When our vegetarian ancestors started eating meat around two million years ago,
it wasn’t just because animals taste great,
it was pure necessity.
Climate change made many of the plants our ancestors relied on less available
and meat bridged that gap.
From the discovery of fire at the latest,
meat became a staple of the human diet.
But over the last few years
eating meat has increasingly been associated with health risks like:
heart disease, certain cancers, and an early death.
比如心脏病 某些癌症 早逝
So how unhealthy is meat, really?
In this video we’ll only talk about meat.
Dairy products deserve a video of their own.
Biologically, we need to eat for three reasons:
for energy, to acquire materials to fabricate our cells,
and to get special molecules that our bodies can’t make themselves.
The energy and most of the materials come from the three macronutrients: fats, carbohydrates and proteins.
Proteins are the most important resource for repairing and replenishing our cell structures.
The special molecules are a large variety
of vitamins and minerals we need to drive metabolic processes.
Meat provides us with most of these things.
It contains all essential amino acids our body needs
and a lot of minerals like:
iron, zinc and essential vitamins,
some of which are barely found in plants like Vitamin B12.
Only one essential nutrient is missing in most of the meat we consume: vitamin C.
It appears in almost all plants and supports our immune system
as well as the development of connective tissues.
After a few months without it you’d get scurvy.
But meat has another big advantage, it’s high bioavailability.
Some of the nutrients in meat
are broken down faster and available quicker than those from plants.
Spinach for example, contains more iron than meat,
but it’s absorbed much slower
and the body needs more energy to digest it.
Several health benefits have also been observed in communities that rely solely on meat.
The Inuit for example,
are able to survive in extreme climate conditions thanks to a purely meat-based diet.
Since they consume the whole animal including the organs,
they get every single nutrient they need
including vitamin C.
So meat itself is definitely not dangerous for us.
But its health effects vary,
depending on how its prepared and what animal it comes from.
When talking about meat in the Western world,
we generally mean muscle tissues that have a high nutrient density,
but also lack some of the vitamins
that make it possible to survive on meat alone.
The most healthy animals to eat are probably fish.
Fish contains polyunsaturated fatty acids like omega-3,
which may lower the risk of cardiovascular diseases and support anti-inflammatory immune functions.
As part of a balanced diet, fish can be eaten regularly without worries.
Eating fish comes with its own bag of complications though,
like overfishing and the destruction of the oceans.
We’ll talk about that in another video.
A close second is the most popular meat, chicken.
It’s regarded as the meat with the fewest health risks.
The only negative health effect of poultry is a bit controversial:
Its high content of saturated fats is associated
with a higher cholesterol level and cardiovascular disease.
But this idea has also been criticized by a large number of scientists
arguing high cholesterol levels might be inherited and not caused by nutrition.
So in general, if you want meat and are concerned about your health,
go for chicken.
Things start to get problematic with high intakes of
red meats like beef, veal, pork, lamb, horse and goat.
像牛肉 小牛肉 猪肉 羔羊肉 马肉和山羊肉
A recently published study recommends for example
a maximum of 23 grams of red meat per day
which is a very small steak per week.
However，large-scale meta-analysis studies have shown that
eating 100 grams of red meat every day
increases the risk of diabetes by 19 %,
of strokes by 11 % and of colorectal cancer by 17 %.
This sounds alarming.
But before we panic,
let’s have a look at how these studies were conducted.
Because this brings us to the second big problem
when trying to answer the question of whether meat is unhealthy or not.
Most studies that linked health risks to eating red meat were case-control studies.
Which means taking a group of people with a disease
and classifying them by their eating habits.
The more red meat they consume,
the more likely they were to contract certain diseases.
The problem is that it’s very hard to eliminate other factors.
People who eat less meat tend to live a healthier lifestyle in general.
They tend to eat more vegetables and fruit
and are less likely to smoke and drink alcohol.
Most studies try to eliminate these factors,
but it’s extremely hard to make definitive statements.
Things get worse when we look at processed meat though.
Processing meat means adding certain chemicals
by curing, smoking, salting or fermenting
把肉类进行腌制 烟熏 盐渍或者发酵
or in other words making it delicious.
Bacon, ham, salami, sausages and hot dogs
培根 火腿 腊肠 香肠 热狗
contain chemicals that are harmful for us
like nitrates and nitrites that can damage the DNA
in our digestive system and lead to cancer.
The WHO reviewed 800 studies over 20 years,
and concluded that processed meat is strongly linked
to an increased risk of colorectal cancer.
Each extra 50 grams of processed meat per day
increases your risk of cancer by 18 percent.
When it comes to cancer risk,
processed meat is now in the same category as plutonium, asbestos and smoking.
加工肉类和钚 石棉 吸烟的影响不相上下
The WHO highlights that its research is only
about the question of whether or not something
causes cancer and not to what extent.
But processed meat may also significantly increase the chance of
suffering from diabetes, strokes and coronary heart diseases.
It also makes a difference what sort of life our meat lived
when it was still part of a living being.
It’s common to feed large amounts of antibiotics to livestock
in order to prevent diseases
which can spread antibiotic resistance.
Combined, a high consumption of both red and processed meat
could increase your chance of premature death by up to 29%.
This means if your chance of dying is at 3 % this year,
it’s now 4 %.
This might not sound like a lot
but tiny percentages have a huge impact on societies of millions.
They also seem harmless until they affect you.
To blame meat alone for bad health would be wrong though.
There is no evidence that the very essence
of meat has any negative effect beyond it’s high fat content.
And even this point is highly contentious.
Just like with many other pleasures in life,
sometimes too much of a good thing is harmful.
Most public health agencies suggest
cutting meat consumption to 500 grams a week
while studies suggest cutting down processed meat as much as possible.
So if you feast on meat no more
than once or twice a week, you should be good.
For most people this already means
a drastic change in their diets though,
The average American consumes around almost 1600 grams of meat a week.
The average German 1100 grams a week.
And many of us needs much much more.
If you’re not really sure,
make a small note whenever you eat meat for a week or two.
那么在一个或两个星期内 你一旦吃肉 就记录下来
You’ll be surprised how much it really is.
So most people watching this video would benefit from cutting down on meat.
Aside from health concerns,
there’s still the fact that the meat industry
is one of the largest contributors to climate change
and has reached a scale where
it’s impossible to deliver millions of tons of meat
and still treat animals with dignity.
We’ve already discussed that in detail in another video.
All in all, in moderation,
meat is not unhealthy and you don’t need to become vegetarian overnight
to have a real impact on your health and the planet.
But your lifestyle choices do matter.
For yourself and for others.
The key is being open to trying something new once in a while.
Maybe you’ll discover your new favourite dish.
Until you try you’ll never know what you’ll enjoy or what you’re capable of.
Maybe after watching hours of Kurzgesagt videos,
you’ve decided you’d like to learn how to animate.
Now you might not know this,
but most of our team actually has a graphic design background.
Learning about design principles first before
we got into animation was really key to where we are today.
There’s a really great new Skillshare class on using Adobe Illustrator,
The software we use to create artwork
by graphic designer Aaron Draplin
and we can personally recommend it.
It’s full of great tips to help understand and simplify a very complicated program.
If you want to do more afterwards,
we have three animation courses of our own on Skillshare too.
Skillshare offers over 25,000 classes on topics
like film and video editing, writing,
包含了许多资深专家在电影 视频编辑 写作
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When our vegetarian ancestors started eating meat around two million years ago,