What Actually Happens When You Are Sick?

Kurzgesagt – In a Nutshell
28 Feb 202311:12

Summary

TLDRThe immune system fights disease aggressively, often damaging the body. Repeated infections can cause permanent scarring and loss of organ function over time. Vaccines safely train immune defenses without harming the body, providing better protection than natural infection in most cases. Individual immune responses vary; the healthiest can still die from new diseases. Climate change is another solvable global crisis requiring cooperation.

Takeaways

  • 😊 Getting sick can make you weaker in the long run by damaging organs and leaving scars
  • 👮‍♂️ Your immune system mobilizes like an army switching to war economy when you get sick
  • 🔥 Methods like fever are draining and use up resources needed for recovery
  • 😠 Both infections and immune cells can damage organs, leaving permanent scars
  • 😥 Cumulative scarring over a lifetime can diminish organ function
  • 🎖️ Surviving an illness gives you immune memory to fight it better next time
  • 💉 Vaccines train immune memory safely without real weapons that risk damage
  • 🥋 Vaccines are a safer 'dojo' than real infections to gain immunity
  • 🌟 Vaccines tap into immune memory creation more productively than nature
  • 😎 Overcoming disease for good is possible if humanity works together

Q & A

  • What happens in the body when you get sick?

    -When you get sick, your body activates an immune response, releasing signals like cytokines that trigger sickness behaviors like fatigue and loss of appetite. Your body also breaks down muscle to fuel the demanding immune response.

  • Why can getting sick make you weaker?

    -Activating a strong immune response places great demands on the body, burning calories and amino acids. In weakened patients, just keeping the immune system going can overtax the body's capacities. The immune response can also cause collateral damage like scarring.

  • How can your immune system damage your own body?

    -Immune cells like neutrophils release harsh chemicals to kill invaders that can also damage healthy tissue. Infections themselves release toxins and cause tiny wounds in organs. Repairing this damage can leave non-functional scar tissue.

  • Why is each person's immune system unique?

    -Everyone has a slightly different immune system that's stronger or weaker against certain pathogens. This spectrum protects humans from being wiped out by any one disease.

  • What are the risks of relying on "nature's dojo" for immunity?

    -Getting sick to gain natural immunity can lead to scarring, permanent organ damage or even death. You never know how severe an infection will be based on your unique immune response.

  • How do vaccines tap into the immune system's memory?

    -Vaccines mimic disease to train immune memory without real infection. This creates memory cells ready to respond if the real pathogen arrives later, for milder illness.

  • How can vaccines provide better immunity than nature?

    -Vaccines are engineered to optimally engage immune defenses. The resulting vaccine-induced immunity can be better than natural immunity gained from fighting actual disease.

  • What are limitations of vaccines?

    -No vaccine provides 100% protection. Pathogens can mutate quickly to evade vaccines. Some people also respond less effectively to vaccines and gain less immune memory from them.

  • How has medical progress impacted disease mortality rates?

    -Thanks to progress over the past century in areas like sanitation, vaccines, and treatment, humanity has made dramatic strides against infectious disease and related mortality.

  • What can individuals do to boost immunity without risk?

    -Getting vaccinated allows people to safely train immune defenses against disease without real infection. This builds protective memory cells to fend off pathogens.

Outlines

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Mindmap

Keywords

💡immune system

The immune system is your body's defense against infections and diseases. The video explains how it mobilizes against invaders but can also cause damage. Vaccines help train it without harm.

💡cytokines

Signaling proteins released by cells to activate immune responses. Their amplification can lead to widespread inflammation.

💡fever

Increases metabolism to fight infection. Helpful but also stressful and draining.

💡neutrophils

Aggressive immune cells that kill invaders but can also damage healthy tissue.

💡scars

Collagen deposits that patch damage but reduce organ function over time.

💡vaccines

Safely train immune memory without risk of disease damage. Still can have side effects.

Highlights

The idea that what doesn't kill you makes you stronger is challenged; sometimes, it makes you weaker.

The body is likened to a country at war, defending against invading pathogens with a sophisticated immune response.

Cytokines act as alarm signals, triggering immune defenses and causing sickness behavior to conserve energy for fighting off infection.

The immune system's demand for energy and resources during an infection is likened to a war economy, with significant disruption and drain.

Serious infections can lead to the body breaking down muscle tissue for energy, highlighting the intense demands of immune responses.

The immune system can cause collateral damage to the body, illustrating the delicate balance between fighting infection and causing harm.

Infections can lead to permanent organ damage and decreased functionality, with repeated serious diseases potentially impacting quality of life.

Vaccines are presented as a way to train the immune system, mimicking disease to create memory cells without the risk of actual sickness.

The analogy of 'vaccine dojo' vs. 'nature dojo' is used to compare the safer, controlled immune training of vaccines to the unpredictable risks of natural infections.

Vaccine immunity is often stronger and safer than natural resistance, emphasizing vaccines as a critical tool for immune system training.

The transcript acknowledges the limitations of vaccines but underscores their importance in enhancing natural defenses against diseases.

The potential for humanity to overcome diseases through scientific progress, including vaccination, is highlighted as a key goal.

The importance of addressing climate change alongside other global challenges like disease is emphasized, with a call to action for individual and collective efforts.

A partnership with Wren to offset carbon emissions is introduced, illustrating a practical step individuals can take against climate change.

The transcript concludes with an encouragement to continue learning about the immune system and to support efforts against climate change, reflecting a broader perspective on global challenges.

Transcripts

play00:00

There is this idea floating around that what doesn’t kill you, makes you stronger.

play00:05

That surviving a disease leaves you better off.

play00:07

And it seems to make sense because we have all experienced this.

play00:11

When you go through hardship, often you come out more resilient, more ready to face a difficult

play00:15

situation in the future.

play00:17

But it turns out that sometimes, what doesn’t kill you makes you weaker.

play00:22

So, what happens when you get sick?

play00:34

The Machinery of War

play00:36

Think of yourself as a large country, with a sizable army to defend it.

play00:40

You are surrounded by enemies that want to take your land, your energy, your resources.

play00:46

This is a matter of life and death, so your body evolved to be sensitive to damage and

play00:50

to the presence of enemies.

play00:52

Because this means that an invasion might happen at any moment and that it has to act

play00:56

fast.

play00:57

Let us start an invasion and see what happens.

play01:01

The moment your cells notice that something is off, they release an onslaught of signal

play01:06

proteins called cytokines.

play01:07

They are like air raid sirens that activate all sorts of immune cells, that then themselves

play01:13

release many more cytokines, amplifying the alarm.

play01:16

Soon you are flooded with signals that trigger precautions and counter-measures.

play01:21

Mobilization is under way.

play01:23

Your brain activates sickness behavior and reorganizes your body's priorities to defense.

play01:29

The first thing you notice is that your energy level drops and you get sleepy.

play01:33

You feel apathetic, often anxious or down and you lose your appetite.

play01:38

Your sensitivity to pain is heightened and you seek out rest.

play01:41

All of this serves to save your energy and reroute it into your immune response.

play01:47

You become a country under attack switching into a war economy, because properly activating

play01:52

your immune system is intensely disruptive and draining.

play01:56

Just like war is expensive for a country as industry switches to building tanks, your

play02:01

immune system demands huge amounts of energy, amino acids and micro elements to build its

play02:06

weapons.

play02:07

Take fever: it speeds up your metabolism and makes your cells work harder and faster, while

play02:12

creating heat that is pretty stressful for many invaders – but it uses up a lot of

play02:17

calories to maintain.

play02:19

Then your immune system begins to clone millions of specialized immune cells to respond specifically

play02:24

to the enemy infecting you.

play02:26

B Cells produce millions of antibodies every second, each requiring hundreds of amino acids

play02:31

to construct.

play02:33

Billions or even trillions of proteins need to be made to refresh the complement system,

play02:37

a minefield inside your blood.

play02:40

Cytokines, the mobilisation and information signals, also need constant refreshing.

play02:46

Usually you acquire your resources by eating.

play02:49

But when you are sick, your body slows down your digestion because it needs a lot of energy

play02:53

you can’t spare.

play02:54

So it reaches for the easiest source of amino acids and starts breaking down your muscles.

play03:00

All that muscle that you worked so hard for is sacrificed to keep you alive.

play03:06

If you are young and healthy and fit, you will make up for that quickly once you are

play03:09

better.

play03:10

But if you are old or very young, weak or suffer from chronic illness, this may be way

play03:15

too draining.

play03:16

Your body is literally consuming itself to keep the defense going.

play03:20

If your whole system is already strained, when you get sick, just keeping your immune

play03:24

responses going can overwhelm your capacities.

play03:28

Your Immune System is a Jerk.

play03:30

Our enemies too.

play03:32

Your immune system is as dangerous to you as it is to enemies.

play03:36

There is a very fragile balance between the damage caused by an infection and the collateral

play03:41

damage caused by immune cells.

play03:43

One of your first responders are Neutrophils – imagine crazy aggressive chimps with machine

play03:48

guns.

play03:49

If a Neutrophil encounters enemies it showers them with chemicals that cut them open but

play03:54

can also damage civilian cells, especially if the patient is already compromised, for

play03:59

example by smoking.

play04:01

On top of that the microorganisms that invade you often release chemicals and toxins that

play04:06

can cause significant damage and cell death.

play04:09

So a serious infection often causes many tiny wounds, literally holes in your organs.

play04:15

As you can imagine it is not great to have holes and wounds in your organs, and your

play04:19

body rushes to close them.

play04:21

Your Neutrophils and Macrophages help by releasing chemicals that signal the body to start repairs,

play04:27

and most of the damage is quickly filled up with regrowing cells.

play04:30

But others are filled with collagen, a sort of fix-all organic cement that gives your

play04:35

gooey tissue structural integrity.

play04:37

You have seen the result on your skin as scars.

play04:40

A scar is different from the original tissue.

play04:43

It has no functioning cells in it, it is like a sloppily applied cement patch.

play04:47

It can’t do what the original tissue was doing.

play04:50

A scar on your heart makes it beat a tiny bit weaker.

play04:54

A scar on the lungs no longer captures oxygen.

play04:57

A scar on your liver makes it a worse filter.

play05:01

And so, as you go through life and survive serious disease after serious disease, the

play05:05

functionality of your organs may decrease.

play05:07

This damage is usually small enough not to affect your quality of life – but can be

play05:13

permanent.

play05:14

Ok, this sounds depressing, but there is actually something you can do to avoid a lot of this

play05:18

damage and train your immune system!

play05:22

The best way to train your Immune System

play05:25

Your immune system is unique.

play05:27

Everyone has a slightly different immune system that’s stronger against some enemies and

play05:31

weaker against others.

play05:32

Which makes evolutionary sense, as this protects our species from being wiped out by a single

play05:37

infection.

play05:38

Collectively, the immune system of the human species is a spectrum: most people respond

play05:43

well enough to an infection, a few are super-responders and a few don't respond well and die.

play05:49

Some people survived the black death, are more resistant to HIV or Corona virus or even

play05:55

resistant against Ebola.

play05:56

Others are killed easily by the flu or highly vulnerable to certain bacterial infections.

play06:02

Where you are on this spectrum is impossible to predict.

play06:06

And you also respond differently to every possible infection.

play06:10

This is why seemingly very healthy young people died from Covid while for some elderly people

play06:15

it was more like a mild flu.

play06:18

The idea that you can weather all sorts of diseases if you never get a cold is wrong.

play06:22

You never know what your immune system is good at until it is tested.

play06:27

Getting sick is a gamble in life’s casino with your health on the line.

play06:32

Always.

play06:33

But there is something you can do: hacking one of the best features of your immune system.

play06:38

When you survive a disease, usually you have better defenses against it afterwards – you

play06:43

gain memory cells that are very good at killing the specific enemy you fought that day.

play06:47

So you either don’t get the disease again or the next infection is much milder.

play06:52

And you can use an incredible achievement of human ingenuity that taps into this mechanism

play06:57

to prevent damage from disease and train your immune system: Vaccines.

play07:03

Vaccines basically pretend to be a disease and train your defenses to be ready if it

play07:07

ever shows up for real.

play07:09

The goal is to create the same memory cells that you would get after surviving an infection.

play07:14

But if you can feel some side effects, why should you still do it?

play07:19

Nature Vs Vaccine Dojo

play07:22

You have two options to train your immune system: Vaccine Dojo and nature dojo.

play07:28

In vaccine dojo you train with paper weapons and learn to defend yourself.

play07:33

Sure, you might get a black eye or a bruise.

play07:37

Sometimes after a vaccine, you get sick for a few days, but that’s generally it.

play07:41

No scars, no permanent damage.

play07:43

We discussed vaccine side effects in detail in another video if you want to learn more.

play07:48

On the other hand, getting a disease to become immune means going to a nature dojo.

play07:52

In nature dojo, you train with real weapons, sharp knives and swords.

play07:58

Things might still work out, but with way more cuts and wounds.

play08:02

But from time to time someone will die, be it a kid from measles or an adult from influenza.

play08:08

Nature dojo is just way more risky.

play08:11

On top of that, the immunity you get from a vaccine is often better than the natural

play08:15

resistance, because they are engineered to engage your immune system in a more productive

play08:20

way.

play08:21

Of course vaccines are not magic and sometimes they do not protect us as well as we’d like

play08:25

them to.

play08:26

Maybe because an enemy mutates too quickly, like the Omicron coronavirus, or because your

play08:31

specific immune system does not respond well to the vaccine and builds less of a defense.

play08:36

Still, being vaccinated is one of the best tools to train your natural defenses.

play08:42

In the end, if we look at the stunning progress humanity has made in the last century, eventually

play08:47

we may overcome disease for good.

play08:50

But until then we can do our best to take care of ourselves and others - your body and

play08:55

your older self will be grateful to you.

play09:00

Diseases are not the only problem humanity can address if we work together.

play09:04

We believe the same is true for climate change, one of the main challenges of our generation.

play09:08

We are very passionate about this topic and we have covered it extensively in previous

play09:13

videos.

play09:14

Humanity needs to tackle this problem on different levels of society, from governments and economies

play09:18

down to the individual.

play09:20

And there’s one way you can take action now – by working with our friends from Wren,

play09:25

who help you offset your carbon emissions.

play09:27

By visiting wren.co and answering a few questions you can find out what your personal carbon

play09:31

footprint is.

play09:33

Your first step should be reducing your footprint – but there are limits to that.

play09:38

Wren lets you offset the rest of your carbon footprint with a monthly subscription that

play09:42

supports projects that plant trees, protect rainforests, and remove carbon dioxide from

play09:47

the sky.

play09:48

We think it's one of many puzzle pieces that can make a real difference in the climate

play09:50

crisis.

play09:51

Once you sign up to make a monthly contribution you’ll get pictures and updates from the

play09:55

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play09:59

We appreciate Wren’s focus on transparency and impact, so you can always retrace how

play10:04

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play10:05

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play10:10

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play10:13

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play10:17

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play10:18

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play10:23

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play10:27

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play10:31

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play10:36

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play10:40

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play10:44

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play10:46

Learn more about immune cells and marvel at the battles that are fought in your body everyday.

play10:51

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