哪些饮食法真的有效？：英语精读讲义

There are a lot of popular diets out there, 習語

市面上流行的饮食法有很多，

so we thought we'd create a simple video

所以我们想做一个简单的视频，

investigating which ones are scientifically sound and actually work. 短語搭配

看看哪些饮食法有科学依据，而且确实有效。

From the outside, 習語

乍看之下，

it seems like a simple equation.

这似乎就是一道简单的算式。

Your weight is determined by the balance between the calories you take in and the calories you burn.

你的体重取决于摄入热量与消耗热量之间的平衡。

By changing what you eat or your activity level,

只要改变饮食或活动量，

you can tip this equation towards weight gain or loss, 習語

就能让这道算式偏向增重或减重，

which brings us to our first category of diets,

这就引出了我们的第一类饮食法：

calorie restriction.

限制热量。

Companies like Weight Watchers claim you can eat whatever you want

Weight Watchers 等公司声称，你想吃什么都可以，

as long as you stay below a prescribed number of daily calories. 語法

只要每天不超过规定的热量即可。

Getting all your calories from junk food is technically allowed,

严格来说，全部热量都从垃圾食品中摄取也是允许的，

but from a health perspective, 短語搭配

但从健康角度看，

it's important to think about the nutritional value of the foods too.

也必须考虑食物的营养价值。

If you don't,

如果忽视这一点，

you risk heart problems,

你可能会面临心脏问题、

nutrient deficiencies,

营养缺乏，

and chronic health issues.

以及慢性健康问题。

Calorie restriction with optimal nutrition or CRON diets

最佳营养热量限制，也就是 CRON 饮食法，

generally reduce their caloric intake by 20% while still meeting the daily nutritional requirements.

通常会把热量摄入减少 20%，同时仍满足每日营养需求。

For example,

例如，

instead of having a whole apple,

与其吃一整个苹果，

a CRON dieter might just have the apple skin,

采用 CRON 饮食法的人可能只吃苹果皮，

which contains most of the nutrients.

因为大部分营养都在苹果皮里。

If used properly and not excessively, 語法

只要方法得当、不过度，

calorie restriction can be a safe and effective tool for weight loss.

限制热量可以成为安全有效的减重方式。

Next up is carb restriction. 表達脈絡

接下来是限制碳水化合物。

Many diets like the South Beach,

南海滩饮食法、

Atkins,

阿特金斯饮食法，

or Zone diets

或区域饮食法等许多饮食方案

suggest that carbs are the enemy of the fit body you've always dreamed of. 習語

都认为，碳水化合物是你实现梦寐以求的健美身材的大敌。

The ideology claims that when more carbs are taken in than burned off, 短語動詞

这种理念认为，当摄入的碳水多于消耗的量时，

the liver converts them into fats.

肝脏就会把它们转化为脂肪。

But for most healthy,

但对大多数健康、

reasonably active people,

活动量适中的人来说，

carbs are broken down to glucose and transported to the cells for energy. 短語動詞

碳水化合物会被分解成葡萄糖，再输送到细胞中供能。

Very little is actually turned into fat.

真正转化为脂肪的其实很少。

In response to excessive glucose, 短語搭配

面对过量的葡萄糖，

the body uses insulin to turn it into glycogen,

身体会借助胰岛素将其转化为糖原，

which is stored in the liver and muscles.

并储存在肝脏和肌肉中。

This glycogen may later be broken down in times of low glucose to refuel the body.

之后葡萄糖不足时，这些糖原可以分解，为身体补充能量。

But the type of carbs you eat do matter.

不过，你摄入的碳水化合物种类确实很重要。

Those from simple sugars like honey,

来自简单糖类的碳水，比如蜂蜜、

fruit,

水果，

or sugar are more readily turned into triglycerides or fat

或食糖，更容易转化为甘油三酯或脂肪，

than complex carbs like whole grains and veggies.

而全谷物和蔬菜等复杂碳水则没那么容易。

If you consistently eat way more than necessary 用詞

如果你一直吃得远超身体所需，

and most calories are from simple carbs,

而且大部分热量都来自简单碳水，

then these will be converted to fat.

这些碳水就会转化成脂肪。

Low-carb diets often have extreme restriction at first.

低碳水饮食法一开始往往限制得非常严格。

No starches like bread or pasta

不能吃面包、意面等淀粉类食物，

and no sugars including from fruits or even alcohol.

也不能摄入糖分，包括水果中的糖，甚至酒精。

This can lead to some intense side effects including constipation,

这可能导致一些强烈的副作用，包括便秘、

dry mouth,

口干、

bad breath,

口臭、

fatigue,

疲劳、

dizziness,

头晕，

and nausea.

以及恶心。

In studies,

研究显示，

carb restriction dieters tend to lose weight faster initially 語法

限制碳水的人在初期的减重速度，

compared to those simply using calorie restriction,

往往比单纯限制热量的人更快，

but this is likely due to water loss,

但这很可能是因为水分流失，

which returns in later phases when you're encouraged to eat normally again.

而到了后期，当你被鼓励恢复正常饮食时，这些水分还会回来。

On top of this,

除此之外，

the Atkins diet,

以阿特金斯饮食法

for example,

为例，

promotes caloric intake from high-fat and high-protein sources,

它鼓励从高脂肪、高蛋白食物中摄取热量，

which means meats,

也就是说，可以吃肉、

cheeses,

奶酪、

cream,

奶油、

butter,

黄油，

and losing weight.

还能减重。

Sounds pretty good, right? 語氣意圖

听起来很不错，对吧？

But many doctors show concerns over the high intake of saturated fat

但许多医生担心，摄入大量饱和脂肪

that it may lead to more bad cholesterol and therefore an increased risk of heart disease.

可能会增加坏胆固醇，进而提高患心脏病的风险。

Some claim these diets are dangerous and unhealthy

有人认为这些饮食法既危险又不健康，

given that they promote the limitation of foods like carrots, 語法

因为它们主张少吃胡萝卜、

sweet potatoes,

红薯，

or apples

或苹果

that provide the body with important micronutrients and vitamins.

这类能为身体提供重要微量营养素和维生素的食物。

Instead,

取而代之的是，

people require supplements,

人们需要服用营养补充剂，

which the body is not able to absorb as effectively as vitamins, 語法

但人体吸收这些补充剂的效率，比不上吸收天然完整食物中的维生素、

minerals,

矿物质，

and micronutrients in whole foods.

和微量营养素。

Then there are high-protein diets.

然后是高蛋白饮食法。

The main principle is that protein-rich foods are not as easily broken down by the body

它的核心原则是，富含蛋白质的食物不容易被身体分解，

and take more energy to digest than carb-rich food.

而且比富含碳水的食物需要更多能量来消化。

This means you won't feel hungry again as quickly

这意味着你不会那么快又感到饥饿，

and you're more likely to run a caloric deficit than if you ate the same number of calories from carbs. 講解

也比摄入等量碳水热量时更容易形成热量缺口。

The Paleo diet,

以原始人饮食法

for example,

为例，

suggests that 10,000 years ago agriculture was introduced

它认为农业在一万年前出现，

and the human diet changed from hunter-gatherers eating primarily meat,

人类的饮食也从狩猎采集者主要食用的肉类、

wild fruits,

野生水果、

veggies,

蔬菜，

and nuts

和坚果，

to diets containing more grains.

转变为含有更多谷物的饮食。

And as a result,

因此，

some believe the human body isn't designed to digest these processed foods like grains,

有人认为，人体并不适合消化这些加工食品，例如谷物、

dairy,

乳制品，

and breads.

和面包。

Some also believe that grains lead to inflammation-related health problems,

也有人认为谷物会引发与炎症有关的健康问题，

but this is largely untrue except in the case of people with celiac disease. 表達脈絡

但除了乳糜泻患者外，这种说法基本并不属实。

But because of its straightforward guidelines,

不过，由于它的规则简单明了，

many find it easy to follow 短語搭配

许多人觉得很容易遵循，

and it does promote more nutrient absorption.

而且它确实能促进更多营养的吸收。

However,

然而，

as Paleo cuts out all grains and legumes, 短語動詞

由于原始人饮食法排除了所有谷物和豆类，

we lose an important source of dietary fiber necessary to keep our bowels running smoothly. 語法

我们也会失去膳食纤维这一重要来源，而它是保持肠道顺畅运作所必需的。

Not to mention the high protein leads to nitrogen production, 表達脈絡

更别提高蛋白摄入还会产生氮，

meaning stinky farts.

也就是说，放的屁会很臭。

Add to that constipation,

再加上便秘，

which allows your digested material to sit longer in the large intestine

消化后的食物残渣会在大肠里停留更久，

and continuing to decompose and

还会继续分解腐败，而且……

yep,

没错，

even smellier farts.

屁会更臭。

There's another class of diets we might call the just-stop-eating diets. 表達脈絡

还有一类饮食法，可以叫作“干脆别吃了”饮食法。

Those looking to get slim quick might be tempted to only eat cabbage soup for 7 days 講解

想快速瘦下来的人，可能会忍不住连续 7 天只喝卷心菜汤，

or do the Master Cleanse diet,

或尝试 Master Cleanse 排毒法，

which only allows salt water in the morning

这种方法规定早上只能喝盐水，

and a concoction of water,

白天则喝一种由水、

maple syrup,

枫糖浆、

lemon,

柠檬，

and cayenne pepper through the day,

和辣椒粉调成的饮品，

and a laxative tea at night.

晚上再喝有泻药作用的茶。

But these diets are exceptionally unhealthy.

但这些饮食法极其不健康。

Not only is most of your weight loss from water weight,

你减掉的体重大多只是水分，

but there are many side effects such as dizziness,

还会出现许多副作用，例如头晕、

fatigue,

疲劳、

dehydration,

脱水，

and nausea.

和恶心。

The Master Cleanse can even lead to a white tongue,

Master Cleanse 排毒法甚至会让舌头发白，

which some claim is the toxins leaving your body,

有人声称这是毒素正在排出身体，

but it's actually due to swelling and a yeast infection of the mouth.

但其实是口腔肿胀和酵母菌感染造成的。

And after going through all that, 短語動詞

而经历这一切之后，

you're likely to gain any weight lost after stopping.

一旦停止，你很可能又会把减掉的体重全长回来。

Then,

然后，

of course,

当然，

there are straight-up crazy diets like eating cotton balls dipped in soup or juice 用詞

还有一些彻头彻尾的疯狂饮食法，比如吃蘸了汤或果汁的棉球，

so that you feel full,

让自己觉得饱，

which,

但这种东西，

of course,

当然，

provides hardly any nutritional content 語法

几乎没有任何营养，

and can cause intestinal blockages,

还可能导致肠梗阻，

which require surgical intervention. 用詞

必须通过手术处理。

Or how about the Sleeping Beauty diet where you just sleep? 語氣意圖

或者试试“睡美人饮食法”，什么都不做，只管睡觉？

You can't eat if you're always asleep.

如果一直在睡，当然就吃不了东西。

The truth is

事实是，

most diets focusing on quick,

大多数追求快速、

dramatic results

显著效果的饮食法

also have a yo-yo effect where you lose initial weight, 習語

也会产生溜溜球效应：一开始体重下降，

but slow down your metabolic rate,

但代谢率也会随之减慢，

so your body starts burning less calories.

于是身体消耗的热量越来越少。

And then when you start eating again,

等你重新开始进食，

there is all the weight back and often more.

体重就会全部反弹，往往还会比原来更重。

After following contestants from the show The Biggest Loser for 6 years,

在对《The Biggest Loser》节目的参赛者追踪 6 年后，

some of which who had lost hundreds of pounds in those 7 months,

其中一些人曾在那 7 个月里减掉数百磅，

scientists noticed something interesting.

科学家注意到了一个有趣的现象。

Not only did most of the participants in the study regain their weight, 語法

研究中的大多数参与者不仅体重反弹，

but their metabolic rates changed.

代谢率也发生了变化。

One man in particular now burns 800 fewer calories a day 語法

其中一名男性现在每天消耗的热量少了 800 卡路里，

than would be expected for a man his size.

低于同等体型男性的预期水平。

This is 6 years after leaving the show,

而这还是在他离开节目 6 年之后，

showing how extreme measures to lose weight, 表達脈絡

说明用极端手段减重，

while they may be successful at the time, 語法

即使当时可能成功，

have long-lasting impacts on your metabolism, 短語搭配

也会对新陈代谢造成长期影响，

making it harder to keep off weight in the future. 講解

让你日后更难维持减重成果。

The hard truth is 表達脈絡

残酷的事实是，

that even using many of the principal diets,

即使采用许多主流饮食法，

about 97% of people regain everything lost

约有 97% 的人会重新长回减掉的全部体重，

and sometimes more within 3 years.

有时甚至会在 3 年内变得更重。

If you want to lose weight,

如果你想减重，

finding a diet that works for you 講解

找到适合自己的饮食方式，

and keeps you motivated with small incremental changes is important. 短語搭配

并通过循序渐进的小改变保持动力，非常重要。

Of course,

当然，

a number on a scale doesn't measure how healthy a person is, 語法

体重秤上的数字并不能衡量一个人是否健康，

though many struggle with this perception.

尽管很多人都难以摆脱这种观念。

If food and weight preoccupations are a problem for you or someone you know, 用詞

如果你或你认识的人因过度关注食物和体重而困扰，

check out the description of this video for links with more information.

请查看本视频简介，其中附有提供更多信息的链接。

And subscribe for more weekly science videos.

想看每周更新的科学视频，别忘了订阅。