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.

三年半前我做了人生中最棒的一个决定作为新年的新决心我放弃了节食， 停止了对自己体重的忧虑我开始谨慎地对待进食现在，只要我饿了我就吃我甚至还减了10磅 （约为4.55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.

这是我13岁时候的样子那是我开始第一次节食现在我看着这张照片，我想我需要的不是节食而是一名时尚顾问（笑声）但当时我认为自己需要减肥当我体重反弹回来的时候我感到自责在接下来的三十年里我开始又结束了各式各样的节食无论我采取怎样的努力我减去的体重总会反弹回来我确信你们中的很多人能体会到这感觉。

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.

作为一名神经科学家我很疑惑，为什么这如此困难？很显然，你的重量决定于你吃了多少和你消耗了多少能量但绝大部分人没有意识到的是饥饿和消耗是由大脑掌控的大多数情况下你甚至不会意识到你的大脑在后台做了很多事这很好因为你的意识让我想个更有礼貌的说法—-很容易被分散当你专注于电影的时候你不需要记得呼吸 亦可自由畅快地呼吸你不会因为思考晚餐吃什么而忘记如何行走。

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 weightwho has always been thin.

你的大脑对于你的体重有着自己的一套想法无论你有意识地在想些什么这被叫做你的设定值但那是个误导人的术语因为事实上它是一个范围大约在10到15磅内浮动你可以通过选择生活方式来改变你的体重在这个范围内上下浮动但是如果要超出这个范围 将是非常非常困难的大脑的一个部分叫下丘脑它调节着你的体重你的大脑有十多种化学信号会告诉你的身体去增加体重还有另外十多种信号会告诉你的身体去减重，这系统的工作原理就像恒温器对身体接收到的信号做出反应通过调节饥饿感，活动，新陈代谢根据条件的变化，维持你的体重这就是恒温器的作用，对吧？恒温器会根据房屋外部天气的变化不断调节从而保持室内的温度恒定现在你可以通过在冬季打开一扇窗来调节室内的温度但这个动作并不会改变恒温器的设置恒温器对此的反应是打开火炉把屋内的温度调节回温暖的状态你的大脑就是这样工作的当你体重减轻的时候它会用有效地工具让你的体重回归回归到它认为正常的状态如果你减重过多你大脑的反应就是你快饿死了无论你最初是胖还是瘦大脑的反应都是一模一样的我们非常希望我们的大脑可以感知我们是否需要减重但它不能如果你真的减去了很多体重你会感到很饿你的肌肉会消耗更少的能量哥伦比亚大学的鲁迪利贝尔博士发现那些减去体重10%的人们消耗的热量比未减重之前少250到400卡路里因为他们的新陈代谢被抑制了这些（热量）等于相当多的食物中所含的热量这意味着一个成功的节食者必须比和他相同体重的人少吃这么多食物因为这个人一直都这么瘦。

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.

从进化的角度上讲人的身体对于减重的抵制情有可原当食物匮乏时，我们的祖先依靠身体中储存的能量生存当食物充足时增加体重将会确保他们在下一次 食物短缺的情况下能够生存下来在人类历史进程中饥饿一直是比吃撑更大的问题这说明了一个非常可悲的事实设定值可以增加但几乎不会减少现在如果你妈妈跟你说生活很不公平这就是她所说的情形（笑声）节食成功并不会降低设定值即便是你已经减轻体重长达七年之久你的大脑一直会让你把减掉的体重增回来如果减重是由长时间饥饿造成的这是合情合理的反应在充斥着得来速汉堡的现代世界这种反应并不适用于大多数人过去我们祖先的生活和现代人富足的生活的差异是渥太华大学的约尼 弗雷德霍夫 博士想让他的一些病人回到食物不充足年代的原因这也是为什么改变饮食环境将成为解决肥胖问题最有效的方法。

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.

不幸的是，短暂的增重可变为永久的增重如果你长时间处于超重状态对于我们大多数人来说可能是若干年你的大脑就会觉得这是新的正常状态。

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)

心理学家把“吃货”分成两类一类人靠本能的饥饿反应去吃另一类人则是用意志去控制饮食就像大多数节食者一样我们称他们为本能型食着和自控型食者有趣的是本型能食者很少会超重并且他们会花较少的时间思考吃什么东西自控型食者则更容易受到广告，超大分量和自助餐的影响而造成饮食过量一个小小的放纵比如一勺冰激凌更有可能在自控型食者中导致暴饮暴食的结果在这种节食和暴饮暴食的循环下孩子们特别容易受到伤害一些长期研究表明在青少年初期节食的女孩在五年之后超重的可能性是未节食者的三倍即便她们一开始体重正常所有这些研究发现预示体重增加的因素也预示着饮食失调的产生顺便说一下请家长们注意了另外一个因素是“因体重而被家庭成员取笑”所以别那样做（笑声）。

7:26I 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.

我几乎把我所有的图表放家里了但我就是无法抗拒想要拿出这张图因为我是个书虫，没图表不舒服（笑声）下面我要讲的是一个进行了14年的有关四种健康习惯与死亡风险的研究吃足够的水果和蔬菜一个星期锻炼三次不吸烟饮酒节制我们来看看在研究当中体重正常的人柱状图的高表示死亡风险水平坐标上的数字0、1、2、3、4表示一个特定的人拥有健康习惯的个数你们的预期是，生活习惯越健康研究中人们死亡的可能性越小现在我们看看在超重者身上会发生什么那些没有任何一个健康习惯的人有更高的死亡风险仅仅增加一个健康的习惯就会让超重的人回到正常范围对于那些没有健康习惯的肥胖者这种风险极高，比那些在研究中最健康的一群人高七倍但是健康的生活方式也能帮助肥胖的人事实上，如果你只看有四种健康习惯的组你会发现体重无关紧要你可以通过控制生活方式来控制自己的健康即使你不能减掉体重并且保持住。

8:47Diets 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.

节食并不是非常值得信赖的节食五年之后大多数人体重会反弹其中百分之四十的人甚至比原来还要重如果你想到这些节食的一般结果是在长期过程中更有可能增重而不是减重。

9:07If 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 thingand 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.

如果我已经让你相信节食会带来一些麻烦下一个问题便是，你会做些什么？我的答案是，简单说，就是留心我并不是说你需要学着调整或开始练习瑜伽我指的是在吃上面多加注意学会了解身体发出的信号这样可以让你在饿的时候吃在饱的时候停下来因为大量的增重归结为在并不饿的时候吃东西你该怎么做？允许自己尽可能的吃然后找出吃多少才能让你感觉舒服你需要一心一意坐下来吃一日三餐当你开始吃和吃完之后想想你的身体感觉如何让你的饥饿感决定你应该什么时候停止我花了差不多一年才学到这些但是我做这些确实很值得在食物面前，比起之前我变得更加释然我经常不去想它我会忘记家里有巧克力这就像外星人控制了我的大脑一样生活变得完全不同了我需要说的是这个方法可能不会让你减重如果你不是经常在你不饿的时候吃东西但是医生们并不知道可以让很多人都能显著减重的方法这就是为什么现在很多人专注于防止体重增加而不是让体重减轻我们需要面对现实如果节食有效的话，所有人现在都已经瘦下来了（笑声）为什么我们一直做同样的事情并且期待不同的结果？节食似乎是无害的但是它确实会带来很多附带的危害在最坏的情况下，它会危及生命体重的困扰会导致饮食混乱特别是在小孩子当中出现在美国，80%的10岁女孩说她们在节食我们的女儿们学会的是用错误的标尺来衡量她们的价值即使结果很好节食还是既浪费时间又浪费精力它消耗一种意志，而你可以将其用在帮助你的孩子完成作业或者完成一项重要的计划因为意志十分有限任何依赖坚持不懈的行动计划当你把注意力分散到其他方面的时候当你把注意力分散到其他方面的时候最终一定会以失败告终。

11:54Let 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.

我来让大家做一下最后的思考假如我们告诉所有那些节食的女孩子们当她们觉得饿时吃东西是可以的将会怎么样？假如我们教她们控制她们的食欲而不是惧怕它？我想她们大多数会变得更加快乐健康当她们成年之后她们中很多人可能会变瘦我真希望在我13岁那年有人告诉我这些。