
Why do we have allergies? - ph0rque
http://mosaicscience.com/story/why-do-we-have-allergies
======
ph0rque
Here's a summary if you're in a hurry:

"Why do we get allergies? No one has a firm answer, but what is arguably the
leading theory suggests that allergies are a misfiring of a defense against
parasitic worms. In the industrialized world, where such infections are rare,
this system reacts in an exaggerated fashion to harmless targets, making us
miserable in the process.

Medzhitov thinks that’s wrong. Allergies are not simply a biological blunder.
Instead, they’re an essential defense against noxious chemicals–a defence that
has served our ancestors for tens of millions of years and continues to do so
today."

~~~
LionessLover
Well... time for anecdotal sample-of-1 "science":

About two decades ago I got a _huge_ case of almost-asthma pollen allergy out
of nowhere, almost overnight. I got the usual treatment (desensitization +
meds) and it got somewhat better over the years. Simultaneously I developed
other allergies though, for example, suddenly I was _very_ allergic to cats (I
had had cats earlier, so that was new).

A few years ago I was diagnosed with a case of chronic heavy-metal poisoning.

Now, many treatments with DMPS (the main chelator for mercury) and DMSA later,
I have completely lost all allergies (and a long list of other "strange"
problems, including a real medical miracle that left the endocrinologist
repeating "I'm amazed" over and over after checking his ultrasound results
_twice_ , after asking me to lie down again because he did not trust his
results).

End of anecdote.

\------------------------------

EDIT: As someone who has taken hundreds of hours of anatomy, physiology, org.
chem, statistics (focus on public health and use in medicine), neuroscience, I
am aware that there is not "one path that explains all". There are soooooo
many pathways, and different things can affect different parts leading to
similar results. So I am NOT saying "this is the one and only way to get an
allergy". In fact it is highly unlikely that there is only one possible cause.
So if you have found an anecdote that seems to show that something else helped
and/or caused it than "heavy metals" that's just fine and normal - and has
nothing to do with _my_ anecdote. You can get a flesh wound not just by
cutting yourself with a kitchen knife, there are endless possibilities.

~~~
xenophonf
I vaguely recall reading something on Usenet or something that would have made
it onto Slashdot or Plastic in the late 90s/early 00s, where someone treated
their allergies or asthma or something by deliberately infecting themselves
with a parasitic worm---I forget which, maybe hookworm. They actually went to
so far as to cultivate the worm in some medium that they could apply to their
stomach using a custom-made patch, started pooping oocytes, and then completed
the usual treatment course for whatever it was they infected themselves with.
I can't recall if it cleared up the condition from which they were suffering,
and obviously, this wasn't any kind of controlled trial. Lord knows that such
a study would give an IRB six fits, and rightly so!

~~~
zenon
It might have been Jasper Lawrence
([https://en.wikipedia.org/wiki/Jasper_Lawrence](https://en.wikipedia.org/wiki/Jasper_Lawrence)),
who wrote about his experience on kuro5hin. I think this is the link:
[http://www.kuro5hin.org/story/2006/4/30/91945/8971](http://www.kuro5hin.org/story/2006/4/30/91945/8971),
but the site is sadly defunct now.

~~~
xenophonf
That's the one. I didn't realize Rusty put a "Disallow: *" in his robots.txt.
It made me really sad to discover that Kuro5hin wasn't spidered by the
Internet Archive.

~~~
kbenson
It was just a few weeks ago that it was posted here that Kuro5hin is dead[1].
:(

1:
[https://news.ycombinator.com/item?id=11609308](https://news.ycombinator.com/item?id=11609308)

~~~
xenophonf
Thanks. I am really, really happy to see that Rusty's alive and doing well!
And that there's a chance the site will return in static, archival-ready form.

------
Nomentatus
This isn't controversial at this point, it's becoming the consensus, and it
isn't news. But it gives me a chance to say: if you have real "allergy"
problems but test negative for histamine/IgE allergies, say on a skin test;
look into MCAS. Fair warning, your allergist may very well never have heard of
it - doctors are rarely paid to read.

MCAS = Mast Cell Activation Syndrome MCAD (Mast Cell Activation Disorder) =
MCAS or mastocytosis

Great links here:
[http://strengthflexibilityhealtheds.com/2016/02/04/diagnosin...](http://strengthflexibilityhealtheds.com/2016/02/04/diagnosing-
mast-cell-activation-syndrome-mcas-update-and-diagnosis-confirmation/)

[http://www.mastattack.org/2014/10/mcad-general-
information-p...](http://www.mastattack.org/2014/10/mcad-general-information-
public/)

[http://evilmastcells.com/](http://evilmastcells.com/)

[http://www.jacionline.org/article/S0091-6749(14)02927-3/full...](http://www.jacionline.org/article/S0091-6749\(14\)02927-3/fulltext)

Dr. Anne Maitland’s presentation on Allergies & Mast Cell Activation Syndrome
in EDS Patients.
[https://www.youtube.com/watch?v=ktFdr-9rpIM&feature=youtu.be](https://www.youtube.com/watch?v=ktFdr-9rpIM&feature=youtu.be)

[https://mastcellblog.wordpress.com/mastcellguide/](https://mastcellblog.wordpress.com/mastcellguide/)

~~~
ejstronge
Mastocytosis is exceedingly rare - an article in NEJM (one of the
authoritative medical journals) estimates that 1 in 100,000 people have been
diagnosed with the disease.

If your primary care physician has 2,000 patients (not unreasonable), s/he
could reasonably expect to never encounter the disorder outside of a textbook.

Just as in programming, doctors avoid the 'premature optimization' \- no need
to test for a rare disorder until considerably more common ones, like
allergies, are ruled out.

------
nathan_long
Skipping. I'm basically done reading controversial new medical theories and
things that "a new study suggests."

I'm not a researcher. Wait until the finding has been confirmed in lots of
studies and is Boring Standard Medical Knowledge, then tell me. Until then,
it's just going to give me the illusion of knowledge.

There's so much "MAYBE eating kelp will reduce your risk of LUPUS!" that we
lose sight of "I should really exercise more."

~~~
nkrisc
That's not at all what this is. It introduces another theory and explains the
thinking behind it. At no point does it state any sort of bunk, "do X to fix
Y."

------
chrisbennet
Here's another example of science publication/publisher's drag on science (the
paper that changed his life cost several months of his stipend):

 _" As Medzhitov searched for papers on this subject, he came across
references to a 1989 essay written by Charles Janeway, an immunologist at
Yale, titled “Approaching the Asymptote? Evolution and revolution in
immunology.” Medzhitov was intrigued and used several months’ of his stipend
to buy a reprint of the paper. It was worth the wait, because the paper
exposed him to Janeway’s theories, and those theories would change his life."_

~~~
nycticorax
That was in the early 90's, when most papers were still distributed as, well,
paper. Back then, someone had to build and run an actual printing press.

------
robertelder
Here is a fairly recent and interesting documentary on allergies:

[http://www.cbc.ca/natureofthings/episodes/the-allergy-
fix](http://www.cbc.ca/natureofthings/episodes/the-allergy-fix)

Parasitic worms, and their modulation of the immune system (and the possible
faulty human over-compensation for this) are one of a few different theories
that are put forward. I thought I would link it here because it's fairly
informative.

------
hackney
It has been stated that kids who grow up in and around forested natural areas
have better immune systems and are generally healthier for having grown up
closer to the natural earth, as opposed to growing up in an asphalt jungle.

Take poison oak for example. I have a relative whos drinking water flows
through these plants and he is now immune to it. I brought a friend to his
house (never been exposed) and after sitting on his couch, within 24 hours I
had to take them to the hospital over the poison oak which had spread to the
majority of their body. They were given a shot and we left shortly after that.

Me? I've had allergies from a young age and actually had treatments for it. I
remember laying on my stomache while the doctor pricked my back a bunch of
times. I'll still sneeze around a bunch of pollen but not enough to prevent me
from doing the work.

In short, I do not think there is a fixall, take a pill solution and that
there are many many factors to consider when treating someone for an allergy,
or anything else for that matter. My grandma was hospitalized from inhaling
bat dung, and my father also after eating some peanuts. Both could probably be
treated to be less allergic but, this would require a lengthy treatment plan
which is not a normal solution.

------
jernfrost
Ok, I scanned through quickly, but here is the conclusions as far as I can
tell.

Allergies has an important function. The problem is the severity of it. A weak
allergic reaction is what protects us from toxins, viruses etc, however for
some reason the system goes in overdrive in some people and that is not good.

It might seem like there is no significant difference between this an previous
understanding. But the significance as far as I can tell is that previously we
thought all allergic reactions no matter how small was useless and wrong by
the body. The idea was that any allergic reaction is a misfiring, while this
idea suggests it isn't firing which is the problem it is the magnitude which
is the problem.

~~~
rglullis
From TFA:

    
    
       But understanding the purpose of allergies could lead to     dramatic changes in how they’re treated. “One implication of our view is that any attempt to completely block allergic defences would be a bad idea,” he said. Instead, allergists should be learning why a minority of people turn a protective response into a hypersensitive one. “It’s the same as with pain,” said Medzhitov. “No pain at all is deadly; normal pain is good; too much pain is bad.”

------
Pyxl101
Do you know what part stood out the most to me? His difficulty getting access
to scientific papers:

> Graduate school wasn’t much better. Medzhitov arrived at Moscow State
> University just as the Soviet regime collapsed. The university was broke,
> and Medzhitov didn’t have the equipment he needed to run experiments. “I was
> basically spending all of my time reading and thinking,” Medzhitov told me.

> Mostly, he thought about how our bodies perceive the outside world. We can
> recognise patterns of photons with our eyes and patterns of air vibrations
> with our ears. To Medzhitov, the immune system was another pattern
> recognition system – one that detected molecular signatures instead of light
> or sound.

> As Medzhitov searched for papers on this subject, he came across references
> to a 1989 essay written by Charles Janeway, an immunologist at Yale, titled
> ‘Approaching the Asymptote? Evolution and revolution in immunology’.
> Medzhitov was intrigued and used several months’ of his stipend to buy a
> reprint of the paper. It was worth the wait, because the paper exposed him
> to Janeway’s theories, and those theories would change his life.

Several _months_ of stipend to buy a single paper?

------
lossolo
I do not have any allergies, i was born in summer and was on fresh air a lot.
I have friends that were born in summer also but they were in house mostly and
those that were born in winter and they both have allergies. Lately i have
read scientific paper about statistically bigger amount of people with
allergies that didn't born in summer. So make your kid touch the mud and
ground, make it breath the air as much as he can while he is little. It's all
about environment and contact with it.. IF the kid is under "parents bubble"
when he is young it's not healthy for it.

Link: [https://theconversation.com/your-season-of-birth-is-
stamped-...](https://theconversation.com/your-season-of-birth-is-stamped-on-
your-dna-and-can-affect-your-risk-of-allergies-56751)

~~~
1_player
You're probably being downvoted (I did upvote by mistake...) because the
theory that being born in summer helps with allergies smells like BS.

One thing I agree with, though, with no other data point than my experience,
is that being in contact with allergens at a young age helps, or conversely
that kids raised in sterile environments are more prone to allergies and have
a weaker immune system.

I'm born in winter, my siblings as well, we were raised in the country, had
dogs/cats, didn't live in a very clean house and haven't found anything we're
allergic to and get very rarely sick.

But yeah, N=1

~~~
jrapdx3
I can see why you might say it "smells like BS", but it's not entirely
implausible. The parent referred to 2 elements: summertime birth, and "playing
in the mud", both contrasted to being confined to indoor environment.

"Born in summer" implies greater exposure to sunlight (in northerly latitudes)
vs. winter birth. Sunlight induces vitamin D formation in the skin. Vitamin D
is implicated in normal immune system development so low D levels in infancy
could conceivably be a factor in later development of allergies, etc.

"Playing in mud" suggests contact with organisms present in the natural
environment. Deprivation of this exposure has been discussed (here on HN a few
days ago) as the "old friends hypothesis".

Basically the idea is that through evolution our immune system "outsourced"
certain functions to co-evolving microorganisms. When contact with these
"friends" is lacking our immune systems are compromised and abnormal
hypersensitivities develop.

~~~
r00fus
The logic fails me - why would it matter if your first 3-4 months are sun
filled if the next 6 are snowy/rainy (repeat yearly)?

~~~
bobsoap
I believe the hypothesis is that age may very well play an important factor in
the development of the immune system. What your body learns in the first 3-4
months of your life is not equal to what it learns during the next 6... It's
moved on to other things.

That's actually how the brain works. Once you form a habit, for example, you
follow the developed pattern (now moved outside of the conscious level)
without thinking about it much anymore. It's how people learn how to walk,
talk, and basically do everything else they once learned in life with relative
ease... It's the brain's method of freeing up resources for other, new things.

It doesn't sound all that implausible to me that certain other mechanisms of
the body might perform in a very similar way.

------
csours
After all the build-up, this guy's theory doesn't sound new at all... Am I
missing something?

~~~
antisthenes
Not at all. I've heard this exact theory from relatives back in the 90's when
I asked them why people get allergies (as a kid).

------
tmaly
I found out about my daughters egg allergy while traveling abroad.

I have my own suspicion that it was the result of her having antibiotics when
she was a baby. A blocked tear duct was causing an infection in her eye. Her
pediatrician prescribed antibiotics.

When we eventually were able to get an appointment with an eye specialist, she
recommended just wiping the eye out with mild soap.

I have seen a few articles posted on HN that talked about the lack of gut
bacteria ( killed by antibiotics ) as the reason why children develop
allergies.

~~~
Cthulhu_
I've read other ones about the lack of breastfeeding at a young age; that
might actually also be related to the development of gut bacteria. Now I
wonder if breast milk is sterile or not (or contains spores); pretty sure
formula milk is / should be.

------
nkrisc
I'm still left wondering what this means for the fact some people are allergic
to things that others are not. Is it just genetics? My sister is allergic to
penicillin, onions, and mushrooms while I'm not allergic to anything I've yet
encountered. Did I just get lucky (or, maybe unlucky) and inherit different
genes from our parents? Does environment play a role?

------
libeclipse
How does this explain why only some people are affected by allergies. If it's
a defensive mechanism, shouldn't we all have it?

~~~
PeterisP
We all have this defensive mechanism, however, when it misfires (triggers in a
situation where the response isn't necessary) then we call it an allergy.

~~~
libeclipse
That's not what the article suggests. It suggests that allergies are not a
misfiring but rather a real and proper defense against the allergens.

------
jerryhuang100
The view of hypersensitive allergic reactions as a hypersensitive home alarm
system is very similar to the view in Chinese traditional medicine. In CT
medicine, to fundamentally treat constitutions of such hypersensitive
conditions, the treatment is more focus on long-term tuning / taming immune
system, rather than just blocking the allergic defenses.

------
barkbro
This would explain contact alleries to for example nickel and various
chemicals, which are usually quite harmful, but I don't see how this would
explain pollen and animal allergies. A lot of the pollens that cause allergy
in some people are coming from harmless plants. And with pollen spreading in
the wind, it would be an annoyance without necessarily protecting people much
against coming in contact with the plants. Would avoiding contact with certain
animals be beneficial? Other than avoiding pathogens, I don't see a lot of
reasons to do so.

Anyway, I wouldn't be surprised if allergy, like many things in biology, are
caused by multiple factors instead of just one.

~~~
fixermark
If I'm understanding correctly, the overall hypothesis is that the allergy
response is triggered by exposure to other toxins at low levels that prime the
immune system to respond to the toxin, but the priming is inaccurate; the
histamine-generating machinery does a quick-and-dirty approximation of the
chemical that triggered the cellular damage, and while rounding up whatever
industrial monomer irritated your nasal passages, it also snags the molecular
tags of surrounding pollen and other common chemicals.

As a side-effect, the system gets primed against the actual threat but also
primed against benign foreign chemicals as well. The change in the ecosystem
that has caused this defense mechanism to become a hindrance is the
introduction of novel chemicals to our daily lives that trip low levels of
immuno-response (or increase in chronic exposure to those chemicals due to a
general shift to indoor living, where the chemicals just sit in the
environment and bathe us in them), providing the opportunity for the immune
system to sensitize to frequenltly-contacted benign chemicals.

------
zbjornson
For a comparatively concise viewpoint straight from Medzhitov's group,
including much more context and scientific support, see:
[http://www.cell.com/current-
biology/fulltext/S0960-9822(12)0...](http://www.cell.com/current-
biology/fulltext/S0960-9822\(12\)00820-2) (free)

This also spends more time discussing what only appears in the last few
paragraphs above the " __* " in the OP, regarding Westernization efects and
what I think are the more controversial aspects.

------
gumby
To me the most interesting part of allergies is not addressed by this article,
except by referring to its absence: > Instead, allergists should be learning
why a minority of people turn a protective response into a hypersensitive one.
“It’s the same as with pain,” said Medzhitov. “No pain at all is deadly;
normal pain is good; too much pain is bad.”

It's clear that there's a process, presumably a good one, that sometimes goes
haywire, and really that's all most people care about.

------
nxzero
Reminds me how if you ask someone why something is and they lack the knowledge
to know why, they'll still try to give an answer based on what they do know.

We may never know why people have allergies.

------
sophacles
Perhaps someone here is more versed in the field and can help me understand
something...

It seems like the "parasite" theory is a more specific example of the "fast
reaction to toxins" theory being presented. Are there bigger differences that
I'm not understanding, or is the resistance to the idea just that the new
theory is overgeneralizing?

------
Jacksonb
Good complimentary paper. "Impact of Pollen on Human Health: More Than
Allergen Carriers?"
[https://mediatum.ub.tum.de/doc/1218587/1218587.pdf](https://mediatum.ub.tum.de/doc/1218587/1218587.pdf)

------
wyck
They should do some research on tree pollen and why my body thinks trees are
trying to kill me.

------
ArtDev
I wonder if having worms as a kid (I was an expat kid in Nepal) provides some
kind of protection against allergies as an adult?

I have never had any allergies and I think this may be the reason (both my
parents have seasonal allergies).

------
dahart
"sepsis. It is thought to strike around a million people a year in the USA
alone, up to half of whom die."

Holy crap, really? I looked it up and yeah, it's true. I had no idea sepsis
killed that many people.

------
beefman
Original source: [http://mosaicscience.com/story/why-do-we-have-
allergies](http://mosaicscience.com/story/why-do-we-have-allergies)

~~~
dang
Ok, we changed to that from [http://qz.com/689806/a-controversial-theory-may-
explain-the-...](http://qz.com/689806/a-controversial-theory-may-explain-the-
real-reason-humans-have-allergies/).

------
outworlder
If allergies are protective, what happens to people who take anti-allergy
medication? Say, during pollen season? Are they being harmed?

~~~
scotty79
That would depend on whether those medications only reduce strong allergic
reaction or reduce all allergic reactions, even small ones.

------
unusximmortalis
unless our health is damaged by an external factor (a hammer, a bigger hammer,
you get the point) all diseases are internal reactions of our bodies (caused
by outside or inside interactions) which unbalance our whole being and
eventually can kill us if we do not restore the balance in timely manner.

------
2skep
This article is a very good example of the genre of science reporting I find
very uninteresting and even boring. The way the writer builds up to the punch
line by weaving in his own life and by overemphasiaing the trope of the
'maverick scientist challenging group think' is so contrived that it probably
wrote itself.

Maybe I am different that I want to read science articles to learn new things
and not to be entertained. The writer proves how hard it is to do both.

~~~
wmeredith
I read pieces like this and I can't help but think that the writer is creating
prose, and I want reporting. one of us is in the wrong place.

------
hellbanner
If you think you may have parasites, check out
[http://humaworm.com](http://humaworm.com) and the related herb remedies

~~~
rhexs
If you think you may have parasites, perhaps consider going to a real doctor.

~~~
ArtDev
Its a funny thing but the "natural" remedy can actually work better. I put
natural in quotations because its super toxic!

Wormwood/nutmeg/Black Walnut. Nasty stuff.

Its good as a last resort if the conventional stuff does not kill the
parasites

This is what happened to me.

~~~
askldfhjkasfhd
I would argue that ingesting something that's super toxic is not a better
solution, and is part of the reason why naturopathic remedies are not a good
idea to self-appy.

~~~
hellbanner
"Antibiotics" literally translates to anti-living, if my language knowledge is
correct..

------
venomsnake
I grew up in Eastern Europe (born in the early 80s). In my cohort hay fever
allergies are extremely rare and food ones are unheard of.

In the recent generations there are definitely more of them. EE was
notoriously lax with pollution and industrial waste. So I think that toxins
are not to be blamed.

The sterility hypothesis seems like a better explanation.

~~~
babuskov
I don't know about food allergies, but for hay fever I think the allergies
were there before - people weren't educated enough to recognize the symptoms.
My father (born in 1948) got fed with anti-biotics for the first 40 years of
his life until one day he was lucky enough that a new local physician arrived
who had allergy problems himself and changed the therapy.

I was born in 1977, and also remember all the anti-biotics injections I got as
a child until they finally tested me for allergies at the age of 12.

I'd say the majority of medical doctors in this area got aware on allergies in
early 90's.

------
Aelinsaar
I think the "It's a blunder" view is simplistic, but so is, "It's wonderfully
adaptive!" I think like the sensation of pain, or itch, it can be both. When
it's working well, in moderation, and your environment is stable, you're going
to be ok. If one of those elements goes awry, then bang.

Being slightly allergic to something noxious makes sense, but being violently,
potentially fatally allergic to a foodstuff? No...

------
aaron695
Not sure is this article mentioned it, but from another one

"As for why allergies are seemingly on the rise, this work does nothing to
dispel or support the so-called hygiene hypothesis, which links allergies to
modern hyperclean environments. With the advent of clean water and childhoods
devoid of consuming much dirt (and the millions of bacteria and viruses that
come with them) the immune system does not receive the early training it needs
to function correctly, the hypothesis says. A healthy exposure to those
invaders leads the body to invest more in type 1 responses, including strong
microbe defense, rather than type 2 reactions such as allergies."

~~~
lordnacho
Sounds like an opening for a new type of vaccine?

~~~
criddell
Can a doctor write a prescription to allow a kid to play in the mud?

~~~
lordnacho
I've heard of doctors telling people to drink Guinness.

~~~
criddell
Ah right. I forgot that someone with a PhD in history is also a doctor.

------
bokglobule
FWIW, I was able to clear up my spring time pollen allergies by not eating
gluten.

I was tested for celiac disease, but I do not have it thankfully. However, I
decided to stop eating wheat in early 2015 for other reasons. I noticed that
when spring came, I had almost no issues with pollen. I mentioned it to my
internist and he said he wasn't surprised given the typical immune reaction to
gluten. This year, another repeat performance. Almost no problems with pollen
season. I had one or two episodes where I sneezed, but that was it. My area of
the US is one of the highest allergy areas due to the density of foliage.

As to why this has happened, I can only speculate. I suspect that it's mostly
due to the fact that the wheat we eat in the U.S. isn't the same wheat we ate
40+ years ago- it's been genetically altered and there are NO long term
studies on the affect of these GMOs on health - they haven't been available on
the market long enough to really know. I haven't tried eating non-GMO wheat
products so I can't say whether my theory is correct. For me, not eating wheat
was the way to go for better health overall. But.. I do miss eating warm bread
from the oven now and then.

~~~
partiallypro
None of what you said is backed by science, and people had allergies long
before GMO crops ever existed. There have been tons of studies on GMO crops,
long term and short term effects and there has been no link between them and
anything even as nuanced as allergies.

Every time people speak out against GMO crops, they are following their own
faith instead of science. Golden rice could have saved hundreds of thousands
of people from death or malnutrition, but those people died because of people
that spout this nonsense.

~~~
nashashmi
> None of what you said is backed by science,

There is nothing out there to disprove what people fearfully claim either. The
long term effects on a large were never tested, and it is being tested while
in production. Unfortunately, there is no control case to compare against.

>and people had allergies long before GMO crops ever existed.

Sure there were people with allergies long before GMOs but they were in
smaller numbers.

There has been a growing trend of abnormalities and scientists cannot
understand why. GMOs cannot be ruled out.

~~~
partiallypro
> There is nothing out there to disprove what people fearfully claim either.

That's not how burden of proof works.

> Sure there were people with allergies long before GMOs but they were in
> smaller numbers.

Besides the fact that you've made this assertion based on no data what so
ever, even if the data existed from the 1800s it's unlikely it would be that
good as most people would just not report it and had no access to medical
treatment.

> There has been a growing trend of abnormalities and scientists cannot
> understand why.

Such as?

