Myths of Weight Loss Are Plentiful, Researcher Says

　　关于减重，你应了解的谣言与真相

严格管理体重：你应了解的谣言与真相(双语)

　　If schools reinstated physical education classes, a lot of fat children would lose weight. And they might never have gotten fat in the first place if their mothers had just breast fed them when they were babies. But be warned: obese people should definitely steer clear of crash diets. And they can lose more than 50 pounds in five years simply by walking a mile a day。

　　如果学校能恢复体育课，许多胖小孩就能减肥了。如果他们的母亲能在他们的婴儿时期坚持母乳喂养，他们可能根本就胖不起来。但也要提醒的是：肥胖人群需要离垃圾食品远远的。他们只要每天步行一英里，五年就能减去50多磅。

　　Those are among the myths and unproven assumptions about obesity and weight loss that have been repeated so often and with such conviction that even scientists like David B. Allison, who directs the Nutrition Obesity Research Center at the University of Alabama at Birmingham, have fallen for some of them。

　　以上种种都是关于肥胖和减重的谣言或未经证实的假设；它们被反复提及，言之凿凿，甚至像戴维·B·艾里森(David B. Allison)这样的科学家也曾被其中的某些谣言迷惑，而他是伯明翰阿拉巴马大学(University of Alabama)营养肥胖研究中心的主管。

　　Now, he is trying to set the record straight. In an article published online today in The New England Journal of Medicine, he and his colleagues lay out seven myths and six unsubstantiated presumptions about obesity. They also list nine facts that, unfortunately, promise little in the way of quick fixes for the weight-obsessed. Example: “Trying to go on a diet or recommending that someone go on a diet does not generally work well in the long term。”

　　现在，他决定把这些问题搞搞清楚。在《新英格兰内科杂志》(The New England Journal of Medicine)在线版发表的一篇文章中，他和他的同事列出了关于肥胖的七条谣言和六项不确定的假设。他们也写明了九个事实，很不幸，减重没什么捷径。 比如：“尝试减肥食谱或推荐他人使用减肥食谱，通常没有什么长期效果。”

　　Obesity experts applauded this plain-spoken effort to dispel widespread confusion about obesity. The field, they say, has become something of a quagmire。

　　肥胖专家对这一直白的努力表示赞许，它驱散了广为流传的关于肥胖的困惑。他们说，这一领域曾像个越陷越深的沼泽。

　　“In my view,” said Dr. Jeffrey M. Friedman, a Rockefeller University obesity researcher, “there is more misinformation pretending to be fact in this field than in any other I can think of。”

　　“在我看来，”洛克菲勒大学(Rockefeller University)肥胖研究人员杰弗里·M·弗兰曼博士(Dr. Jeffrey M. Friedman)说，“相比我能想到的任何其他领域，肥胖领域存着更多似是而非的错误认知。”

　　Others agreed, saying it was about time someone tried to set the record straight。

　　其他人对此表示同意：是时候让人们认清真相了。

　　“I feel like cheering,” said Madelyn Fernstrom, founding director of the University of Pittsburgh Weight Management Center. When it comes to obesity beliefs, she said, “We are spinning out of control。”

　　“我感觉很受鼓舞，”美国匹兹堡大学(University of Pittsburgh)体重管理中心的创始主管梅德林·芬斯托姆(Madelyn Fernstrom)说。谈到肥胖信条，她说：“我们正在快速滑向失控。”

　　Steven N. Blair, an exercise and obesity researcher at the University of South Carolina, said his own students believe many of the myths. “I like to challenge my students. Can you show me the data? Too often that doesn’t come into it。”

　　在南卡罗来纳大学(University of South Carolina)，专门研究运动和肥胖的研究员史蒂文·N·布莱尔(Steven N. Blair)说，他的学生也相信其中很多谣言：“我喜欢挑战我的学生：你能找到证明你观点的数据吗？通常他们都拿不出来。”

　　Dr. Allison sought to establish what is known to be unequivocally true about obesity and weight loss。

　　艾里森博士试图建立肥胖和减重的已知明确关系。

　　His first thought was that, of course, weighing oneself daily helped control weight. He checked for the conclusive studies he knew must exist. They did not。

　　他起先想到的是，显然，每天称称自己有多重有助于控制体重。他于是开始搜寻他认为肯定已有明确结论的研究。但是，他没能搜到。

　　“My goodness, after 50-plus years of studying obesity in earnest and all the public wringing of hands, why don’t we know this answer?” Dr. Allison asked. “What’s striking is how easy it would be to check. Take a couple of thousand people and randomly assign them to weigh themselves every day or not。”

　　“天哪，50多年来，研究者在对肥胖症进行孜孜不倦的调查，公众对这个问题越来越重视，为什么我们还没找到答案？”艾里森博士追问：“令人震惊的是，这明明是很容易验证的。只需要找几千人，随机让他们每天称体重或者不称。”

　　Yet it has not been done。

　　但是还没人这么干过。

　　Instead, people often rely on weak studies that get repeated ad infinitum. It is commonly thought, for example, that people who eat breakfast are thinner. But that notion is based on studies of people who happened to eat breakfast. Researchers then asked if they were fatter or thinner than people who happened not to eat breakfast — and found an association between eating breakfast and being thinner. But such studies can be misleading because the two groups might be different in other ways that cause the breakfast eaters to be thinner. But no one has randomly assigned people to eat breakfast or not, which could cinch the argument。

　　相反，人们常常依赖一些证据单薄的研究。比如，人们普遍认为吃早餐的人更瘦，但是这一观点建立的基础，是对碰巧吃了早餐的人群进行研究。研究人员当 时询问他们比没吃早餐的人更胖还是更瘦——然后发现吃早餐和更瘦之间有关联。然而这种研究很可能是误导，因为这两组人群也许在生活的其他方面存在不同，导 致早餐组更瘦。但是，却没人随机把人们分成吃早餐组和不吃早餐组，而这样可以轻易平息争论。

　　So, Dr. Allison asks, why do yet another study of the association between thinness and breakfast? “Yet, I can tell you that in the last two weeks I saw an association study of breakfast eating in Islamabad and another in Inner Mongolia and another in a country I never heard of。”

　　所以，艾里森博士问，为什么还要再进行一个有关身材胖瘦和早餐之间联系的研究？“可是最近两周我就看到了三篇关于吃早餐和胖瘦因果关系的研究，一项研究在伊斯兰堡，另一项在内蒙古，还有一项的试验地点是一个我从来没听说过的国家。”

　　“Why are we doing these?” Dr. Allison asked. “All that time and effort is essentially wasted. The question is: ‘Is it a causal association?’” To get the answer, he added, “Do the clinical trial。”

　　“我们在干什么？”艾里森博士质疑，“所有的时间和精力都纯粹是种浪费。问题在于：‘它们有因果关联吗？’”他补充说，如果想得到确切的答案，“就做临床试验啊。”

　　He decided to do it himself, with university research funds. A few hundred people will be recruited and will be randomly assigned to one of three groups. Some will be told to eat breakfast every day, others to skip breakfast, and the third group will be given vague advice about whether to eat it or not。

　　他决定使用大学的研究经费自己来做试验。他召集了几百名对象，随机分为三组。一组每天都要吃早餐，一组不吃，第三组对于吃不吃早餐只给予模糊建议。

　　As he delved into the obesity literature, Dr. Allison began to ask himself why some myths and misconceptions are so commonplace. Often, he decided, the beliefs reflected a “reasonableness bias。” The advice sounds so reasonable it must be true. For example, the idea that people do the best on weight-loss programs if they set reasonable goals sounds so sensible。

　　研究了肥胖文献后，艾里森博士问自己，为什么某些谣言和误解如此常见。他认为这些信条往往反映了一种“合理的偏见”。这种建议听上去如此合理，所以人们想当然地认为它一定是对的。比如，有个建议说的是设立合理目标的人能把减重计划执行得最好，而这听上去十分合情合理。

　　“We all want to be reasonable,” Dr. Allison said. But, he said, when he examined weight-loss studies he found no consistent association between the ambitiousness of the goal and how much weight was lost and how long it had stayed off. This myth, though, illustrates the tricky ground weight-loss programs have to navigate when advising dieters. The problem is that on average people do not lose much – 10 percent of their weight is typical – but setting 10 percent as a goal is not necessarily the best strategy. A very few lose a lot more and some people may be inspired by the thought of a really life-changing weight loss。

　　“我们都希望达成合理的目标，”艾里森博士说。但当他探查减重研究时，他发现目标的野心程度与所减去的重量以及所花费的时间并无一致关系。然而，这 种谣言恰好说明，需要慎重探寻减重计划似是而非的科学依据，然后才能向节食者做出推荐。问题是，平均来说人们减的重量不多——通常是体重的10%——但把 10%设为目标不是最佳策略。只有少数人能多减一些，而有些人需要想象减重能令自己改头换面，以此来获得激励。

　　“If a patient says, ‘Do you think it is reasonable for me to lose 25 percent of my body weight,’ the honest answer is, ‘No. Not without surgery,’” Dr. Allison said. But, he said, “If a patient says, ‘My goal is to lose 25 percent of my body weight,’ I would say, ‘Go for it.’”

　　“如果病人问：‘你认为我要减去体重的25%合理吗？’诚实的回答是：‘不，不做手术的话达不到。’”艾里森博士说。但是，他又说：“如果病人说：‘我的目标是减去体重的25%。’我会说：‘努力吧。’”

　　Yet all this negativism bothers people, Dr. Allison conceded. When he talks about his findings to scientists, they often say: “O.K., you’ve convinced us. But what can we do? We’ve got to do something。” He replies that scientists have an ethical duty to make clear what is established and what is speculation. And while it is fine to recommend things like bike paths or weighing yourself daily, scientists must make sure they preface their advice with the caveat that these things seem sensible but have not been proven。

　　既然消极的言论会影响到人，艾里森博士做出了让步。当他与其他科学家讨论自己的发现时，他们常常会说：“好吧，你说服我们了。但我们能怎么办呢？总 得做点什么吧。”他回答说，科学家在伦理上有责任去阐明，什么是已证实的意见，什么只是推断。向人推荐骑行或每天称体重固然不错，但与此同时，科学家也应 该补充一句：这些建议听上去合情合理但并未经过证明。

　　Among the best established methods is weight-loss surgery, which, of course, is not right for most people. But surgeons have done careful studies to show that on average people lose substanial amounts of weight and their health improves, Dr. Allison said. For dieters, the best results occur with structured programs, like ones that supply complete meals or meal replacements。

　　在所有已经验证的减重方法中，最好的是去脂手术，但它对大多数人当然并不适用。艾里森博士说，外科医生已经进行了谨慎的研究，证明病人可以因此减去 大量体重并改善健康。对于节食者，结构性的调整效果最好，如食用全餐(含均衡的蔬菜水果、谷物和低脂蛋白质的一餐—编注)或代餐。

　　In the meantime, Dr. Allison said, it is incumbent upon scientists to change their ways. “We need to do rigorous studies,” he said. “We need to stop doing association studies after an association has clearly been demonstrated。”

　　艾里森博士说，与此同时科学家也有义务改变他们的行为方式。“我们需要做严谨的研究，”他说，“不能在做出一个已经明确证明了因果关系的研究后，再做一个因果关系研究。”

　　“I never said we have to wait for perfect knowledge,” Dr. Allison said. But, as John Lennon said, “Just give me some truth。”

　　“我从不认为我们只能坐等完美的知识出现，”艾里森博士说，但是，就像约翰·列侬(John Lennon)说过的那样，“给我一些真相。”

　　Here is an overview of the obesity myths looked at by the researchers and what is known to be true:

　　下面是一系列关于肥胖的谣言和已证实的事实，均已由研究人员证实真伪：

　　MYTHS

　　谣言

　　Small things make a big difference. Walking a mile a day can lead to a loss of more than 50 pounds in five years。

　　小动作带来大改变。每天步行一英里能让你在5年内减去50磅。

　　Set a realistic goal to lose a modest amount。

　　设立现实目标能减去适度体重。

　　People who are too ambitious will get frustrated and give up。

　　太有野心的人会因为不断受挫而最终放弃。

　　You have to be mentally ready to diet or you will never succeed。

　　你得在精神上做好节食准备，否则将永不成功。

　　Slow and steady is the way to lose. If you lose weight too fast you will lose less in the long run。

　　减重需要缓慢稳定。如果你减得太快，长远来看你减得更少。

　　Ideas not yet proven TRUE OR FALSE

　　尚未证明真假的观念

　　Diet and exercise habits in childhood set the stage for the rest of life。

　　儿童时期的饮食和运动习惯会影响终生。

　　Add lots of fruits and vegetables to your diet to lose weight or not gain as much。

　　饮食中加入大量水果和蔬菜能帮助减重或不增长太多。

　　Yo-yo diets lead to increased death rates。

　　反复减重会升高死亡率。

　　People who snack gain weight and get fat。

　　爱吃零食的人会增重变胖。

　　If you add bike paths, jogging trails, sidewalks and parks, people will not be as fat。

　　如果你骑行、慢跑、在街道或公园中步行，就不会那么胖。

　　FACTS — GOOD EVIDENCE TO SUPPORT

　　事实——有良好的证据支持

　　Heredity is important but is not destiny。

　　遗传很重要，但非决定性。

　　Exercise helps with weight maintenance。

　　运动有助于保持体重。

　　Weight loss is greater with programs that provide meals。

　　有饮食支持的减重计划更好。

　　Some prescription drugs help with weight loss and maintenance。

　　某些处方药有助于体重的减轻和保持。

　　Weight-loss surgery in appropriate patients can lead to long-term weight loss, less diabetes and a lower death rate。

　　相当一部分患者能通过减脂手术来获得长期的减重、较少发生糖尿病、死亡率较低。

　　本文选自《小火炉的博客》的新浪博客，请点击查看原文。