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What do we have here oh no no those are cashews. So is this like a bowl full of
death to you? Yes, well cashews aren’t as strong of a reaction for me but I am
allergic to tree nuts. It’s not fun, it’s not fun at all. Hey smart people, Joe here.
I recently invited my friend wheezy waiter to come by and talk about food
allergies. Just one, they’re not real cashews, they’re stunt cashews. Of course
you should never trick a friend with the food that they’re allergic to, but it’s
okay wheezy waiter and I are friends, and I’m
a doctor. These days most of us know someone with a food allergy, some food
they have to avoid eating, or even coming into contact with in order to avoid a
dangerous reaction or even death. But why are people allergic to food? And why are
food allergies on the rise? It’s nuts. Maybe I’m just getting old but
it seems like food allergies are more common than they used to be. Well we’re
not imagining things, scientific data backs that up. The
percentage of children with food allergy has definitely increased in recent years.
I’m allergic to all tree nuts so I’m allergic to walnuts, pine nuts, almonds,
cashews, hazelnuts, macadamia nuts, pistachios – here in Texas – pecans
everywhere. Not pecans no pecans I always say pecans, but you’ve taught me it’s
pecans. Yeah I play the right way yeah. That stuff ends up in a lot of different
foods, so I imagine you have to have accidentally encountered this stuff before.
I have accidentally encountered almost all those that I listed. What happens is my mouth swells up, my throat swells up, I get hives, I get hives
in my lungs, I can’t breathe, horrible stomachache, and it lasts for
three hours. But I don’t think about reading labels and that’s a whole
difference about how we navigate the world as things that I don’t have to
think about and you do. And especially now it seems like the nuts are cropping
up in everything like barbecue sauce or cocktails, like drinks now like to have
walnut bitters in them. To make matters even more confusing, adults can also
become allergic to foods that they never had issues with as children. I’m Emily
Graslie I am the host and creator of the YouTube
channel The Brain Scoop and I work for the Field Museum as their Chief
Curiosity Correspondent. So I saw on Twitter recently that you aren’t getting
along with certain kinds of nuts very well anymore. Yeah I’ve never had a
problem really with any sort of food you know, but otherwise never have had
any sort of allergy whatsoever then a weird thing happened. Why don’t we try
almond milk for the first time? I never tried it. The next morning just routine
morning on my way to work I had my bowl of cereal, poured the almond milk on it
and I got to work and I noticed that my nose was just dripping like a
faucet, and I realized I was hot and itchy, and I noticed that I was just
absolutely covered in full-body hives. I just was like this is really weird.
Now a true food allergy is different from a food intolerance. This is really
important like if you’re lactose intolerant and you can’t digest cow’s
milk. It can make you feel really sick Aches, pains and digestive troubles, that
kind of stuff. But if you’re allergic to milk, it could kill you. A true allergy
is when your body’s immune system has a reaction to the food on a molecular
level. It’s your body treating food as a germ or an invader, which actually
doesn’t make sense. Let’s look at how this works. Food is made up of lots of
different molecular bits like the fats, carbohydrates, and proteins. We’re gonna
focus in on the proteins – everything we eat has proteins and they come in a
variety of shapes. Our bodies usually digest food proteins down to their most
basic units, but some food proteins don’t get completely broken down and they
escape into the body where they meet the immune system. Now it’s your immune system’s job to recognize protein shapes that come from dangerous invaders – viruses,
bacteria, things like that sneaking around your body. But peanut butter
should not cause this reaction. This makes no sense. Cobras, jellyfish, really big wasps. Maybe. But not deliciously roasted
legumes. Molecules called antibodies stick to the foreign food molecule
leading to the release of a chemical called histamine. Which makes you really
itchy, or if the reaction is bad enough, it can cause anaphylaxis – where the
entire body just goes haywire. From dizziness to swelling to your ability to
breathe. So I started looking up like can you just develop an almond allergy or a tree nut allergy as an adult – you can and I said
well what could cause it. The only unusual thing was this almond milk, so I
immediately made an appointment with an allergist. We needed to determine if
almonds had specifically caused this allergic reaction. So honestly we did
this food challenge and nothing happened. Nothing happened so you’re sitting there
now and you still have no idea what triggered this, what it really was, or
what you might meet again that could give you a problem. And it could be
nothing, it could be something else that I ate. Emily had an allergic reaction to
something. In cases like these even doctors can be stumped. In the meantime
he told me when I left the office that day that I needed to operate as though I
had a life-threatening tree nut allergy. So he prescribed me epinephrine and
I have an epinephrine injector that I have to carry with me everywhere. I
have to spend the next year carrying this around with me, and maybe have to use it on some mystery food that we don’t know. I keep coming
back to one basic question, why would our bodies bother to have such extreme
reactions? Reactions that could kill us after a handful of trail mix, or a glass
of milk. The truth is we don’t know why food allergies exist – there is a leading
theory and I should stress this is just a theory, that allergies might
exist thanks to parasites. The part of our immune system that recognizes
allergy causing food also reacts to certain wormy, buggy infections.
Humans are a lot cleaner than we used to be, back before hand sanitizer and indoor
plumbing, and you know, science. Today we don’t have as many parasites entering
our bodies, so maybe that bit of our immune system is just bored –
so it’s overreacting and attacking foreign-looking proteins in our food
instead. Our clean, sterile, no dirt eating lifestyles could be behind the rise in
allergies of all kinds. But that’s just a theory, a parasite… wait that’s not my catchphrase What am i doing? Peanut allergies are the most common food allergy, affecting nearly 1 in 40 kids in
the US. In all, we know of at least 400 proteins for more than a hundred and
seventy foods that cause allergic reactions with eight foods
accounting for 90% of those. Now a lot of people are allergic to shrimp and other
shellfish, and a lot of those people are also allergic to little bugs called dust
mites. Now shrimp shellfish and dust mites are all invertebrates and all of
them trigger allergies thanks to a protein called tropomyosin. Well they
share that protein and it’s very different from anything our bodies make.
This is an example of cross reactivity, like if you’re allergic to cashews you
might also be allergic to pistachios or mangos since they’re all in the same
plant family. I’m telling you evolution explains everything. So how can you avoid
food allergies for you or your kids? Well, just a decade or two ago doctors
recommended not giving young kids foods that commonly trigger allergies for at
least the first few years of their life. But that was actually the exact wrong
advice. Food allergy rates continued to rise, so doctors changed their
recommendations. Today’s advice suggests parents should slowly introduce common
allergic foods early, and in small amounts – and it seems like it’s working.
Food allergy rates have stopped rising at least. I mean we’re parents now mm-hmm
How does your having an allergy affect what you’re introducing your chile
– if it were up to me I probably would be incredibly more wimpy about it,
but my wife my wife is introducing all these things. She introduced all the all the nuts to her so far and she’s not allergic.
So yeah, and I got nervous every time. Which is fine.
If you already have a food allergy, unfortunately there’s no cure. We’re
developing treatments like getting the immune system accustomed to allergy
causing foods in small doses, there’s even a sticker that acts almost like a
nicotine patch for peanut allergy. But please remember always talk to a doctor
before you attempt any treatment. Sadly with food allergies there’s still more questions than there are answers. We know what’s causing them, we know a little bit about how to prevent them, but we don’t know why they
exist or how to cure them. It’s really stressful to not know what caused it
and to not have any reliable way of testing what caused it. You take for
granted when you don’t have a food allergy – you can go wherever you want
ready to eat anything and so you’re automatically your world like shrinks
quite a bit. Every restaurant you go to, every lunch that you eat, if you didn’t
prepare it yourself I’m wondering like is this gonna have something in it that
could kill me? And am I allergic to almonds? And if it’s not almonds then what is it?
Are people taking me seriously. That’s a big concern that people who have food
allergies. But, it can be life-threatening.
Is it frustrating that people can’t give you an answer about why this happened.
Yes, yes I would love a cure that would be great. Do you’ve a cure are you gonna introduce? A cure, well it’s called exposure therapy.
But every scientific question that we know the answer to today was once a
mystery just like this an answer barely out of reach, in the fog of not knowing
yet. Someday we’ll figure it out. Some nuts
are just tougher to crack than others. Stay curious.