怎样吃才能更长寿？

多年来，关于健康饮食，人们看到了许多相互矛盾的建议。

First, fat was the bad guy. Then it was considered ideal to avoid sugar and go low-carb.

首先，他们说胖是一件坏事，然后出现了只吃肉类、蔬菜而不吃碳化水化合的减肥法。

Lately, dieters trying the trendy ketogenic diet have discovered that if they replace carbs with fat, they can trick their bodies into a natural starvation mode and lose weight, while still enjoying bacon and slurping heavy cream.

前不久的减肥时尚是上世纪本来用于治疗儿童癫痫的生酮饮食：如用脂肪替代碳水化合物，可以欺骗我们的身体进入自然饥饿模式并迫使身体分解存储的脂肪以维持生命;同时一点不妨碍我们继续享用美味的培根和醇厚的奶油。

But a new, long-term study published Thursday in The Lancet suggests there may be a winning formula for the amount of carbohydrates to eat every day. It relies on some very unsexy, old advice: everything in moderation.

但上周四在《柳叶刀》上发表的一项新的长期研究表明，存在一个最佳公式，每天摄入一定的碳水化合物可以使健康收益最大化。它依赖于一句老套的箴言：过犹不及。

Lead researcher Sara Seidelmann, a cardiologist and nutrition researcher at Brigham and Women's Hospital in Boston, told Business Insider that her results suggested a diet "rich in plant based whole foods such as vegetables, whole grains, legumes, and nuts is associated with healthy ageing."

首席研究员，波士顿布莱根妇女医院的心脏病专家兼营养学研究员Sara Seidelmann指出，她的研究结果表明“全植物性的饮食习惯，如蔬菜、全谷物、豆类和坚果，与更长的预期寿命有关”。

That usually means about half of the calories you eat in a day should come from carbohydrates.

而这通常意味着你一天吃进去的卡路里大约有一半应来自碳水化合物。

A Goldilocks rule for carbs

碳水化合物的金发姑娘规则

For the study, Seidelmann looked at the diets of more than 15,400 adults in the US and another 432,000 people in more than 20 countries around the world. She and her team of researchers analysed that information in relation to how long the study participants lived.

在这项研究中，Seidelmann分析了美国超过15400名成年人以及全球20多个国家的432000名成年人的饮食习惯。她的研究团队采集了参与者在健康方面的信息。

They found that people who ate a moderate amount of carbohydrates – around half of their daily calories – tended to live the longest.

他们发现，摄入适量碳水化合物——大约提供每日总卡路里的一半——的人往往生存时间最长。

Conversely, people who derived more than 70 percent of their energy from carbs or got less than 40 percent of their daily calories from carbohydrates were more likely to die than people who ate something in between.

相反，那些从碳水化合物中获取70%以上或者不足40%热量的人，预期寿命低于中间的人群。

It's a kind of Goldilocks finding: we should eat not too many carbs, not too few, but just the right amount.

这是中庸的胜利：我们应该吃不太多或太少的碳水化合物，恰到好处才是最好。

On one end of the spectrum are people who suffer health consequences from eating too many carbs, like in some lower-income countries where people tend to rely on white rice for sustenance without much else on their plate.

一方面，在一些低收入国家，人们倾向于单纯依赖大米和小麦这样的主食来维持生计。

On the other end are people who consume not enough carbs. Surprisingly, the group at highest risk of death in the US study were those who didn't eat carbs, since those people tended to replace carb-heavy foods with animal fats and proteins: "beef, pork, lamb, chicken, and cheese," as Seidelmann put it.

另一方面，令人惊讶的是，研究中发现，死亡风险最高的人群是那些不吃碳水化合物的人，因为他们倾向于用动物脂肪和蛋白质来替代碳水化合物：“牛肉，猪肉，羊肉，鸡肉和奶酪。”

"Clearly, filling your plate with those things increased mortality," she said.

“很明显，用这些东西填满你的盘子会提高你的死亡风险。”Seidelmann说。

In fact, the researchers concluded that a 50-year-old who eats within the 50-55 percent carbs margin could expect to live for another 33.1 years, while someone the same age who gets just 30 percent of their calories from carbs would be expected to live roughly 29.1 more years.

事实上，研究人员得出的结论是，50岁左右的人，如果日常饮食中碳水化合物提供的热量占全部食物的50-55%，那他之后的预期生命长度是33.1年;而如果他只从碳水化合物中获取30%的卡路里，那预期长度是29.1年。

The important part is getting as many whole, healthful foods onto your plate as possible

尽可能多吃健康食品

There is a way to do a low-carb diet and age well: people who ate small amounts of carbohydrates but more plant-based proteins like veggies, seeds, and nuts were found to be less likely to die and tended to live to a ripe old age.

因为存在碳水化合物的最佳比例，所以要想保持低碳水化合物的饮食，又希望长寿，那最好的方法就是降低每日饮食中总的卡路里——食用少量碳水化合物和更多的植物性蛋白质如蔬菜、种子和坚果，这样的人往往更加长寿。

This might be because eating large amounts of animal fat and protein but few fresh plant-based foods can increase inflammation in the body.

这可能是因为大量食用动物脂肪和蛋白质，而植物性食物摄入不足可以增加体内的炎症。

She agrees there's a short-term link between low-carb diets and weight loss, but cautions that diets like keto and Atkins might not be great long-term strategies.

她认可低碳水化合物饮食和减肥之间存在关联，但警告说，称像生酮饮食和阿特金斯减肥法这样的生活习惯是不具有可持续性的。

"There's absolutely nothing more important for our health than what we eat each and every day," she said. "I really would like individuals to realise the power that they have over their own health," she said.

对我们的健康来说，绝对没有什么比我们每天吃的更重要，”她说，“我真的希望每个人都能意识到他们对自己身体的影响力，只要改变和控制一些饮食习惯，就能收获更长的预期寿命。”