What Actually Happens When You Are Sick?

Summary

The video explores how infections can overwhelm and permanently damage the body's immune system, especially in the elderly or chronically ill. It explains how immune responses like fever and inflammation defend against disease but also tax the body. Repeated infections scar tissues and strain organs over time. Vaccines safely train immunity without harming the body like real infections do, making them vital for protecting health. Though imperfect, vaccines remain one of our best tools for preventing disease until science can overcome it completely. Individual action like carbon offsets can also drive progress on global threats like climate change.

Takeaways

• 😣 When you get sick, your body goes into crisis mode to fight the infection, which is draining and can cause damage
• 😡 Immune cells and pathogens release chemicals that cause collateral damage to your own cells during infection
• 🤕 Repeated infections can leave behind scar tissue that reduces organ function over time
• 😎 Your immune system is unique - you may be resistant to some diseases but vulnerable to others
• 😃 Vaccines safely train your immune system by mimicking infections, with less risk than getting sick
• 👍 Vaccines provide targeted immune memory against specific pathogens for better protection
• 🤔 Sometimes vaccines don't work as well due to mutations or individual differences
• ⚔️ Getting sick is risky - you don't know how your immune system will respond until tested
• 🌳 Offsetting carbon emissions can make a real difference against climate change
• 😊 Understanding the immune system helps us design better treatments and take better care of ourselves

Q & A

What happens in the body when you get sick?

When you get sick, your body releases cytokines which activate immune cells and trigger sickness behaviors like low energy, anxiety, pain sensitivity, and loss of appetite. This prioritizes your body's resources for fighting the illness.

How does fever help your immune system?

Fever speeds up your metabolism, making your cells work harder and faster. This creates heat that is stressful for invaders, but it uses a lot of calories to maintain.

Why can getting sick make you weaker?

Activating your immune system requires breaking down muscle for amino acids to build immune cells. This damage may not fully recover, especially in the elderly or chronically ill. Infections also leave collagen scars that reduce organ function.

How can your immune system damage your own body?

Immune cells like neutrophils release chemicals that damage both invading cells and your own cells. Infections also release toxins that cause cell death and holes in organs, which leave collagen scars during healing.

What is the advantage of getting immunity through a vaccine rather than natural infection?

Vaccines train your immune system without real weapons, so there is less damage. The immunity from vaccines can also be better engineered to create productive memory cells.

Why might vaccines not always fully protect you?

If a virus mutates significantly like Omicron, vaccines may not prepare your immune system as well. Or someone's immune system may not respond strongly enough to a particular vaccine.

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

Vaccines mimic disease antigens to create memory cells that are ready to kill those antigens if the real disease infects you later, resulting in milder or no symptoms.

What personal action can you take related to climate change?

You can work with Wren to measure and offset your carbon footprint by supporting projects that remove carbon dioxide and plant trees.

How do old refrigerators contribute to climate change?

Old refrigerators use coolant gases that, once released, cause global warming thousands of times faster than CO2. Wren's project destroys these gases so they can't leak.

What might humanity overcome regarding disease in the long term?

If vaccination and medical progress continue, humanity may eventually overcome many diseases that currently cause damage and death.

Outlines

00:00

😷 How Infections Can Actually Make You Weaker

When you get sick, your body activates your immune system to fight the infection. This requires a lot of energy and resources, so your body breaks down muscles and other tissues. This causes damage that is repaired with collagen scars, which are not as functional as original tissue. So each new infection causes a little more accumulated damage, gradually decreasing the functionality of your organs over time.

05:01

😀 Vaccines Train Your Immune System Without Damage

Vaccines tap into your immune system's ability to build defenses against diseases you've survived before. They train your immune cells against a disease without the collateral damage of actual infection. So vaccines are like training in a safe "dojo" compared to risky "real fight" exposure from getting sick.

10:04

🌳 Offset Your Carbon Footprint

Climate change is an urgent problem requiring action across society. An impactful step individuals can take is using Wren to analyze then offset their carbon footprint by supporting projects that remove carbon dioxide. Kurzgesagt will pay the first month for the first 200 people who sign up.

Keywords

💡immune system

The immune system is the body's defense mechanism against infections and diseases. It is compared to an army that protects a country. The video explains how the immune system mobilizes a complex response when the body is invaded by pathogens. This drains energy and resources and can cause damage. Examples are given such as fever, antibody production, complement system activation etc.

💡cytokines

Cytokines are signaling proteins released by immune cells to trigger an inflammatory response. The video describes them as "air raid sirens" that amplify the alarm and lead to a flood of signals mobilizing defense mechanisms. They need constant replenishing during an immune response.

💡inflammation

Inflammation is the body's defensive response to harmful stimuli. The video portrays it as the war economy that a country switches to when under attack. Inflammation helps fight infection but also causes collateral damage. The associated symptoms like pain, fever and fatigue allow the body to focus energy on attacking the pathogen.

💡fever

Fever is an important part of the inflammatory defense mechanism. The video explains that it speeds up metabolism to create heat that stresses invaders. But fever also uses up calories and is resource-intensive for the body to maintain.

💡immune memory

When the immune system encounters a pathogen, memory cells are created that recognize that specific antigen in the future. The video states that surviving a disease creates better defenses against it afterwards. Immune memory is key to vaccines conferring protection.

💡vaccines

Vaccines train the immune system by imitating disease and creating memory cells, but without causing permanent damage. The video compares them to a "dojo with paper weapons" that prepares defenses without the harm of real infections that are like "training with knives".

💡scarring

Infections and the resulting inflammation often cause tiny wounds and cell damage. As part of the healing process, collagen fibers fill up the wounds leading to non-functional scar tissue. The video warns that accumulating scars on organs over a lifetime can decrease their functioning.

💡neutrophils

Neutrophils are white blood cells that are the immune system's aggressive first responders to infections. The video refers to them as "crazy aggressive chimps" that can cause damage to healthy tissue during their explosive defense mechanisms.

💡cytokine storm

A cytokine storm is the flooding of the body with inflammatory cytokines during an infection leading to widespread inflammation. The video depicts cytokines signaling as air raid sirens, warning of an exaggerated response.

💡autoimmunity

Autoimmunity is when the immune system mounts a response against the body's own healthy cells instead of external pathogens. This can lead to chronic illness. The video hints that there is a fragile balance between immune-mediated damage and fighting infection.

Highlights

When you get sick, your body activates sickness behavior and reorganizes your priorities to defense.

Properly activating your immune system is intensely disruptive and draining.

If you are old or weak, keeping your immune responses going can overwhelm your capacities.

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

As you survive diseases, the functionality of your organs may decrease.

Getting sick is a gamble with your health on the line.

When you survive a disease, you gain memory cells that protect you from future infections.

Vaccines train your immune system without the damage of real infections.

Vaccine side effects are generally mild, while diseases can leave permanent damage.

Immunity from vaccines is often better than natural resistance.

Vaccination helps train your defenses to be ready when diseases arrive.

Humanity's progress may eventually overcome disease.

Climate change is a main challenge needing cooperative action.

Offsetting carbon emissions can make a real climate difference.

Old refrigerators release extremely potent warming gases when they leak.

Transcripts

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

That surviving a disease leaves you better off.

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

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

situation in the future.

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

So, what happens when you get sick?

The Machinery of War

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

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

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

to the presence of enemies.

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

fast.

Let us start an invasion and see what happens.

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

proteins called cytokines.

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

release many more cytokines, amplifying the alarm.

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

Mobilization is under way.

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

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

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

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

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

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

your immune system is intensely disruptive and draining.

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

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

weapons.

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

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

calories to maintain.

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

to the enemy infecting you.

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

to construct.

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

a minefield inside your blood.

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

Usually you acquire your resources by eating.

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

you can’t spare.

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

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

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

better.

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

too draining.

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

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

responses going can overwhelm your capacities.

Your Immune System is a Jerk.

Our enemies too.

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

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

damage caused by immune cells.

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

guns.

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

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

example by smoking.

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

can cause significant damage and cell death.

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

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

body rushes to close them.

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

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

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

gooey tissue structural integrity.

You have seen the result on your skin as scars.

A scar is different from the original tissue.

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

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

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

A scar on the lungs no longer captures oxygen.

A scar on your liver makes it a worse filter.

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

functionality of your organs may decrease.

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

permanent.

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

damage and train your immune system!

The best way to train your Immune System

Your immune system is unique.

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

weaker against others.

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

infection.

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

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

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

resistant against Ebola.

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

Where you are on this spectrum is impossible to predict.

And you also respond differently to every possible infection.

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

it was more like a mild flu.

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

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

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

Always.

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

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

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

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

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

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

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

ever shows up for real.

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

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

Nature Vs Vaccine Dojo

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

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

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

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

No scars, no permanent damage.

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

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

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

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

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

Nature dojo is just way more risky.

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

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

way.

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

them to.

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

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

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

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

we may overcome disease for good.

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

your older self will be grateful to you.

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

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

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

videos.

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

down to the individual.

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

who help you offset your carbon emissions.

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

footprint is.

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

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