All About Allergies

By Adem Lewis / in , , , , , , , , , , , , , , , , , , , , , , , , , , /

For most of us, springtime means sunshine,
green grass, and blooming flowers. But for some, it can also mean sneezing and
watery eyes, or even trouble breathing. We’re talking about allergies, and almost
anything can cause them: grass, flowers, ragweed, peanuts, bee stings, penicillin, soy, latex,
… the list goes on and on. An estimated 40 percent of the world’s population
suffers from allergies, and that number is on the rise. But how can a peanut, so small and simple
and delicious be so deadly? And what even ARE allergies, anyway? How are
they caused? Can they be prevented, or even cured? Well, to understand allergies, we first need
to talk about your immune system. Your immune system is meant to keep you healthy,
but in people with allergies, they tend to overreact. And you can lay the blame on your lymphocytes,
or white blood cells. Lymphocytes are like little hall monitors,
traveling around your body on the lookout for antigens — foreign invaders like parasites,
bacteria and viruses. When a lymphocyte detects an antigen, it begins
producing large, y-shaped proteins called antibodies. Humans have almost ten billion different kinds
of antibodies, and each one binds to a specific antigen, neutralizing the threat. It’s like
having the keys to ten billion different locks. But in an allergic person’s immune system,
the lymphocytes get confused. They treat allergens like they’re antigens. Allergens themselves are really just a kind
of enzyme, called an antigenic protein. Scientists don’t know what it is about the
structure of these proteins that causes such alarm in some people’s immune systems. They
don’t resemble viruses or bacteria, but the immune system still treats them like a
threat. But doctors do know that while thousands of
substances can be allergens, some are much more likely to send your immune system into
overdrive. That’s why just eight foods account for
90% of all food allergies —- tree nuts, eggs, soy, peanuts, fish, shellfish, milk,
and wheat. When someone’s first exposed to an allergen,
their lymphocytes create a bunch of antibodies called immunoglobulin E, or IgE. Everybody has IgEs. And when they attach to
the surface of certain immune cells, those cells then release enzymes that help fight
infections. It’s all part of a defense system that evolved
to protect us from parasitic worms and bacteria, and it’s pretty effective. At least, when
it’s working properly. But when an allergic person’s lymphocytes
are faced with an allergen, their immune cells freak out and overproduce these enzymes, causing
the symptoms of an allergic reaction. These can include a runny nose, itching, or
hives — localized swelling on the skin. More severe reactions can involve nausea, vomiting,
or even trouble breathing. The severity of these reactions is dictated
by a wide variety of factors, like how much of an allergen is in the body, and how concentrated
the immune cells are that have IgE’s bound to them, and how much of the enzymes they’re
producing. In some people, the histamine enzyme can be
the problem. Histamine dilates blood vessels and increases
mucus production, allowing infection-fighting cells to travel to an affected area. Too much
of it can cause itching or a runny nose. But immune cells in other people might release
a lot of an enzyme called tryptase, which is linked to the absolute worst reaction you
can have… anaphylactic shock. An overload of histamine and tryptase can
cause your blood pressure to plummet. Then the bronchial tubes constrict, making it harder
to breathe… and in some cases, the throat can swell, too, cutting off the oxygen supply
completely. Hundreds of people in the US die every year
from anaphylactic shock. Which is why those who have severe allergies usually carry an
epinephrine shot, just in case. Epinephrine is a form of adrenaline. When
it’s injected, it constricts the blood vessels and eases swelling, allowing the sufferer
to, hopefully, breathe again. The effects only last about twenty minutes,
though, so the person will usually get themselves to a doctor. So that’s how allergies work. But why do
we have allergies in the first place?! I mean, how does it make sense that something
totally harmless to one person can be lethal to another? Well, it doesn’t make any sense, at least
not yet. Scientists can’t quite agree why we have allergies. They do know that allergies have a genetic
component. Studies have shown that if you suffer from
allergies, there’s a 33 percent chance that your kid will develop allergies as well. And
if both parents have allergies, that risk jumps to 70 percent. But it’s not that the child inherits specific
allergies. They’re just more likely to develop them. So a parent who has an allergy to eggs
could have a kid who isn’t allergic to eggs, but is allergic to peanuts. Kids can outgrow their allergies, though.
The extra IgEs that their bodies produce are at their highest levels before the age of
10, but they can drop drastically by the time they reach 30. And if someone has an allergy to one antigenic
protein, there’s a good chance they’re allergic to other proteins, as well. That’s
called cross-reactivity. So if you’re allergic to ragweed pollen,
you’re more likely to be allergic to apples, because the protein structure in both are
very similar. That’s why the immune system treats them as the same antigen. Why certain people develop allergies isn’t
the only thing puzzling scientists, though. Allergies around the world have been rising
since the early 1980s. Reports of food allergies among children in the US, for example, increased
by 20 percent from 1997 to 2007. Some scientists suggest that air pollution
might be to blame. Three studies in the early 1990s linked pollutants
like sulfur dioxide and carbon monoxide to allergic asthma, which can cause shortness
of breath and wheezing. In one series of studies, researchers found
lower instances of allergies among children in what was then East Germany, compared to
those who grew up in the more developed West Germany. Even though the kids in East Germany were
exposed to a lot more air pollution than those living in the West, scientists concluded that
the Western pollution contained more carbon monoxide from automobile exhaust. But there are other theories, too — like
the idea first developed in 1989 known as microbial deprivation. This model essentially suggested that the
modern, industrialized world is just too dang clean. We know that allergies are highest among those
who live in wealthy, developed countries and in urban areas, regardless of race or sex. According to microbial deprivation, children
who grow up in these environments simply aren’t subjected to enough dirt, grime, bacteria,
and parasites… depriving them of what scientists call benign exposure. The hypothesis suggests that this benign exposure
helps balance the immune system, giving it something to fight. Maybe when there aren’t
enough pathogens to keep it busy, it overreacts and attacks harmless things like pollen, instead. There is some research to back this up, too. In 1998, one study suggested that children
who went to daycare, and thus were exposed to lots of viruses, had lower instances of
allergies than those who didn’t go to daycare. And in 1999, a Swedish scientist noted that
farmers’ children who had regular contact with animals before the age of 7 and drank
unpasteurized milk, didn’t develop as many allergies as children who lived in the city. Now, these scientists aren’t suggesting
we return to the days of dirty drinking water, because a lot of those parasites and bacteria,
like dysentery, killed people. 200 years of sanitation have brought a lot
of good to the world. But researchers are noticing a correlation
between an environment devoid of microbes, and an increase in allergies. This link has led to an experimental form
of treatment called Helminth Therapy. Helminths are parasitic worms, like hookworms,
that people deliberately infest themselves with in order to ease their allergies. Sounds
kinda gross, right? But recent studies are showing that it might
actually work. For instance, a study in 2012 found that patients
infected with worms needed less medication that those who were worm-free. The down-side
is, those worms also gave the patients stomach aches, bad gas, and diarrhea. Yeah… I mean, parasitic worms will do that
to you. Thankfully, there are ways around allergies
that are slightly less horrifying. For example, in many cases, we actually know
which antigenic proteins are causing the reaction, so we can get around them. Like when it comes to eggs, we know they have
four different antigenic proteins in the whites alone, plus three more in the yolk. Meaning that someone whose immune system reacts
to the antigenic protein in the white could be perfectly fine eating the yolk. And, some of these proteins, specifically
those in eggs and milk, can be destroyed by extensive and prolonged heat. One study showed that only 4 percent of children
with an egg allergy reacted to a muffin after it was cooked for 30 minutes at 175 degrees
celsius. Heating the proteins had changed them enough that they weren’t triggers anymore. And then there are the more traditional forms
of allergy treatments, like immunotherapy, which works by changing the way your body
responds to allergens. Once or twice a week, over the course of a
year, a patient is injected with tiny doses of an allergen. Because the exposure is so
low and so constant, the immune system gradually stops responding with IgE antibodies. Instead, it begins responding with IgG antibodies,
another, more common type of antibody that fights chronic infections. These IgGs don’t bind with immune cells
first, so they don’t release histamines or other chemicals that cause an allergic
reaction. Instead, they bind to an antigen and neutralize
it directly. The downside of these shots is that they’re
really expensive, time-consuming, and don’t work on severe allergies, which can be triggered
by even those small doses. To treat more severe allergies, researchers
are looking into anti-IgE immunotherapy, which directly blocks the production of IgE and
just takes the whole thing out of the equation. In this kind of treatment, patients are given
shots of a drug called omalizumab, which binds to existing IgEs in the blood, rendering them
useless. It also blocks future production of the antibody by binding to the lymphocytes
that make it. But then guess what! Some people — although
really, very few — are allergic to omalizumab! So the safest option, at least for people
with food allergies? An avoidance diet, which is the official name for what the rest of
us would call common sense: just don’t eat what you’re allergic to. So if you’re allergic to shellfish, skip
the lobster. Boom. Problem solved. Thanks for watching this episode of SciShow,
which was made possible by our latest President of Space Conner Tart, who was nominated for
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100 thoughts on “All About Allergies

  1. Avoiding things you are allergic to is nice and easy, when you are only affected by eating things, not so easy with pollen. I'm not allergic to pollen, just various vegetables, handy being vegetarian. Unfortunately the reaction is not just caused by eating them. I can't touch them, which is still easy to avoid, but I also get a reaction from breathing near them. Easy enough to avoid at home, but when I'm walking along the street and can smell onions cooking, I know that I might have difficulty breathing soon. This is coupled with not necessarily knowing where the smell is coming from or which direction to walk in to get away from it. Fortunately my reaction is less severe outside, where the concentration of allergens in the air is obviously lower than if I was in a kitchen where onions are cooking, either way it's quite annoying.

  2. I have what I've nicknamed gradual allergies. I used to be able to eat nuts like walnut and peanuts, but now if I get peanut dust in my nose, it itches and burns at the same time. FML😑

  3. *Allergies

    Immune system: Red alert we have intruders!!!

    Pollen: no we just got lost and ended up here.

    Immune system: No excuses! you are a harm to this body!

    Pollen: But im just a piece of pollen i just got blew here.

    Immune system: LOAD THE TANKS!

    Pollen: Wait!

    Immune system: FIRE!!!

    Me:… *Sneeze

  4. As so as I could walk I would steal the Nutella and hide in a cupboard and fuck that shit up. I would eat the whole thing. One day when I was doing my usual spoon and Nutella session I had an allergic reaction out of the blue. I am now allergic to almost every nut you can think of and haven't eaten Nutella since. 🙁

  5. I get hives from lavender scented dryer sheets and lavender body wash. Don't think I've really heard of anyone with that allergy before. At least they aren't bad, I've hated the scent anyways but they kept using it anyways until I started itching Luke crazy

  6. I'm currently going through the immunotherapy shots for bad allergies to airborne pollens, some grasses, and some animal dander. They give you a shot twice a week for 4 months, building up the dose until you reach a maximum dose (called the maintenance dose). Once you reach the maintenance dose, you get the shot once per MONTH, but the treatment can take 3-5 years optimistically. The shots are covered 80% by my medical coverage, which is good because the shots are $300 per vial. The vial lasts about a year. Before the shots, I had environmentally triggered asthma caused by allergies to floating spores in the air. I would wake myself up at night gasping for air, and I would have to sit upright and catch my breath. I lost out on a LOT of sleep. I couldn't workout or do anything too physical because anytime I would breathe heavily, something would trigger my symptoms. It's now almost been 3 years of getting the shots. I never wake up gasping for air anymore, I can workout and go running. I occasionally still need the puffer if I, say, go for a hike in the woods, but the shots have really helped. They're expensive, but they're well worth the improvements you'll see.

  7. I feel you I have indoor and outdoor allergies I would burst into hive at random times allergic rhinitis also allergic to silver…. and ppl tend to buy my silver jewelry -.- but no food allergies that I know yet 🙁

  8. what about lactose intolerant. i know my body hates dairy in any form. Would that be considered being allergic to milk?

  9. Just one thing not really correct: Immunotherapy work for severe allergie, it just won't make theallergie go away, but it can make it way less severe.
    For example, I was allergic to eggs. (10^-12grammes, wich made me unable to eat even chicken). But after years of immunotherapy, I am now able to eat cooked eggs. Uncooked or badly cooked will still trigger some response, but I still won't die and I can go on in my life. (but I have to eat some lysozyme or the allergie will come back)
    So… yeah, not perfect, but it still really usefull for people with extreme allergie.

  10. I have an mild allergy to an ingredient found in some sea food dishes which causes a bit of itching in and around my mouth for a few minutes
    I have no clue what it is
    I also tend to get a runny nose at random times during the year that doesn't seem to correspond to seasonal changes or other things

  11. so why dont we find out what our immune systems like about the worms, isolate them, and take them like medicine… its 2017, i shouldnt have to chose between itchy eyes and diarrhea- figure this shit out science!

  12. Well my Grammy is bipolar and Gran dad worked as enginer. My mom told Grammy had strict expectency of cleaness, and didn't like feeling like a slob for their maid. Had my aunt and mom clean before the maid came. I'm saying this I'm connecting what you to my Aunt's allergy for silver and mom's for gold is from cleaning so much. Also my make up is supposedly be allergic to make up. I never wore make up since I was a kid so I'm not sure if I really am or just had a bad first taste to make up.

  13. Many things can trigger an allergic reaction. It happens when your body's defenses attack something that's usually harmless, such as pollen, animal dander, or food. The reaction can range from mild and annoying to sudden and life-threatening
    I made a video in my channel about 8 Common Allergy Triggers you must know…you can watch it

  14. I have horrible allergies! I just posted a video about what helped me! I finally don't get sinus infections every month!

  15. hey sci show do show about the see through rats and mice using uDISCO is super cool. also do show on our suns solid surface . you guys rock

  16. Growing up I was allergic to absolutely nothing. After I had my daughter, BOOM! Seasonal allergies every spring. Itchy/watery eyes, runny nose, sneezing… It sucks. They seem to be fairly easily controlled with antihistamines and nasal decongestants luckily. I'd be really interested in learning more about how allergies develop during/after pregnancy.

  17. I will never play the game king of Avalon or lords avail, so advertisers you are WASTING your money showing them to me: posting this comment because by doing this I control the ads I am shown, try it. With this method we will take down youtubes money machine, also if ads play anyway close your eyes and plug your ears but let the, play. This way we will cost YouTube billions.

  18. Anyone noticed that the thumbnail for this video is the same as seeker's "why do we get allergies" video?

  19. People in rich areas have money to treat allergies so those people survive, while people in poor areas die… It's called natural selection…

  20. You know I can understand the body getting confused and causing an allergic reaction. What I don't understand is why it sometimes then kills the body it's trying to protect. You had one job.

  21. Is Michael's beards slightly off center? I noticed it, and now I can't stop staring at his chin….. 🤔

  22. Allergic to mold, sunlight, dairy, egg yolks, most meats (basically all except seafood), and cats. (Plus I'm sensitive to heat…Like, I'll get heat rashes..)
    Sadly, my room has mold, gets way too hot, and I have two cats. I also can't avoid sunlight, because I have to walk my dog during the day. I also can't avoid heat, or my cats. Unless anyone knows how to keep an apartment below 50°F, without making the other occupants feel cold. I also can't get rid of my cats, as they belong to my mom and younger brother. And no, I can't move out either, as I have no way of supporting myself.

  23. Here's a weird one for you, I'm allergic to pork, no bacon or it's praying to the porcelain god, hives, cramps, etc. (also yes I have gone for testing)

  24. And then you are allergic to cold so – what? Should I avoid going outside for half of a year?
    I learned how to deal with food allergies years go, those are not even a problem. I deal with spring allergies and allergy to dust just fine. Cold though? Apparently not really treatable and torturous.

  25. IT'S. THE. FOOD. The common thing between all the possible causes named is bad food. Rich people eat the worst food! Processed foods, refined carbs/sugars, dairy, and excess meat! Older cultures eat a diversity of species— veggies, fruits, legumes, mushrooms, grains, etc. When people adopt a whole food plant-based diet, third allergies disappear. It's no mystery my friends, look it up.

  26. See how many YouTube scientists we have. How is my mother allergic to shrimp but not other shellfish such as lobster and king crab?

  27. If a bullet is traveling at 1000 feet per second, and a camera captures a 1 square foot area at 100 frames per second, what are the chances the camera will capture the bullet in a frame?

  28. I'm allergic to large amounts of pollen, Aspartame (found in many chewing gums and diet drinks among other things), and cats (mostly their fur). I've minimized the reaction to cats (kinda had to because my fiance has a cat) by taking allergy pills every morning and long interactions with the cat. Eventually I didn't have to take the medicine as often and then the reaction was gone… For adult cats. Still working on the kitten fur allergy. The others are either only bothersome when it's in a large dose or I can completely avoid it.

  29. Just a tip for those suffering allergies: your mattress is full of nasties (e.g. dustmites, bedbugs, mold) which can trigger your allergies. I recommend getting an organic mattresses (i got a natural latex mattress) and it has improved my sleep and health immensely.

  30. I have alllergies to dust and they improved at 30 until I got bad news that bothered me. I now have severe allergies. I lose my voice 5 times a year sometimes 6. Changing meds hasn't work. I am looking at removing more of my textiles. I am also trying to deal with the news as it impacts my future. Just thought I'd warn you just how bad stress affects these. I used to be on one medicine a day now I'm on three.

  31. Thare is more than just shots that can help for small allergies cat and dog allergies are being treated not really treated but getting better right now I can see by drops I put under my tongue at night away and I've actually even seen that it's going away but it doesn't work affect my peanut and tree nut allergy that has high chance to kill me.

  32. Have you tried morphogenic field states to cure allergies? Morphogenic field states can fix literally anything if you have the correct field. There are fields embedded in audios in Youtube available for free, for a variety of issues. I cured ulcer using fields from channel called "Sapien Medicine". (they are the only channel out there for morphic fields). They do not have an audio to fix allergies yet; I have been requesting them for months… They'll make it if many people request. Will you guys request too? Latest requests are beneath their latest video. Just like and reply to existing allergy cure requests if you plan to. Their vids work. You can browse their existing vids and if you can find something else for you, and check for yourself. They have vids for burning fat, shrinking stomach, 20/20 vision, etc.

  33. The only thing i want to know, i can't seem to find any information on. I see warnings on all sorts of products, foods, tea, oils, medicine, that says not to use frequently or an allergy or sensitivity will occur. So supposedly if i drink chamomile tea everyday i will become allergic to it. The warning exists but i can't find any information discussing this or why such a thing would occur? How is it possible for overuse to result in allergy and how frequently does this actually occur?

  34. I have a friend who is allergic to: Tree nuts, gorund nuts, eggs, shellfish, lamb, beef, pork, pollen, some fruit i cant remember. Like damn dude just a glance at my lunch is enough to kill you 7 times.

  35. This is me I am allergic to peanuts. And many more… like birch, dandelions, cats. I sneeze and my eyes itch ugh! And people at my school don’t know what are allergies so they don’t believe me😖 when I eat too many peanuts I have anaphylactic shock so I always carry an epipen with me. ALLERGIES ARE THE WORST! My number one wish is that I could be cured from allergies😔.

  36. My family has a strong genetic history with allergies. My mom and my brother both have allergies and food intolerances. My brother also has asthma. I may have mild allergies, too. My family relies on the knowledge and advice of medical experts to help us cope with allergies and asthma.
    I have an important question: Is it possible that a person could develop allergies in their thirties?

  37. So I have this cat who's been with me since I was a baby. One day, my Mom got me two new kittens. But we had to give them up. Why? Because I had an allergy to them. At the time, I didn't have an allergy to any other cats. Just those two kittens.

    I also had a bee allergy but after years of not getting stung, I was no longer allergic. And then I got a gluten allergy. Despite eating gluten my whole life…

    Just…. Why?

  38. My only allergy must be some kind of twisted cosmic joke. I’m allergic to Claritin, a common allergy medication

  39. best purifier for mold and dust removal in the home call 800 number for discount

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