好英语网糖真的有害健康吗？
It’s hard to imagine now, but there was a time when humans only had access to sugar for a few months a year when fruit was in season. Some 80,000 years ago, hunter-gatherers ate fruit sporadically and infrequently, since they were competing with birds.
虽然现在难以想象，但曾几何时，人类只能在水果成熟的几个月里吃到糖。大约8万年前，从事狩猎和采集活动的人类只能偶尔吃到少量水果，还要跟鸟抢着吃。
Now, our sugar hits come all year round, often with less nutritional value and far more easily – by simply opening a soft drink or cereal box. It doesn’t take an expert to see that our modern sugar intake is less healthy than it was in our foraging days. Today, sugar has become public health enemy number one: governments are taxing it, schools and hospitals are removing it from vending machines and experts are advising that we remove it completely from our diets.
现在，我们全年都能吃到大量的糖，糖的营养意义降低，吃到糖的难度也大大下降，开瓶汽水或者开盒麦片即可。不是专家也知道，现代人糖的摄入量不及以前四处找糖的时期健康。如今，糖已经成了公共健康的头号敌人：政府对糖征税，学校和医院不在自动售货机里卖糖，专家建议在饮食中完全不摄入糖。
“糖”一词涵盖了多种甜味剂，也包括水果中的天然果糖
But so far, scientists have had a difficult time proving how it affects our health, independent of a diet too high in calories.
但到目前为止，科学家还难以证明糖如何独立于高热量饮食之外影响着我们的健康。
Meanwhile, there is also a growing argument that demonising a single food is dangerous – and causes confusion that risks us cutting out vital foods.
也有越来越多的声音认为，将某种食物妖魔化十分危险，并且会造成困惑，可能导致我们停止食用至关重要的食物。
Sugar, otherwise known as ‘added sugar’, includes table sugar, sweeteners, honey and fruit juices, and is extracted, refined and added to food and drink to improve taste.
糖，又名“添加糖”，包括蔗糖、甜味剂、蜂蜜和果汁，经提取和精炼后加入食品和饮料中，以改善口味。
But both complex and simple carbohydrates are made up of sugar molecules, which are broken down by digestion into glucose and used by every cell in the body to generate energy and fuel the brain. Complex carbohydrates include wholegrains and vegetables. Simple carbohydrates are more easily digested and quickly release sugar into the bloodstream. They include sugars found naturally in the foods we eat, such as fructose, lactose, sucrose and glucose and others, like high fructose corn syrup, which are manmade.
但糖其实是一个广义概念，包括了成分或复杂或简单的碳水化合物。碳水化合物经由人体消化分解成葡萄糖，帮助人体细胞产生能量，并维持大脑运转。复杂的碳水化合物包括全谷物和蔬菜。简单的碳水化合物更容易消化，会迅速将糖释放到血液中，包括天然存在于食物中的糖，譬如果糖、乳糖、蔗糖和葡萄糖，以及其他人造糖，比如高果糖玉米糖浆。
Before the 16th Century only the rich could afford sugar. But it became more available with colonial trade.
在16世纪之前，只有富人才吃得起糖。但随着殖民贸易，糖变得越来越普遍。
Then, in the 1960s, the development of large-scale conversion of glucose into fructose led to the creation of high fructose corn syrup, a concentrate of glucose and fructose.
上世纪60年代，葡萄糖开始能够被大规模地转化为果糖，促生了高果糖玉米糖浆，一种葡萄糖和果糖的浓缩物。
This potent combination, above any other single type of sugar, is the one many public health advocates consider the most lethal – and it is the one that many people think of when they think of ‘sugar’.
很多倡导公共健康的人士认为，这种味道浓烈的混合物比其他任何单一糖类都危险。而很多人想到“糖”时，想到的就是高果糖玉米糖浆。
Sugar rush
高糖热潮
Consumption of high fructose corn syrup in the US increased tenfold between 1970 and 1990, more than any other food group. Researchers have pointed out that this mirrors the increase in obesity across the country.
从1970年到1990年，美国的高果糖玉米糖浆消耗量增加了10倍，增幅比其他任何食品都高。研究人员指出，这也反映在了全美肥胖现象越来越多。这可能是因为高果糖玉米糖浆不同于其他食物，它不会增加瘦素。瘦素是一种激素，有助于我们产生饱腹感。
Meanwhile, sugary drinks, which usually use high fructose corn syrup, have been central to research examining the effects of sugar on our health. One meta-analysis of 88 studies found a link between sugary drinks consumption and body weight. In other words, people don’t fully compensate for getting energy from soft drinks by consuming less of other foods – possibly because these drinks increase hunger or decrease satiety.
含糖饮料一般会使用高果糖玉米糖浆，在研究糖对人体健康的影响中一直是个重要对象。对88项研究进行的一项荟萃分析发现，饮用含糖饮料与体重高低相关。换句话说，人们不会因为喝了汽水获得了热量就少吃其他食物，可能因为这些饮料增加了饥饿感，或减少了饱腹感。
But the researchers concluded that while the intake of soft drinks and added sugars has increased alongside obesity in the US, the data only represents broad correlations.
但研究人员认为，虽然美国汽水和添加糖的摄入量连同肥胖现象一起增加了，但数据只表示两者大致相关。
And not everyone agrees that high fructose corn syrup is the driving factor in the obesity crisis. Some experts point out that consumption of the sugar has been declining for the past 10 years in countries including the US, even while obesity levels have been rising. There also are epidemics of obesity and diabetes in areas where there is little or no high fructose corn syrup available, such as Australia and Europe.
不是所有人都认同高果糖玉米糖浆造成了肥胖危机。一些专家指出，过去10年中，包括美国在内的一些国家，糖消耗量持续下降，但肥胖水平却一直上升。在澳大利亚和欧洲等几乎或完全不使用高果糖玉米糖浆的地区，也出现了大量肥胖症和糖尿病。
High fructose corn syrup isn’t the only kind of sugar seen as problematic. Added sugar, particularly fructose, is blamed for a variety of problems.
高果糖玉米糖浆不是唯一被认为会引起健康问题的糖。添加糖，尤其是果糖，被认为是各种问题的罪魁祸首。
For one, it’s said to cause heart disease. When liver cells break down fructose, one of the end products is triglyceride – a form of fat – which can build up in liver cells over time. When it is released into the bloodstream, it can contribute to the growth of fat-filled plaque inside artery walls.
比如认为果糖会引起心脏病。肝细胞在分解果糖时，有个最终产物是甘油三酯。甘油三酯是一种脂肪，会不断在肝细胞中累积。当甘油三酯进入血液，可能会导致动脉血管内部形成富含脂肪的斑块。
One 15-year study seemed to back this up: it found that people who consumed 25% or more of their daily calories as added sugar were more than twice as likely to die from heart disease than those who consumed less than 10%. Type 2 diabetes also is attributed to added sugar intake. Two large studies in the 1990s found that women who consumed more than one soft drink or fruit juice per day were twice as likely to develop diabetes as those who rarely did so.
一项为期15年的研究似乎证实了这一点：研究发现，每天摄入的热量中，添加糖的比例占25%或以上的人，死于心脏病的几率是占比低于10%的人的两倍多。食用添加糖还会引发2型糖尿病。上世纪90年代的两项大型研究发现，相比于几乎不喝汽水及果汁的女性，每天饮用超过一杯的女性患糖尿病的几率会高出一倍。
Sweet nothings?
糖是无辜的？
But again, it’s unclear if that means sugar actually causes heart disease or diabetes. Luc Tappy, professor of physiology at the University of Lausanne, is one of many scientists who argue that the main cause of diabetes, obesity and high blood pressure is excess calorie intake, and that sugar is simply one component of this.
但目前还不清楚糖是否真的导致了心脏病或糖尿病。包括瑞士洛桑大学生理学教授塔皮（Luc Tappy）在内的很多科学家认为，造成糖尿病、肥胖症和高血压的主要原因是热量摄入过量，糖只是热量的一种。
“More energy intake than energy expenditure will, in the long term, lead to fat deposition, insulin resistance and a fatty liver, whatever the diet composition,” he says. “In people with a high energy output and a matched energy intake, even a high fructose/sugar diet will be well tolerated.”
“长远来看，无论何种饮食结构，只要能量摄入多于消耗，就会导致脂肪堆积、胰岛素抵抗和脂肪肝，”他说，“而能量消耗和摄入相匹配的人，即使是高果糖/高糖饮食也完全没问题。”
Tappy points out that athletes, for example, often have higher sugar consumption but lower rates of cardiovascular disease: high fructose intake can be metabolised during exercise to increase performance.
塔皮指出，比如运动员的糖消耗量往往更高，但患心血管疾病的几率却更低，为了提高成绩他们会进行运动，能将摄入的大量果糖代谢掉。
Overall, evidence that added sugar directly causes type 2 diabetes, heart disease, obesity or cancer is thin. Yes, higher intakes are associated with these conditions. But clinical trials have yet to establish that it causes them.
总的来说，添加糖直接导致2型糖尿病、心脏病、肥胖症或癌症的证据不足。添加糖摄入量较高确实与这些疾病有关，但临床试验还没有证实是糖导致了这些疾病。
Sugar also has been associated with addiction… but this finding, too, may not be what it seems. A review published in the British Journal of Sports Medicine in 2017 cited findings that mice can experience sugar withdrawal and argued that sugar produces similar effects to cocaine, such as craving. But the paper was widely accused of misinterpreting the evidence. One key criticism was that the animals were restricted to having sugar for two hours a day: if you allow them to have it whenever they want it, which reflects how we consume it, they don’t show addiction-like behaviours.
常常还说糖会上瘾，但这可能也并非如此。《英国运动医学杂志》2017年发表的一篇文章提到，多项研究发现老鼠可能会出现糖分戒断症状，并认为糖会产生与可卡因类似的作用，比如渴求感。但这篇文章饱受诟病，被认为误解了相关证据。一种批评认为，动物吃糖的时间被限制在一天两小时，如果允许它们像人类一样想吃就吃，就不会出现类似上瘾的行为。
Still, studies have demonstrated other ways in which sugar affects our brains. Matthew Pase, research fellow at Swinburne’s Centre for Human Psychopharmacology in Australia, examined the association between self-reported sugary beverage consumption and markers of brain health determined by MRI scans. Those who drank soft drinks and fruit juices more frequently displayed smaller average brain volumes and poorer memory function. Consuming two sugary drinks per day aged the brain two years compared to those who didn’t drink any at all. But Pase explains that since he only measured fruit juice intake, he can’t be sure that sugar alone is what affects brain health.
但还有很多研究表明，糖会以其他方式影响我们的大脑。澳大利亚斯威本大学人类精神药理学中心的研究员帕塞（Matthew Pase）请被试对象报告他们喝了多少含糖饮料，并用核磁共振扫描他们大脑的健康状况，研究了摄入量与大脑健康的关系。喝汽水和果汁频率更高的人，平均脑容量更小，记忆力更差。每天喝两杯含糖饮料的人大脑比完全不喝的人老两岁。但帕塞说，他只测算了果汁的摄入量，因此无法确定影响大脑健康的是不是只有糖。
“People who drink more fruit juice or soft drinks may share other dietary or lifestyle habits that relate to brain health. For example, they may also exercise less,” Pase says.
帕塞说：“喝果汁或汽水较多的人可能都有其他影响大脑健康的饮食或生活习惯。比如，可能锻炼得也少。”
One recent study found that sugar may even help improve memory and performance in older adults. Researchers gave participants a drink containing a small amount of glucose and asked them to perform various memory tasks. Other participants were given a drink containing artificial sweetener as a control. They measured the participants' levels of engagement, their memory score, and their own perception of how much effort they’d applied.
最近的一项研究发现，糖甚至可能有助于改善老年人的记忆力和表现。研究人员给参试者一杯含少量葡萄糖的饮料，并请他们完成各种各样的记忆任务，另外一些参试者作为参照喝的是含人工甜味剂的饮料。研究人员检测了参试者的投入程度、记忆分数和他们自认为付出了多少努力。
The results suggested that consuming sugar can make older people more motivated to perform difficult tasks at full capacity – without them feeling as if they tried harder. Increased blood sugar levels also made them feel happier during the task.
结果表明，摄入糖分能够让老年人更积极地去全力完成困难的任务，同时不觉得自己付出了更多努力。血糖水平升高还会让他们在完成任务的过程中更加快乐。
Younger adults showed increased energy after consuming the glucose drink, but it didn’t affect their mood or memory.
年轻人喝了葡萄糖饮料后会增加能量，但不会影响他们的情绪或记忆力。
Teaspoon of sugar
稍来点糖
While current guidelines advise that added sugars shouldn't make up more than 5% of our daily calorie intake, dietitian Renee McGregor says it’s important to understand that a healthy, balanced diet is different for everyone.
尽管目前的指南建议添加糖不应超过每日热量摄取的5%，但营养学家麦格雷戈（Renee McGregor）说，重要的是要明白健康和均衡的饮食因人而异。
“I work with athletes who need to take on more sugar when doing a hard session because it’s easily digestible. But they worry they’re going over the guidelines,” she says.
“我指导的运动员在进行艰苦的训练时必须增加糖的摄入量，因为糖容易消化。但他们担心会超过指南规定的量。”她说。
For most of us non-athletes, it’s true that added sugar isn’t crucial for a healthy diet. But some experts warn we shouldn’t single it out as toxic.
对我们大部分普通人来说，添加糖确实不是健康饮食的关键。但一些专家警告说，我们不该认为只有添加糖有害健康。
McGregor, whose clients include those with orthorexia, a fixation with eating healthily, says that it isn’t healthy to label foods as ‘good’ or ‘bad’. And turning sugar into a taboo may only make it more tempting. “As soon as you say you can’t have something, you want it,” she says. “That’s why I never say anything is off-limits. I’ll say a food has no nutritional value. But sometimes foods have other values.”
麦格雷戈的客户包括健康食品症患者，会对健康饮食过度迷恋。她说，给食物贴上“好”或“坏”的标签是不合理的。禁止吃糖只会增加它的吸引力。“一旦你说不能吃什么，你就越想吃什么，”她说，“所以我从不说禁止吃某种食物，我会说它没有营养价值。但有时，食物也有其他价值。”
Associate professor at James Madison University Alan Levinovitz studies the relationship between religion and science. He says there’s a simple reason we look at sugar as evil: throughout history, we’ve demonised the things we find hardest to resist (think of sexual pleasure in the Victorian times).
美国詹姆斯麦迪逊大学副教授列文诺维茨（Alan Levinovitz）研究的是宗教与科学的关系。他说，我们认为糖邪恶的原因很简单：纵观历史，我们总是把最难抗拒的东西妖魔化（譬如维多利亚时代将性快感妖魔化）。
Today, we do this with sugar to gain control over cravings.
如今，我们对糖这么做是为了控制渴望。
“Sugar is intensely pleasurable, so we have to see it as a cardinal sin. When we see things in simple good and evil binaries, it becomes unthinkable that this evil thing can exist in moderation. This is happening with sugar,” he says.
“糖能给人带来极大的愉悦，所以我们必须把它看成是头等大罪。当我们用简单的好坏二元论来看待事物时，想到邪恶的东西居然可以适量存在就会感到不可思议。对糖的看法就是这样。”他说。
He argues that that seeing food in such extremes can make us anxious about what we’re eating – and add a moral judgment onto something as necessary, and as everyday, as deciding what to eat.
他认为，用如此极端的态度对待食物可能会让我们担心吃的东西，并在每天决定吃什么时进行一场道德判断，思考是否有必要吃。
Taking sugar out of our diets can even be counterproductive: it can mean replacing it with something potentially more calorific, such as if you substitute a fat for a sugar in a recipe.
在饮食中去掉糖甚至可能适得其反：可能意味着用热量更高的东西取代糖，比如做菜时用脂肪代替糖。
And amid the rising debate around sugar, we risk confusing those foods and drinks with added sugar that lack other essential nutrients, like soft drinks, with healthy foods that have sugars, like fruit.
有关糖的争论越来越激烈，我们可能会将类似汽水这种含添加糖但缺少其他必需营养物质的食品和饮料，与水果等含糖的健康食品相混淆。
One person who struggled with this distinction is 28-year-old Tina Grundin of Sweden, who says she used to think all sugars were unhealthy. She pursued a high-protein, high-fat vegan diet, which she says led to an undiagnosed eating disorder.
28岁的瑞典人格伦丁（Tina Grundin）就一度难以区分这两者，她说过去以为所有的糖都不健康。她遵循高蛋白、高脂肪的纯素饮食，导致患上了一种尚未确诊的饮食失调。
“When I started throwing up after eating, I knew I couldn’t go on much longer. I’d grown up fearing sugar in all forms,” she says. “Then I realised there was a difference between added sugar and sugar as a carbohydrate and I adopted a high-fructose, high-starch diet with natural sugars found in fruit, vegetables, starches and legumes.
“当我开始在饭后呕吐时，我知道不能再这样了。我从小到大一直害怕各种形式的糖，”她说，“后来我意识到，添加糖和碳水化合物中的糖是有区别的，于是我开始进行高果糖、高淀粉的饮食，接受水果、蔬菜、淀粉和豆类中的天然糖分。”
“From the first day, it was like the fog lifted and I could see clearly. I finally gave my cells fuel, found in glucose, from carbohydrates, from sugars.”
“从第一天开始，就像大雾散去，我终于看清了。我终于让体内的细胞得到了能量，这些能量来自葡萄糖、碳水化合物和糖类。”
While there’s disagreement around how different types of sugars affect our health, the irony is we might be better off thinking about it less.
不同糖类对人体健康的影响还没有定论，但可能考虑得越少越好。
“We’ve really overcomplicated nutrition because, fundamentally, what everyone is searching for is a need to feel complete, to feel perfect and successful,” says McGregor. “But that doesn’t exist.”
麦格雷戈说：“我们真的把营养过分复杂化了，从根本上说，所有人都在寻找圆满、完美和成功的感觉，但这其实并不存在。”