All nutrients come from the sun or the soil.

都來自太陽或土壤

Vitamin D, the "sunshine vitamin," is created when skin is exposed to sunlight.

維生素D是一種來自陽光的維生素

Everything else comes from the ground.

由皮膚接觸陽光生成

Minerals originate from the earth,

其他的養分都來自大地

and vitamins from the plants and micro-organisms that grow from it.

礦物質來自土壤

The calcium in a cow's milk (and her 200-pound skeleton)

維生素來自生長於土壤的植物和微生物

came from all the plants she ate, which drew it up from the soil.

乳牛的乳汁和其重達200磅的骨骼所含的鈣質

We can cut out the middle-moo, though, and get calcium from the plants directly.

都來自她所吃的植物 這些植物都取之於大地

Where do you get your protein?

而我們也可以省去中間的過程 直接從植物獲取鈣質

Protein contains essential amino acids,

那蛋白質又要從哪獲取呢？

meaning our bodies can't make them and so are essential to get from our diet.

蛋白質含有必需氨基酸

But other animals don't make them either.

表示人體無法自行生成 須經由食物取得

All essential amino acids originate from plants (and microbes),

但其他動物也同樣無法自行生成

and all plant proteins have all essential amino acids.

所有的必需氨基酸都來自植物和微生物

The only truly "incomplete" protein in the food supply is gelatin,

而所有植物性蛋白都含有全部的必需氨基酸

which is missing the amino acid tryptophan.

食品供應中

So the only protein source that you couldn't live on is Jell-O.

唯一真正「不完整」的蛋白質是明膠

As I covered previously, those eating plant-based diets

它缺乏色氨酸

average about twice the average daily requirement for protein.

所以 唯一一種不可靠的蛋白質來源就是...

Those who don't know where to get protein on a plant-based diet

果凍

don't know beans! Get it?

正如我之前提到的

That's protein quantity, though. What about protein quality?

採取蔬食的人

The concept that plant protein was inferior to animal protein

平均所需蛋白質的份量 為一般的兩倍

arose from studies performed on rodents more than a century ago.

不知道如何從蔬食中獲取蛋白質的人

Scientists found that infant rats don't grow as well on plants.

恐怕還不認識一種叫豆子的食物！瞭了嗎？

But infant rats don't grow as well on human breast milk either,

剛講的是蛋白質的量

so does that mean we shouldn't breastfeed our babies?

那蛋白質的「質」呢？

Ridiculous! They're rats.

過去有個說法

Rat milk has ten times more protein than human milk,

植物性蛋白遜於動物性蛋白

because rats grow about ten times faster than human infants.

這要追溯自「一百多年前」對齧齒動物進行的研究

It's true that some plant proteins are relatively low

當時科學家發現

in certain essential amino acids.

靠吃植物的幼鼠發育得並不好

So about 40 years ago, the myth of "protein combining" came into vogue—

但是 幼鼠喝人奶也是同樣的情形

literally: the February '75 issue of Vogue magazine.

依這樣來看 人類是否也不該喝母奶呢？

The concept was that we needed to eat "complementary proteins" together,

荒謬！ 兩者當然不能相提並論！

for example rice and beans, to make up for their relative shortfalls.

鼠奶中的蛋白質高於人奶十倍

This fallacy was refuted decades ago, the myth that plant proteins are incomplete,

因為老鼠的生長速度比人類嬰兒快約十倍

that plant proteins aren't as good, that one has to combine proteins at meals.

的確有些植物蛋白中的某種必需氨基酸含量較低

These have all been dismissed by the nutrition community as myths

所以在大約40年前

decades ago, but many in medicine evidently didn't get the memo.

蛋白質組合的迷思就「流行」了起來

Dr. John McDougall called out the American Heart Association

還真的上了《時尚》雜誌 1975年2月號期刊

for a 2001 publication that questioned the completeness of plant proteins.

其中的概念是

Thankfully though they've changed and acknowledged now

我們須要攝取能互補的蛋白質

that plant proteins can provide all the essential amino acids;

例如 米飯和豆類一起吃 以彌補彼此的短缺

no need to combine complementary proteins.

這樣的謬論 早在幾十年前便被駁斥

It turns out our body is not stupid.

「植物蛋白不完全」

It maintains pools of free amino acids that can be used

「植物蛋白品質較差」

to do all the complementing for us,

「蔬食者每餐都要有蛋白組合」

not to mention the massive protein recycling program our body has.

這些迷思早在幾十年前 就已被營養學界駁回

Some 90 grams of protein is dumped into the digestive tract every day

但許多醫學界裡的醫師 顯然都還沒收到通知

from our own body to get broken back down and reassembled,

約翰麥克杜格爾醫師不認同美國心臟病協會

so our body can mix and match amino acids to whatever proportions we need,

在2001年刊物中對植物蛋白完整性的質疑

whatever we eat, making it practically impossible to even design a diet

慶幸的是 他們目前已經作出校正

of whole plant foods that's sufficient in calories, but deficient in protein.

表示植物蛋白可提供所有必需氨基酸

Thus, plant-based consumers do not need to be AT ALL concerned about amino acid

不須要去組合能互補的蛋白質

imbalances from the plant proteins that make up our usual diets.

實際上 我們的身體並不笨