Nuts Are a Nutritional Powerhouse

多食坚果并不会使人发胖

Sadly, for more than half my life, I had avoided some of nature’s most perfect and healthful foods: nuts and peanuts. I had been mistakenly told as a teenager that nuts were fattening and constipating, effects I certainly wanted to avoid。

真可惜，在我的有生之年里，有一半以上的时间我都刻意地不去吃大自然中最完美也是最健康的食物：坚果和花生。这都是因为在我十几岁的时候，有人误导我，说吃坚果会让我发胖，还会导致便秘，结果——我当然会想要避免食用它们了。

But based on what I have learned to the contrary from recent studies, I now enjoy them daily as nuts or nut butters in my breakfasts, salads, sandwiches and snacks. A baggie of lightly salted peanuts accompanies me on excursions everywhere; I even keep a jar of peanuts in my car。

但是，据我了解，最近的研究结果与之恰恰相反。于是，我现在每天的早餐、沙拉、三明治和零食中，都有坚果或坚果酱。无论我去哪里远足，都会随身带一袋淡盐花生；我甚至在我的车里放了一罐花生。

A series of large studies, including the Nurses’ Health Study of 76,464 women and the Health Professionals Follow-Up Study of 42,498 men, found that the more nuts people consumed, the less likely they were to die at any given age, especially of cancer or heart disease. And a clinical trial conducted in Spain showed that death rates were lower among those consuming a Mediterranean diet supplemented with extra nuts。

包括护士健康研究(Nurses Health Study，涉及76464名女性)和医药卫生从业人员随访研究(Health Professionals Follow-up Study，涉及42498名女性)在内的一系列大型研究发现，人们食用的坚果越多，他们在任何给定年龄死亡，尤其是死于癌症或心脏病的可能性就越小。一 项在西班牙进行的临床试验表明，坚持地中海饮食并额外补充坚果的人死亡率较低。

However, these studies were conducted almost entirely among relatively well-to-do, well educated, white individuals, and despite the researchers’ care in controlling for other factors that could have influenced the results, there remained the possibility that characteristics of the participants other than nut consumption could account for their reduced death rates。

然而，这些研究几乎全是在相对富裕、受过良好教育的白人中进行的，尽管研究人员对可能影响结果的其他因素小心地进行了控制和校正，但仍有可能是参与者的特征而非食用坚果降低了他们的死亡率。

Now, strong links between nuts and peanuts and better health have also been found in a major study of people from lower socioeconomic backgrounds and varied ethnic groups — blacks, whites and Asians — many of whom had serious risk factors for premature death, like smoking, obesity, high blood pressure and diabetes。

现在，一项大型研究同样发现，坚果和花生与较好的健康之间存在密切关联，研究纳入了社会经济背景较差的黑人、白人和亚洲人等不同族群，其中许多人都存在过早死亡的高危因素，如抽烟、肥胖、高血压和糖尿病等。

The results were published in March in JAMA Internal Medicine by researchers at Vanderbilt University School of Medicine. Their study, conducted among more than 200,000 men and women in the Southern United States and Shanghai, found that the more nuts people consumed, the lower their death rates from all causes and especially from heart disease and stroke。

范德堡大学医学院(Vanderbilt University School of Medicine)的研究人员将该研究结果发表在今年3月的《美国医学会期刊：内科学》杂志(JAMA Internal Medicine)上。研究涉及美国南部和上海的超过20万名男性和女性，结果发现，人们吃的坚果越多，他们的全因死亡率，尤其是心脏病和中风死亡率就越 低。

And while it is true that more people today are allergic to nuts, and to peanuts in particular, than ever before, two recent studies have pointed to ways that may prevent children from developing a nut allergy. The first study, published last year in JAMA Pediatrics, found that women who consumed the most nuts or peanuts during their pregnancies were least likely to have children with this allergy. The reduction in risk was highest among children whose mothers ate nuts five or more times a month。

虽然今天对坚果，特别是花生过敏的人确实比以往任何时候都多，但最近有两项研究提出了可以防止儿童发生坚果过敏的方法。第一项研究发表在去年的《美 国医学会期刊：儿科学》(JAMA Pediatrics)上，它发现在妊娠期食用坚果或花生最多的孕妇日后生下的孩子最不可能发生这类过敏。母亲每个月至少吃五次坚果，孩子的风险降低最 多。

The second study, published in February in The New England Journal of Medicine, found that introducing peanuts into the diets of infants 4 to 11 months old who were considered at high risk of developing a peanut allergy actually greatly reduced their risk of being allergic at age 5. The researchers, from King’s College London, suggested that the common practice of withholding peanuts from babies may in fact account for the recent rise in peanut allergies。

第二项研究发表在今年2月的《新英格兰医学杂志》(The New England Journal of Medicine)上，该研究发现，对于被认为日后花生过敏风险较高的婴儿，在其4到11个月大时向其饮食中引入花生实际上大大降低了他们在5岁时出现过 敏的风险。承担研究的英国伦敦国王学院(King’s College London)的研究人员提出，从婴儿饮食中去除花生的常见做法可能其实反而是造成近期花生过敏不断增加的元凶。

Guidelines issued in 2000 by the American Academy of Pediatrics recommended withholding peanuts from children at risk of developing allergies until they were 3. The academy has since revised its position, suggesting that evidence that avoiding specific foods beyond 4 to 6 months of age prevented food allergies was lacking. Now a further revision by the academy may be in order, though to prevent choking, babies should not be given whole nuts — only ground nuts or nut butters。

美国儿科学会(American Academy of Pediatrics)在2000年发布的指南建议从存在过敏风险的儿童的饮食中排除花生，直到他们年满3岁为止。该学会现已修正了自己的立场，指出 “4-6个月以上的儿童不食用特定食物就可以防止食物过敏”的说法缺乏证据支持。如今，按照计划，该学会将对指南做出下一轮修订(美国儿科学会的指南通常 每5年修订一次——译注)。不过，需要注意的是，为了避免婴儿被噎住而窒息，不应该让婴儿直接吃整个儿的坚果——他们只能吃干果碎和坚果酱。

Before returning to the relationship between nuts and better health, I want to reassure weight-conscious readers that, when consumed in reasonable quantities, nuts are not fattening and can even help people lose weight and maintain the loss。

在说回坚果与更好的健康之间的关系之前，我想请在意自己体重的读者放心，只要摄入量合理，坚果就不会让人发胖，甚至，它们可以帮助人们减肥并保持身材。

Yes, relatively speaking, nuts are high in fat, and fat contains more calories per gram (nine) than protein or sugar (four calories)， even more than alcohol (seven calories). But a review of studies of large populations here and abroad by Richard D. Mattes of Purdue University and co-authors most often found that adults who eat nuts weigh less than nut avoiders. And children who ate peanuts usually had a lower body mass index than those who did not。

的确，相对而言，坚果是种高脂肪食品，而每克脂肪中蕴含的热量(九卡路里)比蛋白质或糖(四卡路里)都高，甚至还超过了酒精(七卡路里)。但是，美 国普渡大学(Purdue University)的理查德·D·马特斯(Richard D. Mattes)和共同作者综述了调查美国和国外的大群体的研究，发现最常见的情况是，吃坚果的成年人体重小于不吃坚果者。而且，经常食用花生的儿童身体质 量指数通常也低于不吃花生的儿童。

Clinical trials found that adding lots of nuts to one’s diet had a limited effect on body weight. But more important, participants in studies that included nuts in a weight-loss regimen lost more weight and ended up with a smaller waist and less body fat than participants who did not eat nuts。

临床试验发现，在一个人的饮食中添加大量坚果对体重的影响有限。但更重要的是，与不吃坚果的研究参与者相比，在减肥疗程中纳入坚果的参与者体重减轻更多，最终腰围更细，体脂肪也更少。

One explanation for the weight control benefit of nuts is the satiation provided by their high fat and protein content, which can reduce snacking on sweets and other carbohydrates. Another is that all the calories in nuts, especially whole nuts, may not be absorbed because they resist breakdown by body enzymes。

对于坚果的体重控制效益，一种解释是它们的高脂肪和高蛋白质含量提供了饱食感，让人少吃甜食和其他碳水化合物等零食。另一种解释是，人无法完全吸收坚果，尤其是整个儿的坚果中的所有热量，因为它们不太容易被体内的酶分解。

Finally, in a 2013 study in The British Journal of Nutrition, Dr. Mattes and colleagues reported that consuming peanut butter or peanuts for breakfast helps to control hunger, stabilizing blood sugar and reducing the desire to eat for up to 8 to 12 hours. (My favorite breakfast: half a banana, sliced, with each slice topped by a half-teaspoon of crunchy peanut butter。)

最后，马特斯博士及其同事在2013年发表在《英国营养学杂志》(The British Journal of Nutrition)上的一项研究中报告，早餐食用花生酱或花生有助于控制饥饿感，稳定血糖，并可降低食欲达8-12小时。(我最喜欢的早餐是：香蕉半 根，切片，每片淋上半茶匙脆脆的花生酱。)

As for their cardiovascular benefits, nuts are rich sources of monounsaturated and polyunsaturated fats, which prompted a health claim by the Food and Drug Administration that “Scientific evidence suggests but does not prove that eating 1.5 ounces per day of most nuts as part of a diet low in saturated fat and cholesterol may reduce the risk of heart disease。” Two exceptions are macadamia nuts and cashews, which have too much saturated fat to qualify for this claim。

就其心血管效益而言，坚果富含单不饱和与多不饱和脂肪，因此美国食品和药品监督管理局(Food and Drug Administration)发布了健康声明：“科学证据显示(不是证实！)，作为低饱和脂肪、低胆固醇饮食的一部分，每天食用大多数坚果1.5盎司 (约合42.5克)可降低患心脏病的风险。”不过有两个例外：澳洲坚果和腰果，它们含有过多的饱和脂肪，不符合声明中的要求。

Nuts are also rich sources of dietary fiber, and almonds, Brazil nuts, peanuts and walnuts may actually help prevent constipation, countering my long-held concerns about their effects on digestion. Other beneficial substances in nuts include vitamins, antioxidants and other phytochemicals. All of which adds up to nuts as a nutritional powerhouse。

坚果中还含有丰富的膳食纤维，实际上，杏仁、巴西果、花生和核桃可能有助于防止便秘，这抵消了我长期以来对其可能影响消化功能的担忧。坚果蕴含的其它有益物质还包括：维生素、抗氧化剂和其它植物化学成分。所有这些加起来，使坚果成为了一座营养丰富的能量宝库。