吃肉對你有害嗎？肉類真的不健康嗎？：英語精讀講義

When our vegetarian ancestors started eating meat around 2 million years ago,

當我們吃素的祖先在大約200萬年前開始吃肉時，

it wasn't just because animals taste great. 文法

並不只是因為肉的味道好。

It was pure necessity.

這完全是出於生存需要。

Climate change made many of the plants our ancestors relied on less available

氣候變遷導致我們祖先賴以生存的許多植物變得稀缺，

and meat bridged that gap. 慣用語

而肉類填補了這個空白。

From the discovery of fire at the latest, 片語搭配

最晚從發現火開始，

meat became a staple of the human diet. 用詞

肉類就成了人類飲食的主食。

But over the last few years,

但在過去幾年裡，

eating meat has increasingly been associated with health risks like heart disease, 片語搭配

吃肉越來越多地與心臟病等健康風險、

certain cancers,

某些癌症，

and an early death.

以及早逝聯繫在一起。

So, how unhealthy is meat really?

那麼，吃肉到底有多不健康呢？

In this video,

在這支影片中，

we'll only talk about meat.

我們只討論肉類。

Dairy products deserve a video of their own. 片語搭配

乳製品值得單獨做一支影片。

Biologically,

從生物學角度來說，

we need to eat for three reasons:

我們吃東西有三個原因：

for energy,

為了獲取能量，

to acquire materials to fabricate our cells

獲取製造細胞的物質，

and to get special molecules that our bodies can't make themselves.

以及獲取我們身體無法自行製造的特殊分子。

The energy and most of the materials come from the three macronutrients:

能量和大部分物質來自三大巨量營養素：

fats,

脂肪，

carbohydrates,

碳水化合物，

and proteins.

和蛋白質。

Proteins are the most important resource for repairing and replenishing our cell structures.

蛋白質是修復和補充我們細胞結構的最重要資源。

The special molecules are a large variety of vitamins and minerals we need to drive metabolic processes. 片語搭配

特殊分子是我們推動代謝過程所需的各種維生素和礦物質。

Meat provides us with most of these things. 片語搭配

肉類為我們提供了其中的大部分。

It contains all essential amino acids our body needs

它包含了我們身體所需的所有必需胺基酸，

and a lot of minerals like iron,

還有大量礦物質，如鐵、

zinc,

鋅，

and essential vitamins,

和必需維生素，

some of which are barely found in plants like vitamin B12. 文法

其中一些在植物中幾乎找不到，比如維生素B12。

Only one essential nutrient is missing in most of the meat we consume,

我們食用的大多數肉類中只缺少一種必需營養素，

vitamin C.

維生素C。

It appears in almost all plants and supports our immune system as well as the development of connective tissues. 片語搭配

它幾乎存在於所有植物中，支持我們的免疫系統以及結締組織的發育。

After a few months without it,

如果幾個月不攝取它，

you'd get scurvy.

你就會得壞血病。

But meat has another big advantage:

但肉類還有一個很大的優勢：

its high bioavailability. 用詞

其高生物利用度。

Some of the nutrients in meat are broken down faster and available quicker than those from plants. 片語動詞

肉類中的一些營養物質比植物中的營養物質分解得更快，也能更快被吸收。

Spinach,

菠菜，

for example,

舉個例子，

contains more iron than meat,

含有比肉類更多的鐵，

but it's absorbed much slower and the body needs more energy to digest it.

但它吸收得慢得多，且身體需要消耗更多能量來消化它。

Several health benefits have also been observed in communities that rely solely on meat.

在完全依賴肉類的社區中，人們也觀察到了一些健康益處。

The Inuit, 文化背景

因紐特人，

for example,

舉個例子，

are able to survive in extreme climate conditions on a purely meat-based diet,

能夠在極端氣候條件下，依靠純肉食生存下來，

if necessary.

如果有必要的話。

Since they consume the whole animal,

因為他們會吃掉整隻動物，

including the organs,

包括內臟，

they get every single nutrient they need,

他們獲得了所需的每一種營養素，

including vitamin C.

包括維生素C。

So,

所以，

meat itself is definitely not dangerous for us,

肉類本身對我們絕對不危險，

but its health effects vary depending on how it's prepared and what animal it comes from. 文法

但它的健康影響因烹調方式和肉類來源而異。

When talking about meat in the Western world, 文法

當在西方世界談論肉類時，

we generally mean muscle tissues that have a high nutrient density,

我們通常指的是營養密度高的肌肉組織，

but also lack some of the vitamins that make it possible to survive on meat alone. 文法

但它也缺乏一些能讓人僅靠吃肉生存的維生素。

The most healthy animals to eat are probably fish.

最健康的肉類可能就是魚了。

Fish contains polyunsaturated fatty acids like omega-3,

魚類含有多元不飽和脂肪酸，如Omega-3，

which may lower the risk of cardiovascular diseases and support anti-inflammatory immune functions.

可以降低患心血管疾病的風險，並支持抗炎的免疫功能。

As part of a balanced diet,

作為均衡飲食的一部分，

fish can be eaten regularly without worries.

可以經常吃魚而不用擔心。

Eating fish comes with its own bag of complications, 慣用語

不過吃魚也有其自身的一系列複雜問題，

though,

然而，

like overfishing and the destruction of the oceans.

比如過度捕撈和海洋生態破壞。

We'll talk about that in another video.

我們會在另一支影片中討論這個問題。

A close second is the most popular meat, 片語搭配

緊隨其後的是最受歡迎的肉類，

chicken.

雞肉。

It's regarded as the meat with the fewest health risks. 片語搭配

它被認為是健康風險最低的肉類。

The only negative health effect of poultry is a bit controversial,

禽肉唯一的負面健康影響存在一些爭議，

fat.

那就是脂肪。

Its high content of saturated fat is associated with a higher cholesterol level and cardiovascular disease.

其高飽和脂肪含量與較高的膽固醇水平和心血管疾病有關。

But this idea has also been criticized by a large number of scientists,

但這種觀點也受到了大量科學家的批評，

arguing high cholesterol levels might be inherited and not caused by nutrition. 文法

他們認為高膽固醇可能是遺傳的，而不是由飲食引起的。

So, in general,

所以，總的來說，

if you want meat and are concerned about your health,

如果你想吃肉又關心健康，

go for chicken. 片語動詞

就選雞肉吧。

Things start to get problematic with high intakes of red meats like beef,

當大量攝入紅肉時，事情就開始變得有問題了，比如牛肉、

veal,

小牛肉、

pork,

豬肉、

lamb,

羊肉、

horse,

馬肉，

and goat.

和山羊肉。

A recently published study recommends,

一項最近發表的研究建議，

for example,

舉例來說，

a maximum of 23 grams of red meat per day,

每天最多攝取23克紅肉，

which is a very small steak per week.

也就是每週一小塊牛排的量。

However,

然而，

large-scale meta-analysis studies have shown that eating 100 grams of red meat every day 用詞

大規模的薈萃分析研究表明，每天吃100克紅肉

increases the relative risk of diabetes by 19%, 用詞

會使患糖尿病的相對風險增加19%，

of strokes by 11%,

中風風險增加11%，

and of colorectal cancer by 17%.

大腸直腸癌風險增加17%。

This sounds alarming,

這聽起來很可怕，

but before we panic, 表達脈絡

但在我們恐慌之前，

let's have a look at how these studies were conducted.

讓我們看看這些研究是如何進行的。

Because this brings us to the second big problem 表達脈絡

因為這就引出了第二個大問題，

when trying to answer the question

當試圖回答這個疑問時，

of whether meat is unhealthy or not. 文法

即吃肉是否不健康。

Most studies that linked health risks to eating red meat

大多數將健康風險與吃紅肉聯繫起來的研究

were case-control studies, 文化背景

都是病例對照研究，

which means taking a group of people with a disease

意思是選取一群患有某種疾病的人，

and classifying them by their eating habits.

並根據他們的飲食習慣進行分類。

The more red meat they consume, 文法

他們攝取的紅肉越多，

the more likely they were to contract certain diseases.

感染某些疾病的可能性就越大。

The problem is that it's very hard to eliminate other factors. 用詞

問題是，很難排除其他因素。

People who eat less meat

吃肉較少的人

tend to live a healthier lifestyle in general. 文法

通常也會保持更健康的生活方式。

They tend to eat more vegetables and fruit

他們往往吃更多的蔬菜和水果，

and are less likely to smoke and drink alcohol. 文法

並且吸菸和喝酒的可能性更小。

Most studies try to eliminate these factors,

大多數研究試圖排除這些因素，

but it's extremely hard to make definitive statements. 片語搭配

但極難得出決定性的結論。

Things get worse when we look at processed

當我們看到加工

meat, though.

肉類時，情況就更糟了。

Processing meat means adding certain chemicals

加工肉類意味著添加某些化學物質，

by curing, 文法

透過醃製、

smoking,

煙燻、

salting,

鹽漬，

or fermenting.

或發酵。

Or,

或者，

in other words, 表達脈絡

換句話說，

making it delicious.

把它變得美味。

Bacon,

培根、

ham,

火腿、

salami,

薩拉米香腸、

sausages,

香腸，

and hot dogs contain chemicals that are harmful for us,

和熱狗含有對我們有害的化學物質，

like nitrates and nitrites

比如硝酸鹽和亞硝酸鹽，

that can damage the DNA in our digestive system

它們會破壞我們消化系統中的DNA，

and lead to cancer.

並導致癌症。

The WHO reviewed 800 studies over 20 years

世界衛生組織（WHO）審查了20年來的800項研究，

and concluded that processed meat is strongly linked to an increased risk of colorectal cancer. 片語搭配

得出結論：加工肉類與大腸直腸癌風險的增加密切相關。

Each extra 50 grams of processed meat per day increases your relative risk of cancer by 18%.

每天每多吃50克加工肉類，罹癌的相對風險就會增加18%。

When it comes to cancer risk,

在致癌風險方面，

processed meat is now in the same category as plutonium, 片語搭配

加工肉類現在與鈽、

asbestos,

石棉，

and smoking.

和吸菸同屬一類。

The WHO highlights that its research is only about the question of whether or not something causes cancer 文法

WHO強調，其研究只探討某物是否致癌，

and not to what extent.

而不是致癌的程度。

But processed meat may also significantly increase the chance of suffering from diabetes,

但加工肉類也可能顯著增加患糖尿病、

strokes,

中風，

and coronary heart diseases.

和冠心病的機率。

It also makes a difference what sort of life our meat lived 片語搭配

我們所吃的肉類在還是活物時經歷了怎樣的生活，這也有影響，

when it was still part of a living being.

當它還是一個生命體的一部分時。

It's common to feed large amounts of antibiotics to livestock in order to prevent diseases, 文法

為了預防疾病，給牲畜餵食大量抗生素是很常見的，

which can spread antibiotic resistance.

這會導致抗生素抗藥性的傳播。

Combined,

總結來說，

a high consumption of both red and processed meat

大量食用紅肉和加工肉類

could increase your chance of premature death by up to 29%. 用詞

會使你過早死亡的機率增加高達29%。

This means if your chance of dying is 3% this year,

這意味著，如果你今年的死亡機率是3%，

it's now 4%.

那麼現在就是4%。

This might not sound like a lot, 表達脈絡

這聽起來可能不多，

but tiny percentages have a huge impact on societies of millions.

但微小的百分比對數以百萬計的社會有巨大的影響。

They also seem harmless until they affect you.

在它們影響到你之前，它們看起來似乎是無害的。

To blame meat alone for bad health would be wrong, 文法

不過，把健康不佳完全歸咎於肉類是錯誤的，

though.

雖然。

There is no evidence that the very essence of meat has any negative effect beyond its high fat content,

沒有證據表明肉類本身的本質除了其高脂肪含量外，還有任何負面影響，

and even this point is highly contentious. 用詞

甚至這一點也是極具爭議的。

Just like with many other pleasures in life,

就像生活中的許多其他樂趣一樣，

sometimes too much of a good thing is harmful. 慣用語

有時好東西吃太多也會有害。

Most public health agencies suggest cutting meat consumption to 500 grams a week,

大多數公共衛生機構建議將肉類消費量減少到每週500克，

while studies suggest cutting down processed meat as much as possible.

而研究則建議盡量減少加工肉類的攝取。

So,

所以，

if you feast on meat no more than once or twice a week, 講解

如果你每週大快朵頤不超過一兩次，

you should be good. 語氣意圖

你應該沒問題。

For most people,

對於大多數人來說，

this already means a drastic change in their diets though.

這就已經意味著他們的飲食習慣發生了巨大的改變。

The average American consumes around almost 1,600 grams of meat a week.

一個普通的美國人平均每週消耗近1600克肉類。

The average German 1,100 grams a week. 文法

一個普通的德國人平均每週1100克。

And many of us eat much, 文法

而我們很多人吃得要多得多，

much more.

多得多。

If you're not really sure,

如果你不太確定，

make a small note whenever you eat meat for a week or two.

可以在一兩個星期裡，每次吃肉時做個小記錄。

You'll be surprised how much it really is.

你會驚訝地發現，你吃的量居然有那麼多。

So,

所以，

most people watching this video would benefit from cutting down on meat. 片語動詞

大多數觀看這支影片的人都會從減少吃肉中受益。

Aside from health concerns, 表達脈絡

除了對健康的擔憂，

there's still the fact that the meat industry is one of the largest contributors to climate change 文法

肉類工業還是導致氣候變遷的最大因素之一，

and has reached a scale 文法

並且其規模已經達到了這樣的程度：

where it's impossible to deliver millions of tons of meat

即不可能在提供數百萬噸肉類的同時

and still treat animals with dignity. 片語搭配

還能有尊嚴地對待動物。

We've already discussed that in detail in another video.

我們已經在另一支影片中詳細討論過這個問題。

All in all, 表達脈絡

總而言之，

in moderation, 片語搭配

適量食用，

meat is not unhealthy

肉類並不不健康，

and you don't need to become vegetarian overnight 用詞

你也不需要一夜之間變成素食主義者，

to have a real impact on your health and the planet.

就能對你的健康和地球產生實質性的影響。

But your lifestyle choices do matter for yourself and for others. 文法

但你的生活方式選擇，對你自己和他人來說，確實很重要。