in the middle.

What he then did was to take the skinny rats

接住佢將呢啲瘦嘅老鼠

and breed them among themselves,

放埋一齊繁殖後代

and the heavy rats.

嗰啲肥老鼠 都集中埋一齊繼續繁殖

And he bred those among themselves.

And after rounds of breeding, he ended up with two distinct populations:

經過幾輪繁殖 出現兩個極大差異嘅老鼠群：

a diet-resistant rat

一類老鼠抗拒飲食

and an obesity-prone rat.

另一類就好易肥胖

And here's the really interesting part.

呢個就係有趣嘅部分

Then he took the skinny or the obese,

之後佢將啲瘦嘅同肥嘅老鼠

and either massively over- or underfed them.

一係大量餵食，或者畀好少佢哋食

And their weight would, of course, go up and down

要視乎佢哋嘅飲食計劃 佢哋嘅體重會增加或減少

depending on the dietary regimen.

But it was as if the little bodies would remember the same old weight trajectory.

但係好似呢啲小動物 都會記得以前自己嘅重量

So once the dietary regimen was stopped,

當飲食計劃終止咗之後

the rats went right back to the initial weight trajectory.

佢哋嘅體重就回復到以前一樣

It was like as if you could dress up the obese rat

呢啲就好似肥老鼠嘅服飾

in a skinny sheep's clothing.

穿一身細碼嘅衫

But the obese rat nature was still scratching to get out.

但係佢哋嘅本性仲係想掙爆件衫

The same thing applies to humans.

呢啲理論同樣適用喺人身上

If you take a thousand kids and weigh them,

如果你同一千個細路磅下

their weight will also be distributed in a bell-shaped curve.

佢哋嘅重量亦都同樣呈現鐘型嘅分佈

Some skinny, some in the middle and some heavy.

有啲瘦削，有啲適中，有啲就偏重

We know that some of the skinny kids will remain skinny throughout life,

我哋知道一啲瘦削嘅細路 喺以後都會一直維持咁嘅身型

and some of the obese kids will stay obese throughout life.

同樣嗰啲肥細路 佢哋嘅體型都唔會改變

You could argue that their weight, to some degree, has been predetermined.

你可能會講佢哋嘅體重 某程度上係註定嘅

You could also argue that obesity is a disease.

你亦都可以講，肥胖係一種疾病

Wait, did I just say that obesity a disease?

咪住，我係咪講肥胖係種疾病啦？

Yes.

係嘅

There's actually data and science that shows that.

呢啲都係科學同數據所顯示出嚟

And I've made it my audacious life goal to come up with a solution

我亦大膽將我嘅人生目標 定為搵到解決方案

to prevent, treat or even cure obesity.

去預防，治療甚至醫好肥胖症

Let me explain.

等我講清楚

In the early 1980s and 1990s,

喺 20 世紀， 80 同 90 年代

obesity was considered a potential global problem,

肥胖係一個全球潛在嘅問題

a global problem of a magnitude

呢個全球問題之大

that led WHO in the end of 1990s

促使世界衛生組織係 90 年代尾

to declare obesity a global pandemic.

將肥胖定性為全球嘅大流行病

And I probably don't have to tell you why.

原因都唔使我講啦

Higher rates of diabetes, hypertension, cardiovascular disease, even some cancers,

越嚟越多人患有糖尿病、高血壓

心血管疾病、甚至癌症、關節炎，

osteoarthritis and a clear link to mental conditions such as depression.

都同抑鬱症嗰類精神狀況有直接關係

So as the number of obese individuals grew,

由於有越嚟越多人變得肥胖

so did the number of people suffering from these diseases.

呢啲人患上以上所講嘅疾病 機會會越大

Today, more than 50 percent of the US adult population

喺今日美國社會超過一半嘅成人人口

are living with obesity or overweight.

唔係肥胖就係超重

From a health perspective, that is devastating.

從健康角度嚟講係慘不忍睹

But it's not only a US problem.

但呢個唔係單單美國嘅問題

The obesity surge has made obesity a global health problem.

世界肥胖人口增多 令肥胖成為全球嘅健康問題

Many inside and outside the medical community

好多醫學界嘅行內同行外人士

believe obesity is not a disease.

都認為肥胖唔係一種疾病

They believe that obesity is a condition,

佢哋認為肥胖只係一種狀態

a condition brought about by too much eating

一種因為進食過量而產生嘅狀態

亦都係運動量太少所引起

and too little exercise.

As a matter of fact, a lot of people living with obesity think that too.

事實上，好多肥胖嘅人都同意

They believe that their weight is 100 percent their own fault,

佢哋認為超重，完全係自己嘅問題

which can lead to self-blame and low self-esteem,

咁樣會導致自己責備自己 令到自尊心低落

and perhaps even shame or stress eating,

甚至由於羞愧或者壓力而暴飲暴食

which is both heartbreaking, as well as counterproductive.

呢啲都會令人擔心，係識得其反嘅效果

But where is the scientific proof that obesity is a disease?

但有科學證據證明肥胖係病嗎？

Well, medically speaking, there's many ways to define disease,

其實從醫學角度嚟講 有好多方式去定義疾病呢樣嘢

but let me give you just three examples.

等我舉三個例子

As a process that impairs your functionality

一個損壞身體功能嘅過程

and reduces life expectancy -- obesity, check.

同埋縮短壽命—— 肥胖正係

You can define disease as a process

你可以定義疾病為一種過程

that leaves you more susceptible to other diseases or causes disease.

令你更易感染或引發其他疾病

Obesity, check.

肥胖就係

Or you can define disease as a genetic impairment

或者你可以定義疾病為由於一種基因缺憾

that leads to functional impairment,

導致功能性嘅損傷

like, for instance, a duplication of genes on chromosomes.

比如喺染色體嘅基因複製

有確鑿證據顯示

There is clear evidence

that a single gene mutation can lead to obesity,

單一嘅細胞變異會導致肥胖

such as, for instance, leptin deficiency and POMC deficiency.

例如缺乏瘦素同阿黑皮素原

We also have two-three genes leading to obesity.

仲有兩到三種基因會導致肥胖

And it's my prediction that we, by the year 2030,

我預測到 2030 年

will be able to explain most obesity by the genetic makeup of the individual.

我哋能通過個人身體嘅遺傳組合 去解釋肥胖嘅謎團

So obesity as a disease by this measure, check.

呢個角度嚟講肥胖正係一種疾病

我要講清楚嘅係

Let me be clear.

We humans have had the same genes for decades.

咁多年嚟我哋嘅基因都冇改變過

And just recently, obesity has become a bigger problem.

只係最近肥胖成為一種嚴重嘅問題

How do we then explain that?

我哋可點解釋呢？

One obvious thing is actually food, especially calorie-rich food,

最明顯係食物，尤其係高熱量嘅食物

which is much more readily available.

係垂手可得

It's relatively easy and also relatively cheap

佢哋相對容易得到，價格亦都較平

to eat your entire daily need of calories by a fast food or big soft drinks.

使到每日嘅熱量 由快餐同埋大杯汽水取得

So genes do play a role,

基因雖然有佢嘅作用

but the environment also plays a huge role.

但係環境扮演住重要嘅角色

The overabundance of calories in certain communities

某啲群體過剩嘅身體熱量

is a relatively new thing,

係相對較新穎嘅議題

and our genes haven't quite adapted yet.

而且我哋嘅基因仲未適應

In the history of feast and famine,

喺豐盛飲食同饑荒嘅歷史度

genetic selection has prepared us much better for famine,

基因嘅選擇幫助我哋應對饑荒

and for good reason.

呢個係有原因嘅

Starvation is bad,

挨餓係唔好嘅

but you could also argue obesity is bad.

但你亦可以反駁肥胖都係唔好嘅

And if obesity is a disease,

如果肥胖係一種疾病

how do we then prevent, treat or even cure it?

我哋要點樣預防、治療、甚至醫好佢呢？

I believe that the brain holds the key.

我認為大腦係一個關鍵

I have always been fascinated

佢一直吸引住我

with how small electrical signals in discrete parts of the brain

分散喺大腦各處有好多細小嘅電訊號

lead to big behavioral changes.

形成大嘅行為變化

And my study of the brain led me to Glucagon-Like Peptide 1,

我對大腦嘅研究 等我留意到類升糖素胜肽 1

or GLP-1 for short.

或簡稱 GLP-1

GLP-1 is a hormone and a signal molecule

GLP-1 係荷爾蒙同信號分子

that is produced both in the gut and in the brain.

佢喺大腦同腸道內形成

The brain speaks to the gut and the gut speaks to the brain.

大腦同腸道互相呼應，溝通緊密

Yes, that's right.

冇錯

Your belly and your brain are literally connected.

你嘅肚皮同大腦確實係相連嘅

Our research led us to see that GLP-1 has an effect on nerve cells

我哋嘅研究顯示 GLP-1 喺神經細胞係有效果嘅

sitting in areas that control whether we eat or not.

佢停留喺大腦控制住我哋食慾嘅位置

So, for instance, if we increase the level of GLP-1,

比如講，如果我哋增加 GLP-1 嘅量

the body's desire to eat or overeat food gets turned off.

就會降低啲人想進食或者過量進食嘅慾望

GLP-1 serves as the full signal in your car's gas tank.

GLP-1 就好比車嘅油箱裝滿嘅信號

I've spent years and decades mapping the circuitry of GLP-1

我花咗好多年時間 研究繪製 GLP-1 電路圖

and how GLP-1 interacts with other signal molecules and hormones.

GLP-1 點樣 同其他信號分子同荷爾蒙互動

All of these things go together and control food intake,

呢啲合埋一齊控制住食物嘅攝取

body weight and the control of eating behavior.

體重以及控制飲食嘅習慣

And what does that all mean?

咁樣意味住啲咩嘢？

Well, today, we have engineered and studied the molecule,

而家我哋已經研究同製造咗份子嘅結構

so we now have a molecule

所以我哋有咗一個分子 可以令到體重顯著下降

that can lead to a significant weight loss.

Obviously, GLP-1 is not the whole answer.

好明顯 GLP-1 並未能畀出完整嘅答案

We and others have discovered numerous hormones

我哋同其他科學家發現咗多種荷爾蒙

and other signal molecules

同其他信號分子

that are also pivotal for the regulation of food intake and body weight.

對控制飲食同埋體重呈現關鍵嘅作用

And it may end up

到最後

that these signal molecules and hormones are even more important than GLP-1.

呢啲信號分子同荷爾蒙 比起 GLP-1 更為重要

So ...

所以

There's plenty for us to do.

我哋有好多嘢要做

There's still plenty for us to explore.

仲有好多嘢要探索

So this is not the end.

所以而家並唔係終結

It's not even the beginning to the end.

甚至對盡頭仲未有頭緒

But perhaps this may be the end to the beginning.

或者只係初階段嘅結束

We may have a massive weight crisis on the planet today,

今日嘅世界可能有嚴重嘅體重問題

but the good news is we are on the right path.

但好消息係，我哋喺正確嘅方向

We now have solutions for people living with obesity,

可以為肥胖嘅人提供解決方案

and the next steps will be to understand even better

下一步將係更好嘅了解

the problems people living with obesity are facing.

肥胖嘅人所要面對嘅問題

To understand even better how genes and environment play together.

更好咁了解基因同環境點樣配合

And understand, finally, how all these things come together

同所有呢啲點樣一齊

and determine our body weight.

速成我哋嘅體重

Then, and maybe just then,

或者以後

we will be able to come up with a prevention,

我哋能夠搵到預防

a treatment or even a cure

治療、或者甚至治愈嘅方法

for people living with obesity,

畀肥胖嘅人

like we strive for with any other chronic disease.

就好似我哋致力研究其他慢性疾病咁

And this -- this still remains our audacious life’s goal.

而且呢啲仍然係我哋重要嘅人生目標

Thank you.

多謝大家！