Hi, this is Your Health, Quickly, a Scientific American podcast series!

大家好，欢迎来到《科学美国人》播客系列节目《健康快讯》!

We bring you the latest vital health news: Discoveries that affect your body and your mind.

我们将为大家带来最新健康要闻：影响人们身心健康的发现。

And we break down the medical research to help you stay healthy.

我们将分析医学研究，帮助大家保持健康。

I’m Tanya Lewis. I’m Josh Fischman. We’re Scientific American’s senior health editors.

我是谭雅·刘易斯。我是乔希·费什曼。我们是《科学美国人》的高级健康编辑。

On today’s show, we’re talking about ultra-processed foods—what they are, whether they’re bad for you, and why it’s so hard to study their effects.

在今天的节目中，我们将讨论超加工食品是什么，它们是否对人体有害，以及为什么研究它们的影响如此困难。

I don’t know about you, Josh, but I’m a big fan of ice cream.

乔什，我不知道你怎么样，但我很喜欢吃冰淇淋。

I often eat cereal for breakfast, sometimes with a bit of fruit yogurt. And I enjoy a good gin cocktail.

我早餐经常吃麦片，有时加一点水果酸奶。我喜欢高品质的杜松子鸡尾酒。

What do you think these foods have in common?

你觉得这些食品有什么共同之处?

Wait a minute. You’re actually giving me a pop quiz?

等等，你真的要给我做突击测验吗?

Yes I am.

是的，我要给你做突击测验。

But there are so many different right answers here.

不过，有很多不同的正确答案。

All those foods have a lot of sugar. In one form or another. They’ve all been linked to poor health. And they all have fruit as an ingredient, even the gin.

所有这些食物都含有大量的糖。以这样或那样的形式。它们都被认为与身体不好有关。它们都以水果为配料，甚至杜松子酒也是如此。

Which one are you looking for?

哪个是你要找的答案?

The answer I was looking for was that they are all ultra-processed.

我想要的答案是，这些食品都经过超加工处理。

Oh. Yeah, of course. But what exactly is “ultra-processed food,” and how does it differ from “processed” food? Is it bad for you?

是的，当然。但究竟什么是“超加工食品”，它与“加工”食品有何不同？它对人体有害吗?

Here to answer some of these questions for us is our editorial intern, Lori Youmshajekian.

为我们回答其中一些问题的是我们的编辑实习生洛莉·尤姆沙基安。

She’s writing a news story about ultra-processed foods.

她正在写一篇关于超加工食品的新闻报道。

Lori, welcome to Your Health, Quickly!

洛莉，欢迎来到《健康快讯》节目!

Thanks for having me.

感谢你邀请我。

Hey there, Lori.

你好，洛莉。

So Lori, I’ve heard of processed foods before.

洛莉，我之前听说过加工食品。

I always thought of them as just any kind of packaged or prepared food, like chips or candy.

我一直觉得加工食品就是一种包装好的食物或现成的食物，比如薯片、糖果。

So what makes a food “ultra processed,” and how is that different from just “processed” food?

那么是什么让一种食物成为“超加工”食品呢? 它与“加工”食品又有什么不同呢?

So, the rule of thumb is that ultra-processed foods are the things that you can’t make in your own kitchen.

经验之谈是，超加工食品是你无法在自己的厨房里制作的东西。

And that’s because they’ve gone through some kind of industrial processing, where the ingredients have been changed in a way that you just wouldn’t be able to do with domestic equipment, or there are additives to preserve the food, make it crunchier, shinier, all those sorts of things.

这是因为它们经过了某种工业加工。原料在加工中发生了某种改变，这是你用家用设备无法做到的，里面的添加剂可以保存食物、使食物更松脆、更有光泽，诸如此类。

They’re typically designed to be ready to eat and really don’t resemble the raw ingredients they’re made from.

它们通常被设计成即食食品，与制作食物的原料完全不同。

What are some examples?

有什么例子吗?

You might recognize things like chips or sodas. But also granola bars or breakfast cereals, or even protein powders. So it’s a really diverse group of food.

你可能会辨别出薯片或苏打水之类的东西。不过，燕麦棒、早餐麦片，甚至蛋白粉之类的也是超加工食品。因此，超加工食品种类多样。

Completely unprocessed food is something basically straight from the farm or your garden, like a potato you just pulled from the ground.

完全未经加工的食物基本上是直接从农场或菜园中采摘的东西，比如刚从地里拔出来的土豆。

Processed food, in comparison, is everything kind of in between.

相比之下，加工食品介于两者之间。

So just washing a food can be a kind of processing. But so can chopping. And also things like canning, drying, and freezing.

清洗食物本身就是一种加工。切菜、罐装、干燥、冷冻都是一种加工。

How much of our diet is actually processed or ultra processed?

我们的饮食中有多少东西是经过加工、超加工的呢?

So by some estimates almost 60 percent of what we eat in the U.S. is ultra-processed.

据估计，我们在美国吃的几乎60%是超加工食品。

For kids, it's even worse — almost 70 percent of their diet is processed.

孩子的情况更糟，他们的饮食中，几乎有70%是加工食品。

Wow, that’s a lot. But does the amount and type of processing matter?

真的很多。不过，加工数量和加工类型有关系吗?

Yes. The differences in the intensity of processing are captured in something called the NOVA scale.

有关系。可以通过NOVA量表来体现加工强度的差异。

Does NOVA stand for something?

NOVA代表什么?

Nope, it’s actually just a name! “Nova” means “new” in Portuguese.

不代表什么，NOVA实际上只是一个名字! “Nova”在葡萄牙语中的意思是“新的”。

The system was developed in Brazil about a decade ago as a new way to categorize foods.

大约十年前，巴西开发了“Nova”系统，作为一种对食品进行分类的新方法。

Historically, scientists would look at foods in terms of the nutrients they contain, like protein, fat or carbohydrates.

过去，科学家们会根据食物所含的营养成分，如蛋白质、脂肪或碳水化合物，来看待食物。

NOVA sort of came about because scientists recognized that it’s not just nutrients that might affect the quality and health effects of food, but also the amount of processing they undergo.

Nova的出现在某种程度上是因为科学家们认识到，不仅营养物质可能影响食品的质量、对健康产生影响，而且食物所经过的加工量也会影响到这些。

So NOVA has four categories: there’s unprocessed or minimally processed food – which are things like eggs and vegetables.

NOVA系统分为四类。一类是未加工食品、或者说是经过最低限度加工的食品，比如鸡蛋、蔬菜。

Then there are foods you use to prepare meals but don’t necessarily eat on their own – like oil or butter.

一类是你用来准备饭菜的、但不会单独食用的食物，比如油、黄油。

Then there are processed foods, which you make using a combination of those categories – homemade bread, for example.

一类是加工食品，可以使用各类食品的组合来制作，比如，自制面包。

And the final category is ultra-processed foods, which involve industrial processing and additives.

最后一类是超加工食品，涉及工业加工和添加剂。

Almost everything we eat undergoes some amount of processing, right?

我们进嘴的几乎所有东西都要经过一定程度的加工，对吧?

Right, exactly. One example I’ve seen a lot is peanut butter.

是, 没错。我经常看到的一个例子是花生酱。

You could just crush up peanuts and get peanut butter—that’s minimally processed.

仅将花生碾碎，就做成了花生酱——这是最低限度的加工。

You could add salt, sugar, and oil, and get a processed version.

加入盐、糖和油，就可以得到一个加工版本的花生酱。

Or some of the peanut butter you find at the store could contain preservatives or emulsifiers, and that makes it ultra-processed.

你可以在商店里找到的一些花生酱可能含有防腐剂或乳化剂，这使得花生酱成为超加工食品。

So Lori, do we know if ultra-processed foods are bad for our health? What does the science say?

洛莉，超加工食品是否对我们的健康有害? 科学是怎么说的?

Some studies have found links between eating ultra-processed food and obesity, type 2 diabetes, some types of cancer and even mental health issues.

一些研究发现，食用超加工食品与肥胖、2型糖尿病、某些类型的癌症甚至心理健康问题之间存在联系。

But only a few studies have tried to measure whether it’s these diets that are causing the poor health.

但只有少数研究试图衡量这些饮食是否会导致健康状况不佳。

There’s one really important study from a few years ago that made a big splash in the research world because it actually compared the effects of an ultra-processed diet to a minimally processed one in a controlled setting.

几年前，一项非常重要的研究在学界引起了巨大轰动，因为这项研究是在控制环境下对比了超加工饮食和低限度加工饮食的影响。

Kevin Hall, a scientist at the National Institutes of Health recruited 20 volunteers and confined them to a hospital-like area in Maryland to study the effects of different diets.

美国国立卫生研究院的科学家凯文·霍尔为研究不同饮食的影响，招募了20名志愿者，并将他们关在马里兰州一个类似医院的地方。

Wait, wait, wait. They confined them there?!

等等，等等，等等，他们把志愿者关在那里?!

Yeah! I mean they could talk to one another and to the staff at the facility, but the idea was to prevent people from running off to the cafeteria to get food.

是啊! 我是说，志愿者之间可以互相交谈，他们也可以和场所里的工作人员交谈，这个主意是为了防止志愿者跑到自助餐厅吃饭。

For two weeks, some of them were given only minimally processed foods – so they would start their day with things like greek yogurt and fruit.

在两周的时间里，一些志愿者只会被提供经过最低限度加工的食品--他们会以希腊酸奶、水果等食物开始一天的生活。

Others got only ultra-processed foods, so things like a bagel with cream cheese, turkey bacon, and sugary breakfast cereals.

另一些志愿者只会被提供超加工食品，比如奶油芝士贝果、火鸡培根以及含糖早餐麦片。

And when each group finished those two weeks, they would switch to the other diet.

当每组志愿者这么吃了两周后，会切换到另一种饮食。

Participants were given as much food as they wanted.

实验参与者想要多少食物就提供多少。

And what’s interesting is that, on the ultra-processed diet, people actually ate about 500 calories more per day and ended up gaining about two pounds.

有趣的是，在超加工饮食组中，志愿者实际上每天会多摄入大概500卡路里，最终体重增加了大概2磅。

On the other hand, on the less processed meal plan it was the opposite: people tended to eat less and lost about two pounds as well.

另一方面，在较少加工饮食组中，情况正好相反：志愿者往往会吃得更少，体重也减轻了大概2磅。

Wow. So it seems like eating ultra-processed foods made people gain weight—even if the foods contained the same amount of nutrients as unprocessed foods. Why would that be?

哇。似乎吃超加工食品会让人发胖，即使这些食品含有与未加工食品相同的营养成分。为什么会这样?

Researchers aren’t really sure why, but there are a whole lot of theories.

研究人员并不确定是什么原因，但有很多解释的理论。

One is that ultra-processed foods tend to be more energy dense, meaning there are more calories per bite.

一是超加工食品往往能量密度更高，也就是说，每一口含有更多的卡路里。

Another possibility is we don’t feel as satiated by ultra-processed foods.

另一种可能性是，我们对超加工食品不会感到满足。

Right, they tend to have less fiber and protein – the things that fill us up and make food take longer to digest.

是的，超加工食品往往含有更少的纤维和蛋白质——这些物质饱腹感强，需要花更长时间才能消化掉。

They might also be harder to resist.

超加工食品可能也更难以抗拒。

Many ultra-processed foods contain a lot of fat, sugar, salt and carbs.

许多超加工食品含有大量糖、盐、脂肪和碳水化合物。

And that combination makes them hyperpalatable – basically, so tempting to us that we find it really hard to stop eating.

这种组合使得超加工食品变得无比美味——基本上可口诱人，我们会发现一吃就停不下来。

Those ingredients don’t exist together in nature – and some research has shown that the combination of fat and carbohydrates are better at activating the brain’s reward system compared to foods with just one of those things alone.

这些成分在自然界中并不会同时存在——一些研究表明，脂肪和碳水化合物的组合比单独含有其中一种成分的食物更能激活大脑的奖励系统。

And there’s newer research that’s finding ultra-processed food might be addictive.

最新研究发现，超加工食品可能会让人上瘾。

That all makes sense. But Lori, why are these foods so addictive? Is it even possible to be addicted to food?

这都有道理。但是洛莉，为什么这些食物会让人上瘾? 人们有可能对食物上瘾吗?

Yep. Think about it — you don’t lose control over eating bananas, but when was the last time you just ate ONE chip?

是的。想想看——你不会无法控制地吃香蕉，但你上次只吃了一片薯片是什么时候？

Basically never.

基本上没有只吃一片薯片的时候。

Right! That might be because of a dopamine spike it causes, similar to addictive substances like nicotine and alcohol.

没错! 这可能是因为它会引起多巴胺激增，类似于尼古丁和酒精等成瘾物质。

So are all ultra-processed foods really equivalent to one another, health-wise? Are canned vegetables really as bad for you as a glazed donut?

从健康的角度看，所有的超加工食品真的都一样? 罐装蔬菜真的和糖霜甜甜圈一样对人体有害吗?

It’s a little more complicated than that.

实际情况比这更复杂。

The reason some canned veggies are considered ultra-processed is because they might contain thickeners or firming agents like calcium chloride.

一些罐装蔬菜之所以被认为是超加工食品的原因是它们可能含有像氯化钙一样的增稠剂、固化剂。

But it’s probably not as unhealthy as, say, a sugary pastry.

但罐装蔬菜可能不会像含糖糕点那样不健康。

来源：经济学人