Three and a half years ago, I made one of the best decisions of my life. As my New Year's resolution, I gave up dieting, stopped worrying about my weight, and learned to eat mindfully. Now I eat whenever I'm hungry, and I've lost 10 pounds.
三年半前, 我做了一個人生中最正確的決定。 過年要有新決心 我決定放棄減肥,不再擔心自己的體重 而是吃東西的時候留心一些 現在,我餓了就吃飯 而且我已經減掉了10磅(4.5公斤)
This was me at age 13, when I started my first diet. I look at that picture now, and I think, you did not need a diet, you needed a fashion consult. (Laughter) But I thought I needed to lose weight, and when I gained it back, of course I blamed myself. And for the next three decades, I was on and off various diets. No matter what I tried, the weight I'd lost always came back. I'm sure many of you know the feeling.
這是十三歲的我,第一次減肥 這是十三歲的我,第一次減肥 現在看著這張照片,我會想 “你不需要減肥” “你倒該去找個時尚顧問…” (笑) 但當時我認為自己需要減肥, 當減掉的體重又回來之後 但當時我認為自己需要減肥, 當減掉的體重又回來之後 我全都怪在自己身上。 在接下來的三十多年裡, 我一次次地嘗試各種減肥法。 不管我怎麼做, 減掉的重量最後總是長回來。 不管我怎麼做, 減掉的重量最後總是長回來。 肯定有不少人理解這種感覺。
As a neuroscientist, I wondered, why is this so hard? Obviously, how much you weigh depends on how much you eat and how much energy you burn. What most people don't realize is that hunger and energy use are controlled by the brain, mostly without your awareness. Your brain does a lot of its work behind the scenes, and that is a good thing, because your conscious mind -- how do we put this politely? -- it's easily distracted. It's good that you don't have to remember to breathe when you get caught up in a movie. You don't forget how to walk because you're thinking about what to have for dinner.
作為一個神經學家, 我很好奇為什麼減肥如此困難? 很明顯,體重取決於 “吃多少食物”和“消耗多少能量” 很明顯,體重取決於 “吃多少食物”和“消耗多少能量” 而大多數人沒有意識到, 飢餓感和能量的消耗,是由大腦控制的。 飢餓感和能量的消耗,是由大腦控制的。 而基本上和意識無關。 大腦把很多事情放在“幕後”自動處理, 這是好事,因為你的“意識”── 這是好事,因為你的“意識”── ──怎麼把話說得好聽點呢?── 注意力很容易分散。 比如看電影的時候, 你不用怕自己忘記呼吸怎麼辦。 比如看電影的時候, 你不用怕自己忘記呼吸怎麼辦。 在考慮晚餐吃什麼的時候, 你不會忘了怎麼走路。 在考慮晚餐吃什麼的時候, 你不會忘了怎麼走路。
Your brain also has its own sense of what you should weigh, no matter what you consciously believe. This is called your set point, but that's a misleading term, because it's actually a range of about 10 or 15 pounds. You can use lifestyle choices to move your weight up and down within that range, but it's much, much harder to stay outside of it. The hypothalamus, the part of the brain that regulates body weight, there are more than a dozen chemical signals in the brain that tell your body to gain weight, more than another dozen that tell your body to lose it, and the system works like a thermostat, responding to signals from the body by adjusting hunger, activity and metabolism, to keep your weight stable as conditions change. That's what a thermostat does, right? It keeps the temperature in your house the same as the weather changes outside. Now you can try to change the temperature in your house by opening a window in the winter, but that's not going to change the setting on the thermostat, which will respond by kicking on the furnace to warm the place back up. Your brain works exactly the same way, responding to weight loss by using powerful tools to push your body back to what it considers normal. If you lose a lot of weight, your brain reacts as if you were starving, and whether you started out fat or thin, your brain's response is exactly the same. We would love to think that your brain could tell whether you need to lose weight or not, but it can't. If you do lose a lot of weight, you become hungry, and your muscles burn less energy. Dr. Rudy Leibel of Columbia University has found that people who have lost 10 percent of their body weight burn 250 to 400 calories less because their metabolism is suppressed. That's a lot of food. This means that a successful dieter must eat this much less forever than someone of the same weight who has always been thin.
大腦對體重也有自己的一套想法, 大腦對體重也有自己的一套想法, 不論你的“意識”是怎麼想的。 這被稱為你的“固定值“, 但這個名字有點誤導視聽, 準確來說,這個數值 可以自由浮動約10﹣15磅(約5-7kg) 準確來說,這個數值 可以自由浮動約10﹣15磅(約5-7kg) 生活方式的改變, 會在這個範圍內影響你的體重。 生活方式的改變, 會在這個範圍內影響你的體重。 但想在這個範圍以外,就非常困難了。 在下丘腦,你大腦調節體重的部份, 在下丘腦,你大腦調節體重的部份, 有十多種化學信號控制著”體重的增加“, 有十多種化學信號控制著”體重的增加“, 另外還有十多種化學信號, 控制著”體重的減少“。 這整個系統就像是個恒溫器, 對身體的刺激作出反應, 調整飢餓感,活動量和新陳代謝, 在不同環境下,維持你的體重。 恒溫器就是這樣工作的,不是麼? 恒溫器確保室內溫度 總是保持在一定範圍內 不管外面的天氣怎麼變化。 你可以在冬天打開窗戶,來調節室內溫度, 你可以在冬天打開窗戶,來調節室內溫度, 但這不會改變恒溫器的設定。 於是它做出反應,啟動暖爐加熱整個房間。 於是它做出反應,啟動暖爐加熱整個房間。 減肥的時候,你的大腦也會做出一樣的反應, 減肥的時候,你的大腦也會做出一樣的反應, 用非常規的手段, 把身體調整到”它“認為合適的狀態。 用非常規的手段, 把身體調整到”它“認為合適的狀態。 如果你一口氣減掉很多重量, 你的大腦會認為你快餓死了, 不論一開始是胖是瘦,大腦的反應都是一樣的。 不論一開始是胖是瘦,大腦的反應都是一樣的。 我們當然希望大腦 可以判斷本人是否想要減肥 我們當然希望 大腦可以判斷本人是否想要減肥 但它辦不到。 如果你一口氣減掉很多, 你會感到飢餓, 你的肌肉消耗的能量也一起下降。 哥倫比亞大學的Rudy Leibel教授 發現那些減少過10%體重的人, 發現那些減少過10%體重的人, 每天少消耗250﹣400卡路里 因為他們的新陳代謝被壓抑了。 那相當於一頓大餐了。 這就是說,減肥成功的人 必須從此以後每天少吃這麼一頓大餐 才能趕上那些不用減肥, 也一直是這個體重的人。 才能趕上那些不用減肥, 也一直是這個體重的人。
From an evolutionary perspective, your body's resistance to weight loss makes sense. When food was scarce, our ancestors' survival depended on conserving energy, and regaining the weight when food was available would have protected them against the next shortage. Over the course of human history, starvation has been a much bigger problem than overeating. This may explain a very sad fact: Set points can go up, but they rarely go down. Now, if your mother ever mentioned that life is not fair, this is the kind of thing she was talking about. (Laughter) Successful dieting doesn't lower your set point. Even after you've kept the weight off for as long as seven years, your brain keeps trying to make you gain it back. If that weight loss had been due to a long famine, that would be a sensible response. In our modern world of drive-thru burgers, it's not working out so well for many of us. That difference between our ancestral past and our abundant present is the reason that Dr. Yoni Freedhoff of the University of Ottawa would like to take some of his patients back to a time when food was less available, and it's also the reason that changing the food environment is really going to be the most effective solution to obesity.
從進化的角度來說, 身體對於”減肥“的抵抗性是有理由的。 因為我們的祖先, 在食物匱乏的時候必須節約體能, 因為我們的祖先, 在食物匱乏的時候必須節約體能, 而在食物充沛時儘快補回失去的分量, 才能抵禦下一次饑荒。 縱觀歷史, 食物短缺一直比超重要嚴重得多。 食物短缺一直比超重要嚴重得多。 這解釋了一個令人難過的事實: 體重的”固定值“可能上升, 但幾乎不會下降。 如果媽媽曾經告訴你們, 世上有很多不公平的事, 這肯定就是其中之一了。(笑) 這肯定就是其中之一了。(笑) 減肥成功不會降低你的”固定值“。 就算你保持體重減輕整整七年 就算你保持體重減輕整整七年 你的大腦也依然會試圖把體重增回來。 如果體重減輕是因為長期饑荒 那這種反應也無可厚非。 而在快餐橫行的現代社會, 這套反應機制就不太妙了。 古老的過去,和富足的現代之間的差別 古老的過去,和富足的現代之間的差別 正是渥太華大學的Yoni Freedhoff博士 為什麼會開玩笑說, 他想把一些病人送回食物不充足的時代, (“給我一台時光機, 我就給你全世界最好的減肥計劃”) 他想把一些病人送回食物不充足的時代, (“給我一台時光機, 我就給你全世界最好的減肥計劃”) 他想把一些病人送回食物不充足的時代, (“給我一台時光機, 我就給你全世界最好的減肥計劃”) 這也是為什麼,飲食環境的改變 才是應對肥胖最有效的措施。 這也是為什麼,飲食環境的改變 才是應對肥胖最有效的措施。 這也是為什麼,飲食環境的改變 才是應對肥胖最有效的措施。
Sadly, a temporary weight gain can become permanent. If you stay at a high weight for too long, probably a matter of years for most of us, your brain may decide that that's the new normal.
可惜的是,一時的增重, 可能變成永久的增重。 如果超重的狀態保持太久, 對大多數人大概幾年左右, 你的大腦可能會決定說,那才是新的”固定值“。
Psychologists classify eaters into two groups, those who rely on their hunger and those who try to control their eating through willpower, like most dieters. Let's call them intuitive eaters and controlled eaters. The interesting thing is that intuitive eaters are less likely to be overweight, and they spend less time thinking about food. Controlled eaters are more vulnerable to overeating in response to advertising, super-sizing, and the all-you-can-eat buffet. And a small indulgence, like eating one scoop of ice cream, is more likely to lead to a food binge in controlled eaters. Children are especially vulnerable to this cycle of dieting and then binging. Several long-term studies have shown that girls who diet in their early teenage years are three times more likely to become overweight five years later, even if they started at a normal weight, and all of these studies found that the same factors that predicted weight gain also predicted the development of eating disorders. The other factor, by the way, those of you who are parents, was being teased by family members about their weight. So don't do that. (Laughter)
心理學家把”吃貨“分為兩類: 一種是餓了就吃 一種是試圖控制飲食, 也就是大部份減肥者的做法。 一種是試圖控制飲食, 也就是大部份減肥者的做法。 我們就叫他們”想吃就吃“和”自控地吃“吧。 有意思的是,”想吃就吃“的人 比較不容易超重, 這些人也不太去想吃的事。 自控的吃貨,反而容易受到諸如 廣告宣傳、超大分量、無限量自助餐 之類的誘惑和影響。 廣告宣傳、超大分量、無限量自助餐 之類的誘惑和影響。 小小的誘惑, 比如一勺冰淇淋, 更容易引起”自控型“的人去暴飲暴食。 更容易引起”自控型“的人去暴飲暴食。 青少年尤其容易陷入”減肥後暴食“的循環。 青少年尤其容易陷入”減肥後暴食“的循環。 一些長期調查研究顯示, 十幾歲時減過肥的女孩, 五年後超重的概率是普通人的三倍, 五年後超重的概率是普通人的三倍, 就算她們一開始時體重正常, 所有這些研究都顯示 一些因素在預測了超重的同時 一些因素在預測了超重的同時 也預測了”飲食障礙“。 另一個因素,順帶一提, 請家長們注意了, 是”被家庭成員嘲笑體重“這件事。 是”被家庭成員嘲笑體重“這件事。 所以拜託, 別這麼做了。(笑)
I left almost all my graphs at home, but I couldn't resist throwing in just this one, because I'm a geek, and that's how I roll. (Laughter) This is a study that looked at the risk of death over a 14-year period based on four healthy habits: eating enough fruits and vegetables, exercise three times a week, not smoking, and drinking in moderation. Let's start by looking at the normal weight people in the study. The height of the bars is the risk of death, and those zero, one, two, three, four numbers on the horizontal axis are the number of those healthy habits that a given person had. And as you'd expect, the healthier the lifestyle, the less likely people were to die during the study. Now let's look at what happens in overweight people. The ones that had no healthy habits had a higher risk of death. Adding just one healthy habit pulls overweight people back into the normal range. For obese people with no healthy habits, the risk is very high, seven times higher than the healthiest groups in the study. But a healthy lifestyle helps obese people too. In fact, if you look only at the group with all four healthy habits, you can see that weight makes very little difference. You can take control of your health by taking control of your lifestyle, even If you can't lose weight and keep it off.
我幾乎把圖表都留在家裡了, 不過我忍不住要給你們看這張圖, 因為我是個書蟲,沒圖表不舒服。(笑) 因為我是個書蟲,沒圖表不舒服。(笑) 這是一個持續了十四年 關於健康風險的研究 通過觀察平時的四個健康習慣: 攝入足夠的蔬果, 每週運動三次, 不吸菸, 適度飲酒。 我們先來看一看正常體重的人群吧 我們先來看一看正常體重的人群吧 柱子的高度,代表死亡率 橫軸的0,1,2,3,4 橫軸的0,1,2,3,4 代表研究對象有幾個健康習慣 代表研究對象有幾個健康習慣 你能猜得到,生活方式越健康, 人的死亡率也越低。 接著來看一下 超重的人的數據。 那些完全沒有健康習慣的人, 死亡率比較高。 僅僅是多了一個健康的習慣 就能把超重的人拉回到普通範圍裡。 對於沒有任何健康習慣的肥胖者(最右邊)而言, 死亡風險非常高, 整整比研究中最健康的人高出七倍。 死亡風險非常高, 整整比研究中最健康的人高出七倍。 但健康的生活方式對肥胖者也有好處。 實際上,如果你光看那些 四種健康習慣都具備的人, 你會發現,是胖是瘦關係不大。 如果想要健康的身體 控制生活習慣就可以了, 就算你沒辦法減掉體重也沒關係。 就算你沒辦法減掉體重也沒關係。
Diets don't have very much reliability. Five years after a diet, most people have regained the weight. Forty percent of them have gained even more. If you think about this, the typical outcome of dieting is that you're more likely to gain weight in the long run than to lose it.
減肥本身就不太可靠。 減肥後的五年內, 絕大部份人已經反彈了。 其中的40%甚至比之前更胖了。 想想看, 就會發現典型的減肥結果, 更可能是體重增加,而不是減少, 就長期而言。
If I've convinced you that dieting might be a problem, the next question is, what do you do about it? And my answer, in a word, is mindfulness. I'm not saying you need to learn to meditate or take up yoga. I'm talking about mindful eating: learning to understand your body's signals so that you eat when you're hungry and stop when you're full, because a lot of weight gain boils down to eating when you're not hungry. How do you do it? Give yourself permission to eat as much as you want, and then work on figuring out what makes your body feel good. Sit down to regular meals without distractions. Think about how your body feels when you start to eat and when you stop, and let your hunger decide when you should be done. It took about a year for me to learn this, but it's really been worth it. I am so much more relaxed around food than I have ever been in my life. I often don't think about it. I forget we have chocolate in the house. It's like aliens have taken over my brain. It's just completely different. I should say that this approach to eating probably won't make you lose weight unless you often eat when you're not hungry, but doctors don't know of any approach that makes significant weight loss in a lot of people, and that is why a lot of people are now focusing on preventing weight gain instead of promoting weight loss. Let's face it: If diets worked, we'd all be thin already. (Laughter) Why do we keep doing the same thing and expecting different results? Diets may seem harmless, but they actually do a lot of collateral damage. At worst, they ruin lives: Weight obsession leads to eating disorders, especially in young kids. In the U.S., we have 80 percent of 10-year-old girls say they've been on a diet. Our daughters have learned to measure their worth by the wrong scale. Even at its best, dieting is a waste of time and energy. It takes willpower which you could be using to help your kids with their homework or to finish that important work project, and because willpower is limited, any strategy that relies on its consistent application is pretty much guaranteed to eventually fail you when your attention moves on to something else.
如果我說的讓你信服了 說減肥可能有壞處 那麼下一個問題就是,你怎麼辦才好? 我的回答,籠統地說,就是”心平氣和”。 (mindfulness也指佛教的“正念”) 我不是讓你去坐禪冥想, 也不是瑜伽。 我指的是吃東西時留心一點: 試著觀察自己身體的信號, 餓了就吃,飽了就停, 餓了就吃,飽了就停, 因為很多時候體重的增加 是因為明明不餓還要吃。 具體怎麼做呢? 當你餓的時候,允許自己去吃東西, 接著想辦法弄清楚 怎樣讓身體處於舒適的狀態。 好好專心地坐下吃正餐。 開始吃和停止吃的時候, 想想看身體的感覺, 讓飢餓感來決定,到哪裡為止。 讓飢餓感來決定,到哪裡為止。 掌握這個尺度花了我大概一年的時間, 不過這很值得。 我不再像以前一樣, 現在即使旁邊放著食物,我也能放鬆下來。 我也不太去想吃的事情。 我會忘記房間里有塊巧克力。 就好像被外星人控制了我的大腦一樣。(笑) 完完全全不一樣了。 當然我要說一句, 通過這種途徑,基本上不會讓你瘦下來 常常不餓就吃東西那是另一回事。 但是對很多人來說,關於“怎樣才能減輕體重”, 醫生也無法給出明確地答案, 這也是為什麼今天很多人關注的是 如果預防肥胖, 而不是到處宣傳減肥。 面對現實吧: 要是減肥真的有用,我們早就瘦下來了(笑) 要是減肥真的有用,我們早就瘦下來了(笑) 為什麼我們一次又一次做著同樣地事情 卻期待不同的結果呢? 減肥看似無害, 但其實附帶了很多傷害 最壞的情況,會損害健康: 太過執著於體重會導致飲食障礙, 特別是青少年人群。 在美國,80%的10歲女童 說自己曾減過肥。 我們的女兒們在 用錯誤的價值觀衡量自己。 我們的女兒們在 用錯誤的價值觀衡量自己。 即便是最好的情況, 減肥也要浪費很多時間和精力。 減肥佔用了意志力 ──這些原本可以用在其他地方── 比如輔導自己的孩子做功課, 或者完成重要的工作, 又因為意志力是有限的, 而任何減肥的策略 都會持續地消耗意志力 這基本上保證了, 一旦注意力轉移到其他地方時 飢餓就會趁虛而入。
Let me leave you with one last thought. What if we told all those dieting girls that it's okay to eat when they're hungry? What if we taught them to work with their appetite instead of fearing it? I think most of them would be happier and healthier, and as adults, many of them would probably be thinner. I wish someone had told me that back when I was 13.
讓我最後再說一點, 如果我們告訴那些減肥中的女孩 “沒關係的,你想吃的時候就吃” 怎麼樣? 如果我們告訴她們,與其害怕自己的胃口 不如學會和它和平相處? 我覺得大部份女孩都會變得更快樂,更健康, 當她們成年後, 不少人可能會變得苗條起來吧。 我多希望自己十三歲的時候, 有人能這樣告訴我。
Thanks.
謝謝。
(Applause)
(鼓掌)