if you're a fan of our work you probably value rigor and humility in research and are willing to change your mind based on new information you might also appreciate the same principles applied to important questions like how can my donation make the biggest impact give well this video sponsor does precisely that they publish all of their footnoted research along with their past mistakes for free more details including how to get your donation matched at the end of this video an allergy is like finding a spider in your bedroom and exploding a nuclear bomb sure spiders
are upsetting and now dead but so are all of your neighbors and your dog you can be allergic to an incredibly diverse and weird amount of stuff pollen dust insect stings animal hair any kind of food latex and even your own sweat what of the wildest things about allergies is how fast they are breaking out suddenly and violently and you can develop new allergies one moment you're enjoying a shellfish you ate thousands of times before and the next moment you wake up in an ambulance a shrimp can kill you how bizarre but like what are
allergies why do our bodies flip the table on harmless stuff there's a wild and interesting idea we want to share with you humans might have created allergies by accident by getting rid of worms this is very upsetting and interesting for your ancestors being infected Ed by worms was a reality of life we won't get into the disgusting details but in a world where drinking water and our poo were close buddies some species of worms found just the perfect cycle of Life they enter your bodies with the water and make themselves at home sometimes for decades
and then release their eggs or lvi with your poo which used to go back to the water we drank so until recently in evolutionary terms our ancestors had to deal with frequent or permanent worm infections this caused all kinds of unpleasant health effects our immune systems had to find weapons to get rid of them but how do you do that from the perspective of a cell worms are Citys scale kaijus reaching Beyond the Horizon worse instead of skin parasitic worms have an elastic protective layer that withstands even stomach acid you really need to pack some
punch to cause damage it takes an army to kill a worm we're simplifying but basically when a worm ENT your body for the first time intelligence cells notice their presence they move to your lymph nodes and activate specialized antibody factories called B cells we explain them in detail in this video These B cells are told that they need to fight parasites and start producing a special class of weapons IG antibodies tiny protein crabs with two pinches that connect to worms like magnets to metal IG floods your entire body and basically begin arming a nuclear bomb
an army of really scary cells called mast cells mast cells are huge bloated fellows filled to the brink with histamine and other nasty chemicals they pick up the IG floating around and cover themselves with them like Angry Hedgehog grenades without their safety pins and then they just lie and wait angrily so now you have millions of bombs in your skin lungs or gut until the day the M cells meet a worm trying to enter your body there's not much time to get rid of it so things escalate rapidly the mast cells with their IG spikes
grab onto the worm particles and kind of explode they release all of their dangerous chemicals all at once a few things now happen in Rapid succession first some of the Mast Cell chemicals wound the worms ripping wounds into them and making them really unhappy then emergency chemicals like histamine cause massive and Rapid inflammation ordering your blood vessels to flood the battlefield with water to flush the worms out they also order your cells that make mucus to go into overdrive and cover the worms in sticky slime other chemicals are like Aid Sirens screaming loudly throughout your
body for anti-parasite soldiers eosinophils first thousands then hundreds of thousands hear the alarm and leave your blood vessels to where the M cells are causing inflammation not only do they make the inflammation worse they carry extremely toxic chemicals that they vomit at the worm ripping open its defensive layer and causing horrible injuries sometimes this will straight up kill the parasite lastly the anti-worm coordination cell arrives the basail it makes sure that the immune system doesn't slow down but keeps attacking with violence it keeps the inflammation going and alerts more and more attack cells to the
sight of battle zooming out we see that the chemicals from your antiparasite forces make your smooth muscles contract rapidly pushing everything that's inside outside your intestines combined with all the water you notice this as diarrhea as your body tries to expel the stressed parasite in your respiratory tract loads of mucus and water flood outside trying to take the worm with them if this happens under your skin your tissue is red hot and itchy as your immune system is trying to commit murder it takes a fierce Army to kill a worm and your antiparasite forces have
the license to act rapidly and with intense violence okay this is nice and all but what does all this have to do with killer shrimps what is an allergy parasitic worms don't love being ripped apart by millions of bombs and as all living things do they adapted to the deadly attacks on them in a nutshell worms release a plethora of chemicals to manipulate your immune system they make it weaker and much less angry like immune system wheat which is pretty bad for your survival because you have to fight off all sorts of intruders every day
our ancestors were B basically unable to prevent regular worm infections so as the worms adapted to us our bodies had to adapt to them to balance out any weakening worm chemicals one adaptation might have been to make our immune system more aggressive so it could still defend against other Invaders and then a hot second ago in evolutionary terms everything changed we suddenly invented soap and hygiene but most importantly the separation of poop and drinking water this destroyed the life cycles of parasitic worms and the ones that remained were eradicated by modern medicine worms still infect
up to 2 billion people mostly in undeveloped rural regions or slums with unsanitary conditions and dirty water the people who escaped these conditions now face an interesting problem an immune system without a major enemy that had kept it down for millions of years it could very well be that our immune system still operates assuming that worms are making it weaker and that it has to be overly aggressive because of that and while IG mast cells basophils and eosinophils also have other jobs a major reason for their existence has now gone away but they kind of
act as if worms are around only that they now attack other dangerous foes like shrimps this is exactly what happens when you have an allergic reaction to a shrimp your immune system picks up shrimp proteins and produces IG antibodies against shrimps the antibodies then are mast cells turning them into bombs so you have millions of bombs in your skin your lungs or your gut with a license to choose violence even when provoked a little bit until one day you eat another shrimp your anti-parasite forces flip on like a switch only there is no K you
to attack this is what you experience when you have an allergic reaction extremely powerful weapons now Target your own body under your skin your blood vessels suddenly turn leaky fluid streams into your tissue your skin swells up and turns red often in itchy hives you immediately feel hot and unwell in your digestive system the mast cells can cause nausea cramps and sharp pain as water floods into your intestines and triggers intense diarrhea and vomiting your respiratory tract swells up making breathing hard way more dangerously histamine and other chemicals can cause the smooth muscles in your
lungs to tense up in the best case you get a stuffy nose in the worst case your sub fighting for your life mast cells all over your body unload their Bombs all at once causing an anaphylactic shock your blood loses so much water that your blood pressure drops to dangerous levels this alone is life-threatening in commodation with the things going on in your lungs anaphylaxis is a life or death emergency often with just a small time window to do anything about it allergic reactions truly are no joke even the deadliest diseases like Ebola need Days
to Kill you but your immune system can kill you within a few minutes and this is why a shrimp can kill you because on a fundamental level an ingenious defense system vital for our species survival for millions of years is fighting imaginary kaijus yet we still don't know why some people produce a lot of IG antibodies against certain substances and others don't we don't know why some adults develop new allergies later in life or why some allergies disappear over time and we're not sure or if the lack of worms is the main culprit only that
the cells that evolve to fight them are responsible for the symptoms of allergies there are other ideas like less diverse microbiomes or increased pollution maybe it's just a combination of all of them but what we clearly see is that allergies and their more serious cousin autoimmune diseases have been rising massively in the last 100 years wherever humans moved into more sanitary conditions and got rid of some of the horrible parasites hunting us hopefully we'll figure it out and prevent allergies forever because one thing's for sure we don't want to get worms back that would really
be like finding a spider and exploding a nuclear bomb givewell wants as many donors as possible to make informed decisions about high impact giving they have now spent 17 years researching philanthropic opportunities and direct funding to a few of the highest impact opportunities they found over 125,000 donors have used givewell to donate more than $2 billion rigorous evidence suggests that these donations will save over 200,000 lives and improve the lives of millions more you can find all of their research and recommendations on their site for free if you've never used givewell to donate eligible donors
can have their donation matched up to $100 before the end of the year or as long as matching funds last you can make tax deductible donations to their recommended fund funs or Charities and givewell doesn't take a cut to claim your match go to givewell dorg and pick YouTube and enter CAG to check out it took us 10 months to create this latest edition of our annual passion project the fact that we're finally able to share it with you is truly our highlight of this crazy year it's the 1225 human era calendar and it's the
best calendar we've ever made it all started back in January while we released the first video of the year we were already brainstorming ideas for the 1225 calendar for years we'd wanted to tell the story of the great journey that took our ancestors from Africa to find new homes across the planet we Dove head first into aearch we read about curious and unbelievably Brave humans who ventured out into the unknown Paving the way for future Generations but all of these incredible stories had to fit on paper on 12 Pages no less weeks of sketching and
revisions followed in February what was it like for those early Pioneers every new terrain they explored must have appeared to them like an alien planet ruled by unfamiliar climates and filled with foreign creatures meanwhile we released our next videos and in March we're finally able to tell you about starbirds the video game we're working on with TU Interactive then the calendar came to life we spent many weeks crafting epic illustrations worthy of representing 200,000 years of human history we had to get it right the adventures the hardship the incredible achievements we don't know what our
ancestors set out to find but when they settled all across the planet they laid the foundation for human civilization then in May smoking is awesome became our most successful video this year it had a huge impact and inspired many of you to quit smoking for good nothing could make us happier back in the studio we created the final piece of the calendar the cover as always we wanted to represent the entirety of the human era by adding 10,000 years to the Common Era system adding that one was the final touch and our calendar was ready
to be sent off to the printer on our YouTube channel we continue to ask the big questions like do you have free will and is AI Humanity's final invention then in September we finally held the first copy of the finished 1225 calendar in our hands we are truly happy with the result it's not just the vibrant illustrations the high quality paper or the shiny cover it's the fact that it represents such an important part of our shared human history and for us it holds all the memories of an exciting year at csk's Art we think
it's the best product we've ever made we may be a tiny bit biased but you BBS seem to love it too it's absolutely incredible to see all your comments and messages for so many of you getting the human era calendar has become a yearly tradition and a daily source of inspiration make 12,25 truly special get your piece of our shared human history and an essential part of cazar e [Music] [Music]
