10 ms·

Your Immune System Is Not a Muscle

287 points by awendland 2y ago

sirspacey 2y ago
Fascinating read and novel hypothesis on the increase in allergies.
bhk 2y ago
Interesting that in one of the cited studies the authors are not afraid to claim that viral infections may cause autoimmune diseases, despite the fact that the potential mechanisms they list could also apply to vaccines. "Current research suggests that several mechanisms, such as molecular mimicry, epitope spreading, and bystander activation, can cause viral-induced autoimmunity."
- giantg2 2y ago
  Autoimmune responses are well known with some vaccines and some conditions, such as GBS. Most real experts know that vaccines carry all sorts of risks. It's the general public that is mostly unaware and would find this sort of thing surprising. It's the whole "safe" vs "generally safe" thing.
  - krackers 2y ago
    >Most real experts know that vaccines carry all sorts of risks And that's why all the real experts made sure to properly communicate the risks vs benefits of the Covid vaccine in an age, sex, and dose-stratified fashion, right? Oh wait...
    - randomdata 2y ago
      The real experts in the fields I know well don't tend to spend much time communicating with others about their expertise, especially to the layman. Why would the real experts in this particular field be any different?
    - XMPPwocky 2y ago
      Experts in any field are generally not the ones communicating with, and making recommendations to, the public.
    - pjc50 2y ago
      The high level of insanity of public debate made people shut up. I know at least one immunologist who quit Twitter fairly early on in the pandemic because of it. Doing health communication has hazards of its own.
  - nielsbot 2y ago
    What is GBS? And the vaccine for it causes autoimmune responses? Can I read more?
    - giantg2 2y ago
      GBS is the autoimmune response to many vaccines. In a lot of ways, it's similar to having a stroke in as far as people have to relearn how to do many things, sometimes down to relearning how to walk.
- projektfu 2y ago
  Why would they be afraid? These are well-worn paths of research. I doubt anyone would be censored for referring to the vaccine-related injuries in 1976 and the proposed pathogenesis mechanisms, including molecular mimicry.
- pazimzadeh 2y ago
  When a virus replicates inside your cells, it sets off alarms that as a result of sensing of viral nucleic acid signatures in your cells (i.e. MAVS https://en.wikipedia.org/wiki/Mitochondrial_antiviral-signaling_protein https://en.wikipedia.org/wiki/Mitochondrial_antiviral-signal...). A vaccine, unless it is a live attenuated vaccine (these are rare) does not set off the same alarms since you don't actually get viral nucleic acids in your cells.
Xcelerate 2y ago
I don’t know enough to comment on the Hygiene / Old Friends hypothesis, but anecdotally it seems like almost everyone I know now has an allergy or autoimmune disorder of some sort. After giving birth, my sister suddenly developed something similar to celiac disease (but not quite the same; I don’t think doctors ever figured out exactly what it is) to where she can’t eat grains and a few other types of food as well. I used to get eczema occasionally, but now it seems to have morphed into a permanent rash that continuously moves to different locations over my body. And my wife had food allergy testing done a couple of years ago due to constant stomach pain and has now eliminated chocolate, seafood, peaches, and many other foods from her diet. It’s bizarre. We really need to figure out what’s going on before everyone has a diet prepared by their pharmacist alongside all of the pills needed to cope with their autoimmune pain.
- ransom1538 2y ago
  IHMO An old myth, I believe: Your immune system needs something to fight, otherwise, it starts finding problems that aren't.
  - moffkalast 2y ago
    Less of an old myth and more like well accepted scientific fact: https://www.nature.com/articles/s41591-019-0675-0 https://www.nature.com/articles/s41591-019-0675-0 Excess calorie intake causes chronic inflammation, which gradually causes a plethora of other problems. There's also autoimmune conditions as a consequence of viral infections, so many of that from covid in recent years.
  - DontchaKnowit 2y ago
    I had an allergist tell me about a study that supported this idea recently : Introduction of pig whipworm eggs into the digestive tract of IBS patients reduced symptoms for a some patients. Pretty fascinating actually. I was seeing the allergist for my eczema and he asked me if I experienced symptom relief when traveling abroad, which I did in Honduras. He thought I may have been exposed to a parasite there that diverted my overactive immune response. go figure. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149054/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149054/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856386/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856386/
evrydayhustling 2y ago
I'm confused about some of the implications regarding crowd infections. Certainly for some of these -- say, Chicken Pox -- we know that early and controlled exposure is preferable to a first case later in life. And that the cycle of herd immunity in survivors leads to endemicity and less deadly strains. It seems like both things can be true: it's best not to get infections at all, but if you live in a world where you will get infected, doing so early and outside a correlated epidemic can be advantageous. And, while our immune system evolved for a different social density, it still plays a critical role in mitigating the long-term collective impact of crowd infections.
- abracadaniel 2y ago
  Chicken pox also returns as shingles in adulthood if you got the actual virus instead of the vaccine.
  - idunnoman1222 2y ago
    Even if you got the vaccine, you can still get shingles
    - tim333 2y ago
      Though it's less common.
- jph00 2y ago
  We used to think that "early and controlled exposure is preferable to a first case later in life" for chicken pox, but AFAICT that's no longer widely accepted in most western countries. Chicken pox in children can lead to serious complications in some cases, including bacterial skin infections, pneumonia, and encephalitis. The virus remains dormant in the body and can reactivate later in life as shingles. Now that there's an effective 2-shot vaccine, that's the recommended approach.
pbhjpbhj 2y ago
>We can see that not all obstacles make you stronger. Destroy the cartilage in your knee, and it may never fully recover, since cartilage doesn’t grow back. // I'm not a medic but I recall this being disproven or shown to be at least partially a myth a few years ago - https://physicians.dukehealth.org/articles/humans-have-salamander-ability-regrow-cartilage-joints https://physicians.dukehealth.org/articles/humans-have-salam... from 2020, for example. Researchers showed that ankle cartilage is younger than knee- and younger still than hip cartilage. Indicating that it grows back in ankles relatively quickly. As the article says, analogies can mislead us, but this didn't inspire confidence. I could probably dismiss it if the article weren't about being scientifically precise and dispelling myths relating to human biology. Good piece, but the title is misleading too as the conclusion appears to be "it's complicated; yes and no".
- Mistletoe 2y ago
  Also runners have great knee cartilage compared to sedentary people, despite the myth. >Using motion capture and sophisticated computer modeling, the study confirms that running pummels knees more than walking does. But in the process, the authors conclude, running likely also fortifies and bulks up the cartilage, the rubbery tissue that cushions the ends of bones. https://www.nytimes.com/2020/10/21/well/move/why-running-wont-ruin-your-knees.html https://www.nytimes.com/2020/10/21/well/move/why-running-won...
  - HappMacDonald 2y ago
    Is that causative though? Or do people with great cartilage simply enjoy running more because it isn't as painful?
    - TeaBrain 2y ago
      Why this way of looking at cartilage is a misconception is explained in the study cited by the top level comment. Cartilage in different parts of the body has been shown to be different ages, indicating that it rejuvenates and that there there isn't just a single set of good or bad cartilage.
hyperpape 2y ago
I'm (genuinely--I don't know enough to pretend this is a knock-down argument) curious how this characterization of "crowd" illnesses fits with reports that Covid was extensively circulating in deer (not known for congregating in indoor spaces with poor ventilation). https://www.unmc.edu/healthsecurity/transmission/2023/08/29/latest-covid-twist-coronavirus-is-spreading-in-deer-study-finds-and-many-are-getting-it-from-humans/ https://www.unmc.edu/healthsecurity/transmission/2023/08/29/...
- yieldcrv 2y ago
  If its surviving in deer longer than it would in a human, then all calculus about the virus is different either way. There wouldn't be a need to conform that data to this observation.
- Terretta 2y ago
  No idea either — but humans tend to exchange less blood than deer (via thickets of ticks).
- tim333 2y ago
  Not a deer expert but they can probably spread it by licking stuff, drinking from the same puddle and the like.
iwontberude 2y ago
> may never fully recover, since cartilage doesn’t grow back Doesn't this categorically mean cartilage injuries never fully recover because the cartilage doesn't grow back?
kens 2y ago
My "unpopular opinion" is that in 100 years, people will consider it very strange that most of the population was permanently infected with a bunch of viruses like EBV/HSV/CMV/HPV and nobody cared or did anything about it.
- whythre 2y ago
  Probably an accurate prediction. Kind of like how large populations in the American south were once infected with hookworm.
  - from-nibly 2y ago
    Also now we don't have enough hookworm. Cause apparently that has caused a lot of auto immune disorders.
- darby_nine 2y ago
  No governments cared or did anything about it, you mean.
  - Terretta 2y ago
    Governments were doing something about it until all the fifth dentists* got amplified by “journalists” in the “media” we now recognize are mostly just wannabe influencers playing pundit drumming up clicks. * "4 out of 5 dentists agree" except it's more like the 50th dentist, given research consensus
  - stephen_g 2y ago
    With HPV, the Government here (Australia) partially funded the research that led to an HPV vaccine (Gardisil) that helps prevent a bunch of cancers and now all school children here get it for free... So it does happen, just slowly...
- glitchcrab 2y ago
  Almost certainly, but you're forgetting one thing - hindsight. We can look back a hundred years from today and say that treatments back then were very misguided (and possibly even barbaric). Knowledge and science advance with time.
modeless 2y ago
This is an excellent article. Too many people believe that kids getting colds will help their immune system get stronger. In reality, getting sick is almost never beneficial. The information about the hygiene hypothesis and how it is really more about "old friends" is also very important and not widely understood. Many don't know about the hygiene hypothesis at all and those who do usually interpret it incorrectly.
- nradov 2y ago
  Kids getting colds allows them to develop immunity to some of the hundreds of endemic upper respiratory viruses that constantly circulate throughout the human population. They're going to get infected with many of them sooner or later, so better to get it over with sooner. This protects them later in life when their immune systems are less effective.
  - francisofascii 2y ago
    Yeah, but many of the viruses mutate rapidly, so the immunity gained from a cold virus from years ago won't help much today.
  - jph00 2y ago
    I haven't seen any research to support that contention -- rather, everything I've seen suggests you don't get coronaviruses like colds once off, so you don't "get it over with". Instead, they can weaken your immune system and these viruses can stay around for years, as discussed in the article.
    - nradov 2y ago
      The article is a mix of half-truths and speculation with a few random facts sprinkled in. It doesn't represent any sort of scientific consensus. Don't take it too seriously. Infections with typical rhinoviruses and coronaviruses build adaptive immunity to those viruses (as well as those that are genetically similar). This typically reduces the severity of subsequent infections. They didn't stay around for years. When we talk about things that "strengthen" or "weaken" the immune system that's really an oversimplification. There's a lot more going on in the complete system.
Nasrudith 2y ago
Similar to the "old friends" theory, I personally thought the issue with allergies and parasites suppressing allergies as a "calibration issue". Where evolution effectively set the dominant immune-systems to what would be hypersensitive in an environment without parasites order to compensate for parasites immuno-suppressing to protect themselves. Sort of like how sickle cell anemia genes were selected for its malaria resistance, in spite of how bad it is to be born with two copies of the gene.
SoftTalker 2y ago
> Comparing the immune system to a muscle that gets stronger with use is overly simplistic and, in many cases, inaccurate. But a vaccine does something analogous: it "exercises" the immune system (hopefully harmlessly) to strengthen it for when real pathogens are encountered. So between vaccines, and natural immunities developed by exposure to and recovering from a disease, the "getting stronger with use" comparison is generally correct.
- bink 2y ago
  But it isn't the "exercising" of the immune system that provides the benefit, it's training it to recognize a new virus. If that could be done without a huge immune response it would be just as effective. The immune system isn't any stronger after a vaccination, it's just smarter. Presumably exposing the immune system to several unrelated viruses provides no benefits as to how it can deal with the target virus.
  - dudeofea 2y ago
    unlikely you could achieve that given that vaccine manufacturers purposely add adjuvants to annoy your immune system to in turn create a stronger immune response for higher antibody titers, which last longer. https://www.sciencedirect.com/topics/medicine-and-dentistry/vaccine-adjuvant https://www.sciencedirect.com/topics/medicine-and-dentistry/...
alecst 2y ago
I guess I'm cool coming out and saying it. Out of curiosity I bought some helminths online and infected myself. I was inspired to do it after reading a book called An Epidemic of Absence. I can't say a whole lot -- positive or negative -- came from it, but it was easy to do and inexpensive. So even though the article says you shouldn't try it at home, I did. I consider it safe. I'm not a doctor, I just read a lot of PubMed, so take that for what it's worth.
BlueTemplar 2y ago
Why would this co-evolution history with parasites have only started with Homo Sapiens ?
- jmull 2y ago
  It wouldn't and I don't think they are really trying to say that it did. It's just that you have to start your analysis somewhere, and, obviously, our own evolutionary branch (i.e. homo sapiens) is the most relevant.
pazimzadeh 2y ago
The Old Friends hypothesis doesn't make a ton of sense to me. Viruses did not come around much later than bacteria and parasites, and definitely before the adaptive immune system. Bacterial viruses may have been involved in the evolution of nuclei https://nyaspubs.onlinelibrary.wiley.com/doi/full/10.1111/j.1749-6632.2009.04994.x https://nyaspubs.onlinelibrary.wiley.com/doi/full/10.1111/j.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infected the gametes of our fishy ancestors https://www.nature.com/articles/29457 https://www.nature.com/articles/29457 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686171/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686171/ More likely is that there is a critical time window during the development of the immune system when it is trained not to react to most bacteria (which are passed on from the mother's vaginal microbiota and harmed by cesarian sections and early antibiotic use). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904599/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904599/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464665/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464665/ There's more and more evidence that one person's commensal bacteria can be someone else's pathogen, and that we should really think about it as a "lock and key" with your immune system rather than categorizing bacteria as inherently good or bad. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300855/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300855/ Another rarely mentioned complication though is that the successful immune response itself likely selects for more pathogenic microbes. https://pubmed.ncbi.nlm.nih.gov/15539148/ https://pubmed.ncbi.nlm.nih.gov/15539148/ Removing selective pressure from pathogens can actually lead to less virulent strains. https://pubmed.ncbi.nlm.nih.gov/30100182/ https://pubmed.ncbi.nlm.nih.gov/30100182/ That may be why the body spends considerable resources feeding the microbiota at a slow pace using by secreting mucus which contains a large amount of sugars, but which are attached using an extreme amount of diverse linkages so that one bacteria cannot sweep the field and take over. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1134114/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1134114/ https://www.nature.com/articles/s41522-023-00468-3 https://www.nature.com/articles/s41522-023-00468-3 You cannot really withhold food from bacteria, they will just eat you. But if you give them a slow trickle of sugar, you remove their reason to invade you (which is is at a risk to themselves). I personally think this concept can be applied to wars and immigration, but anyway.. Why are viruses more likely to cause autoimmune diseases than parasites? Probably because viruses go inside us and set of (Th1) intracellular responses , whereas parasites set of extracellular responses (Th2). You're probably more likely to be tricked into attacking yourself when you are fighting off something inside yourself than something outside your cells.
cjbgkagh 2y ago
Very much disagree with the implication that helminths will help very much for these conditions. While not a commonly known treatment in the 'medical sphere' it's is very commonly known in the 'patient community spheres' and from the patient run studies it does not appear to have a particularly strong effect. It does appear to help some people so it's hard to rule it out but that could easily be noise. Those who did report a benefit were most often in the less impaired category and those same people tend to benefit from a wide variety of treatments that are generally ineffective on those of use who are more impaired. This post reads like someone who has just discovered the world of ME/CFS/LongCovid (post viral) /ToxicMold/POTs/SIBO/IBS/Lymes/hEDS/Graves/Hashimotos/MS/Lupus etc. etc. As a lifer I have seen many people enter the space and go through this exact same early stage of discovery. What I really think it is; it's genetic, various types of generalized anxiety disorders with their associated auto-immune conditions with the most common being Hypermobile Ehlers Danlos. These genetic predispositions are made worse by diet and lifestyles and triggered by all manner of stressors. On how to treat it, Low Dose Naltrexone is a good step one, then meds for dysautonomia, TUDCA, 3,3′-diindolylmethane (DIM), and then finally I think Low Dose Semaglutide < 0.1mg per week is going to be huge for auto-immune. It's early stages but few things have appeared more promising in the patient community. It worked wonders for me and a few other people I know. Everyone is different but those are in my opinion a good place to for someone starting. Helminths did not work for me the several times I tried it and have not worked for anyone that I have personally known that has tried it which to date is around ~10pp. But I do believe the people who do say it has worked for them but I don't count them unless I knew them prior due to the issue of selection criteria biases.
- jph00 2y ago
  But the article isn’t implying that. In fact it explicitly says that helminths can be dangerous.
- pazimzadeh 2y ago
  The Th1 program in a T-helper cell suppresses the Th2 response, and vice versa. https://en.wikipedia.org/wiki/T_helper_cell#Th1/Th2_model https://en.wikipedia.org/wiki/T_helper_cell#Th1/Th2_model Although it's way more complicated than that and there are exceptions, but it's still a real phenomenon. Community deworming increases Th1 cytokines https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098677/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098677/ When you administer helminths to yourself there is no guarantee that they are going to the right spot in your body, etc. which explains why everyone responds differently.
Terr_ 2y ago
> Some people compare the immune system to a muscle To reiterate something from a recent discussion on air purifiers [0], if your body is a civilization of cells then activating the adaptive immune system is like unleashing Skynet [1] to stop a potential zombie apocalypse. Even if Skynet reliably wins, you're losing at least a few cities as glowing craters, and each time you're rolling the dice hoping that not too many of the murder-bots go rogue before you can make them self-destruct or go back into storage. You definitely do not want to slam that big red button just because of one police report of a human biting another human, or a report that a bunch of people with green skin are marching down the road, etc. As we studying the adaptive immune system, we keep discovering safety-interlocks and subtle feedback loops, which presumably evolved because our relatives without them simply tore themselves apart a bit too often. [0] https://news.ycombinator.com/item?id=41347868#41348890 https://news.ycombinator.com/item?id=41347868#41348890 [1] https://en.wikipedia.org/wiki/Skynet_(Terminator) https://en.wikipedia.org/wiki/Skynet_(Terminator)
pella 2y ago
I prefer the antifragile metaphor. "The immune system is an example of antifragility in the natural world since an effective response is only produced in the presence of an antigen threat, but the response leaves the body better able to respond in future. The presence of an antigen activates the immune response, which not only deals with the immediate challenge through the innate immune system in the short term and long term through the adaptive immune system but also provides ongoing protection against this and similar future threats through the immunological memory of B cells. In other words, exposure to an invading antigen leaves the body stronger than before, so the stressor has created a benefit that was neither present nor possible before it occurred." read more: "Beyond resilience: towards antifragility?" https://scholar.google.com/scholar?cluster=13108278257209181454 https://scholar.google.com/scholar?cluster=13108278257209181... ------ And see the -> https://en.wikipedia.org/wiki/Variolation https://en.wikipedia.org/wiki/Variolation "Variolation was the method of inoculation first used to immunize individuals against smallpox (Variola) with material taken from a patient or a recently variolated individual, in the hope that a mild, but protective, infection would result. Only 1–2% of those variolated died from the intentional infection compared to 30% who contracted smallpox naturally. Variolation is no longer used today. It was replaced by the smallpox vaccine, a safer alternative. This in turn led to the development of the many vaccines now available against other diseases."
highfrequency 2y ago
Wow - meningitis lowers IQ by 5 points
- incanus77 2y ago
  Bacterial does, viral does not appear to. I am a survivor of bacterial meningitis and sepsis at eight months and fortunately do not experience any known side effects. However, the IQ effect is sobering.
HarHarVeryFunny 2y ago
So, drop food on kitchen floor - pick it up and eat it (without washing) good or bad?
- giraffe_lady 2y ago
  Other than norovirus and salmonella most foodborne illness isn't infection, it's intoxication from metabolic byproducts that need time to accumulate to sufficient levels. The biggest risk here is either a chemical contaminant from a non-foodsafe cleaning product on your floor, or a physical one like a small shard of broken glass sticking to it.
prologist11 2y ago
It's actually a lot more interesting than what the article explains here. The immune system essentially goes through a process of hypermutation and can be compared to a hashmap which is populated during the first few years of one's life. After that the hashmap is essentially frozen. This is why early immunization is very important because being exposed to mild pathogens when young helps one's immune system recognize and deal with similar pathogens later in life. The immune system only gets worse over time which is why eventually most viral infections overwhelm the immune system and either cause death or cancer.
- Temporary_31337 2y ago
  That eventually can be over 100 years sometimes? Can you point to some research about immunity being much stronger acquired early on? For some vaccines boosters are needed anyway.
  - prologist11 2y ago
    Here you go: https://meshb.nlm.nih.gov/record/ui?name=Immunoglobulin+somatic+hypermutation https://meshb.nlm.nih.gov/record/ui?name=Immunoglobulin+soma...
Anitalawson 2y ago
[dead]
pollies 2y ago
[flagged]
tim333 2y ago
>Our immune systems evolved for a different world (that didn’t involve 100,000 global flights per day). Googling how it was then: >Around 12,000 years ago and earlier, life expectancy was about 33 years. Infections, such as diarrheal diseases that led to starvation and dehydration, were the leading cause of death, accounting for about 75% of deaths. so the modern stuff is not so bad really.

287 points by awendland 2y ago

Fascinating read and novel hypothesis on the increase in allergies.

bhk 2y ago

Interesting that in one of the cited studies the authors are not afraid to claim that viral infections may cause autoimmune diseases, despite the fact that the potential mechanisms they list could also apply to vaccines. "Current research suggests that several mechanisms, such as molecular mimicry, epitope spreading, and bystander activation, can cause viral-induced autoimmunity."

giantg2 2y ago
Autoimmune responses are well known with some vaccines and some conditions, such as GBS. Most real experts know that vaccines carry all sorts of risks. It's the general public that is mostly unaware and would find this sort of thing surprising. It's the whole "safe" vs "generally safe" thing.
- krackers 2y ago
  >Most real experts know that vaccines carry all sorts of risks And that's why all the real experts made sure to properly communicate the risks vs benefits of the Covid vaccine in an age, sex, and dose-stratified fashion, right? Oh wait...
  - randomdata 2y ago
    The real experts in the fields I know well don't tend to spend much time communicating with others about their expertise, especially to the layman. Why would the real experts in this particular field be any different?
  - XMPPwocky 2y ago
    Experts in any field are generally not the ones communicating with, and making recommendations to, the public.
  - pjc50 2y ago
    The high level of insanity of public debate made people shut up. I know at least one immunologist who quit Twitter fairly early on in the pandemic because of it. Doing health communication has hazards of its own.
- nielsbot 2y ago
  What is GBS? And the vaccine for it causes autoimmune responses? Can I read more?
  - giantg2 2y ago
    GBS is the autoimmune response to many vaccines. In a lot of ways, it's similar to having a stroke in as far as people have to relearn how to do many things, sometimes down to relearning how to walk.
projektfu 2y ago
Why would they be afraid? These are well-worn paths of research. I doubt anyone would be censored for referring to the vaccine-related injuries in 1976 and the proposed pathogenesis mechanisms, including molecular mimicry.
pazimzadeh 2y ago
When a virus replicates inside your cells, it sets off alarms that as a result of sensing of viral nucleic acid signatures in your cells (i.e. MAVS https://en.wikipedia.org/wiki/Mitochondrial_antiviral-signaling_protein https://en.wikipedia.org/wiki/Mitochondrial_antiviral-signal...). A vaccine, unless it is a live attenuated vaccine (these are rare) does not set off the same alarms since you don't actually get viral nucleic acids in your cells.

Xcelerate 2y ago

I don’t know enough to comment on the Hygiene / Old Friends hypothesis, but anecdotally it seems like almost everyone I know now has an allergy or autoimmune disorder of some sort. After giving birth, my sister suddenly developed something similar to celiac disease (but not quite the same; I don’t think doctors ever figured out exactly what it is) to where she can’t eat grains and a few other types of food as well. I used to get eczema occasionally, but now it seems to have morphed into a permanent rash that continuously moves to different locations over my body. And my wife had food allergy testing done a couple of years ago due to constant stomach pain and has now eliminated chocolate, seafood, peaches, and many other foods from her diet. It’s bizarre. We really need to figure out what’s going on before everyone has a diet prepared by their pharmacist alongside all of the pills needed to cope with their autoimmune pain.

ransom1538 2y ago
IHMO An old myth, I believe: Your immune system needs something to fight, otherwise, it starts finding problems that aren't.
- moffkalast 2y ago
  Less of an old myth and more like well accepted scientific fact: https://www.nature.com/articles/s41591-019-0675-0 https://www.nature.com/articles/s41591-019-0675-0 Excess calorie intake causes chronic inflammation, which gradually causes a plethora of other problems. There's also autoimmune conditions as a consequence of viral infections, so many of that from covid in recent years.
- DontchaKnowit 2y ago
  I had an allergist tell me about a study that supported this idea recently : Introduction of pig whipworm eggs into the digestive tract of IBS patients reduced symptoms for a some patients. Pretty fascinating actually. I was seeing the allergist for my eczema and he asked me if I experienced symptom relief when traveling abroad, which I did in Honduras. He thought I may have been exposed to a parasite there that diverted my overactive immune response. go figure. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149054/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3149054/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856386/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1856386/

evrydayhustling 2y ago

I'm confused about some of the implications regarding crowd infections. Certainly for some of these -- say, Chicken Pox -- we know that early and controlled exposure is preferable to a first case later in life. And that the cycle of herd immunity in survivors leads to endemicity and less deadly strains. It seems like both things can be true: it's best not to get infections at all, but if you live in a world where you will get infected, doing so early and outside a correlated epidemic can be advantageous. And, while our immune system evolved for a different social density, it still plays a critical role in mitigating the long-term collective impact of crowd infections.

abracadaniel 2y ago
Chicken pox also returns as shingles in adulthood if you got the actual virus instead of the vaccine.
- idunnoman1222 2y ago
  Even if you got the vaccine, you can still get shingles
  - tim333 2y ago
    Though it's less common.
jph00 2y ago
We used to think that "early and controlled exposure is preferable to a first case later in life" for chicken pox, but AFAICT that's no longer widely accepted in most western countries. Chicken pox in children can lead to serious complications in some cases, including bacterial skin infections, pneumonia, and encephalitis. The virus remains dormant in the body and can reactivate later in life as shingles. Now that there's an effective 2-shot vaccine, that's the recommended approach.

pbhjpbhj 2y ago

>We can see that not all obstacles make you stronger. Destroy the cartilage in your knee, and it may never fully recover, since cartilage doesn’t grow back. // I'm not a medic but I recall this being disproven or shown to be at least partially a myth a few years ago - https://physicians.dukehealth.org/articles/humans-have-salamander-ability-regrow-cartilage-joints https://physicians.dukehealth.org/articles/humans-have-salam... from 2020, for example. Researchers showed that ankle cartilage is younger than knee- and younger still than hip cartilage. Indicating that it grows back in ankles relatively quickly. As the article says, analogies can mislead us, but this didn't inspire confidence. I could probably dismiss it if the article weren't about being scientifically precise and dispelling myths relating to human biology. Good piece, but the title is misleading too as the conclusion appears to be "it's complicated; yes and no".

Mistletoe 2y ago
Also runners have great knee cartilage compared to sedentary people, despite the myth. >Using motion capture and sophisticated computer modeling, the study confirms that running pummels knees more than walking does. But in the process, the authors conclude, running likely also fortifies and bulks up the cartilage, the rubbery tissue that cushions the ends of bones. https://www.nytimes.com/2020/10/21/well/move/why-running-wont-ruin-your-knees.html https://www.nytimes.com/2020/10/21/well/move/why-running-won...
- HappMacDonald 2y ago
  Is that causative though? Or do people with great cartilage simply enjoy running more because it isn't as painful?
  - TeaBrain 2y ago
    Why this way of looking at cartilage is a misconception is explained in the study cited by the top level comment. Cartilage in different parts of the body has been shown to be different ages, indicating that it rejuvenates and that there there isn't just a single set of good or bad cartilage.

hyperpape 2y ago

I'm (genuinely--I don't know enough to pretend this is a knock-down argument) curious how this characterization of "crowd" illnesses fits with reports that Covid was extensively circulating in deer (not known for congregating in indoor spaces with poor ventilation). https://www.unmc.edu/healthsecurity/transmission/2023/08/29/latest-covid-twist-coronavirus-is-spreading-in-deer-study-finds-and-many-are-getting-it-from-humans/ https://www.unmc.edu/healthsecurity/transmission/2023/08/29/...

yieldcrv 2y ago
If its surviving in deer longer than it would in a human, then all calculus about the virus is different either way. There wouldn't be a need to conform that data to this observation.
Terretta 2y ago
No idea either — but humans tend to exchange less blood than deer (via thickets of ticks).
tim333 2y ago
Not a deer expert but they can probably spread it by licking stuff, drinking from the same puddle and the like.

iwontberude 2y ago

> may never fully recover, since cartilage doesn’t grow back Doesn't this categorically mean cartilage injuries never fully recover because the cartilage doesn't grow back?

kens 2y ago

My "unpopular opinion" is that in 100 years, people will consider it very strange that most of the population was permanently infected with a bunch of viruses like EBV/HSV/CMV/HPV and nobody cared or did anything about it.

whythre 2y ago
Probably an accurate prediction. Kind of like how large populations in the American south were once infected with hookworm.
- from-nibly 2y ago
  Also now we don't have enough hookworm. Cause apparently that has caused a lot of auto immune disorders.
darby_nine 2y ago
No governments cared or did anything about it, you mean.
- Terretta 2y ago
  Governments were doing something about it until all the fifth dentists* got amplified by “journalists” in the “media” we now recognize are mostly just wannabe influencers playing pundit drumming up clicks. * "4 out of 5 dentists agree" except it's more like the 50th dentist, given research consensus
- stephen_g 2y ago
  With HPV, the Government here (Australia) partially funded the research that led to an HPV vaccine (Gardisil) that helps prevent a bunch of cancers and now all school children here get it for free... So it does happen, just slowly...
glitchcrab 2y ago
Almost certainly, but you're forgetting one thing - hindsight. We can look back a hundred years from today and say that treatments back then were very misguided (and possibly even barbaric). Knowledge and science advance with time.

modeless 2y ago

This is an excellent article. Too many people believe that kids getting colds will help their immune system get stronger. In reality, getting sick is almost never beneficial. The information about the hygiene hypothesis and how it is really more about "old friends" is also very important and not widely understood. Many don't know about the hygiene hypothesis at all and those who do usually interpret it incorrectly.

nradov 2y ago
Kids getting colds allows them to develop immunity to some of the hundreds of endemic upper respiratory viruses that constantly circulate throughout the human population. They're going to get infected with many of them sooner or later, so better to get it over with sooner. This protects them later in life when their immune systems are less effective.
- francisofascii 2y ago
  Yeah, but many of the viruses mutate rapidly, so the immunity gained from a cold virus from years ago won't help much today.
- jph00 2y ago
  I haven't seen any research to support that contention -- rather, everything I've seen suggests you don't get coronaviruses like colds once off, so you don't "get it over with". Instead, they can weaken your immune system and these viruses can stay around for years, as discussed in the article.
  - nradov 2y ago
    The article is a mix of half-truths and speculation with a few random facts sprinkled in. It doesn't represent any sort of scientific consensus. Don't take it too seriously. Infections with typical rhinoviruses and coronaviruses build adaptive immunity to those viruses (as well as those that are genetically similar). This typically reduces the severity of subsequent infections. They didn't stay around for years. When we talk about things that "strengthen" or "weaken" the immune system that's really an oversimplification. There's a lot more going on in the complete system.

Nasrudith 2y ago

Similar to the "old friends" theory, I personally thought the issue with allergies and parasites suppressing allergies as a "calibration issue". Where evolution effectively set the dominant immune-systems to what would be hypersensitive in an environment without parasites order to compensate for parasites immuno-suppressing to protect themselves. Sort of like how sickle cell anemia genes were selected for its malaria resistance, in spite of how bad it is to be born with two copies of the gene.

SoftTalker 2y ago

> Comparing the immune system to a muscle that gets stronger with use is overly simplistic and, in many cases, inaccurate. But a vaccine does something analogous: it "exercises" the immune system (hopefully harmlessly) to strengthen it for when real pathogens are encountered. So between vaccines, and natural immunities developed by exposure to and recovering from a disease, the "getting stronger with use" comparison is generally correct.

bink 2y ago
But it isn't the "exercising" of the immune system that provides the benefit, it's training it to recognize a new virus. If that could be done without a huge immune response it would be just as effective. The immune system isn't any stronger after a vaccination, it's just smarter. Presumably exposing the immune system to several unrelated viruses provides no benefits as to how it can deal with the target virus.
- dudeofea 2y ago
  unlikely you could achieve that given that vaccine manufacturers purposely add adjuvants to annoy your immune system to in turn create a stronger immune response for higher antibody titers, which last longer. https://www.sciencedirect.com/topics/medicine-and-dentistry/vaccine-adjuvant https://www.sciencedirect.com/topics/medicine-and-dentistry/...

alecst 2y ago

I guess I'm cool coming out and saying it. Out of curiosity I bought some helminths online and infected myself. I was inspired to do it after reading a book called An Epidemic of Absence. I can't say a whole lot -- positive or negative -- came from it, but it was easy to do and inexpensive. So even though the article says you shouldn't try it at home, I did. I consider it safe. I'm not a doctor, I just read a lot of PubMed, so take that for what it's worth.

BlueTemplar 2y ago

Why would this co-evolution history with parasites have only started with Homo Sapiens ?

jmull 2y ago
It wouldn't and I don't think they are really trying to say that it did. It's just that you have to start your analysis somewhere, and, obviously, our own evolutionary branch (i.e. homo sapiens) is the most relevant.

pazimzadeh 2y ago

The Old Friends hypothesis doesn't make a ton of sense to me. Viruses did not come around much later than bacteria and parasites, and definitely before the adaptive immune system. Bacterial viruses may have been involved in the evolution of nuclei https://nyaspubs.onlinelibrary.wiley.com/doi/full/10.1111/j.1749-6632.2009.04994.x https://nyaspubs.onlinelibrary.wiley.com/doi/full/10.1111/j.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infected the gametes of our fishy ancestors https://www.nature.com/articles/29457 https://www.nature.com/articles/29457 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686171/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2686171/ More likely is that there is a critical time window during the development of the immune system when it is trained not to react to most bacteria (which are passed on from the mother's vaginal microbiota and harmed by cesarian sections and early antibiotic use). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904599/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6904599/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464665/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464665/ There's more and more evidence that one person's commensal bacteria can be someone else's pathogen, and that we should really think about it as a "lock and key" with your immune system rather than categorizing bacteria as inherently good or bad. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300855/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5300855/ Another rarely mentioned complication though is that the successful immune response itself likely selects for more pathogenic microbes. https://pubmed.ncbi.nlm.nih.gov/15539148/ https://pubmed.ncbi.nlm.nih.gov/15539148/ Removing selective pressure from pathogens can actually lead to less virulent strains. https://pubmed.ncbi.nlm.nih.gov/30100182/ https://pubmed.ncbi.nlm.nih.gov/30100182/ That may be why the body spends considerable resources feeding the microbiota at a slow pace using by secreting mucus which contains a large amount of sugars, but which are attached using an extreme amount of diverse linkages so that one bacteria cannot sweep the field and take over. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1134114/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1134114/ https://www.nature.com/articles/s41522-023-00468-3 https://www.nature.com/articles/s41522-023-00468-3 You cannot really withhold food from bacteria, they will just eat you. But if you give them a slow trickle of sugar, you remove their reason to invade you (which is is at a risk to themselves). I personally think this concept can be applied to wars and immigration, but anyway.. Why are viruses more likely to cause autoimmune diseases than parasites? Probably because viruses go inside us and set of (Th1) intracellular responses , whereas parasites set of extracellular responses (Th2). You're probably more likely to be tricked into attacking yourself when you are fighting off something inside yourself than something outside your cells.

cjbgkagh 2y ago

Very much disagree with the implication that helminths will help very much for these conditions. While not a commonly known treatment in the 'medical sphere' it's is very commonly known in the 'patient community spheres' and from the patient run studies it does not appear to have a particularly strong effect. It does appear to help some people so it's hard to rule it out but that could easily be noise. Those who did report a benefit were most often in the less impaired category and those same people tend to benefit from a wide variety of treatments that are generally ineffective on those of use who are more impaired. This post reads like someone who has just discovered the world of ME/CFS/LongCovid (post viral) /ToxicMold/POTs/SIBO/IBS/Lymes/hEDS/Graves/Hashimotos/MS/Lupus etc. etc. As a lifer I have seen many people enter the space and go through this exact same early stage of discovery. What I really think it is; it's genetic, various types of generalized anxiety disorders with their associated auto-immune conditions with the most common being Hypermobile Ehlers Danlos. These genetic predispositions are made worse by diet and lifestyles and triggered by all manner of stressors. On how to treat it, Low Dose Naltrexone is a good step one, then meds for dysautonomia, TUDCA, 3,3′-diindolylmethane (DIM), and then finally I think Low Dose Semaglutide < 0.1mg per week is going to be huge for auto-immune. It's early stages but few things have appeared more promising in the patient community. It worked wonders for me and a few other people I know. Everyone is different but those are in my opinion a good place to for someone starting. Helminths did not work for me the several times I tried it and have not worked for anyone that I have personally known that has tried it which to date is around ~10pp. But I do believe the people who do say it has worked for them but I don't count them unless I knew them prior due to the issue of selection criteria biases.

jph00 2y ago
But the article isn’t implying that. In fact it explicitly says that helminths can be dangerous.
pazimzadeh 2y ago
The Th1 program in a T-helper cell suppresses the Th2 response, and vice versa. https://en.wikipedia.org/wiki/T_helper_cell#Th1/Th2_model https://en.wikipedia.org/wiki/T_helper_cell#Th1/Th2_model Although it's way more complicated than that and there are exceptions, but it's still a real phenomenon. Community deworming increases Th1 cytokines https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098677/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098677/ When you administer helminths to yourself there is no guarantee that they are going to the right spot in your body, etc. which explains why everyone responds differently.

Terr_ 2y ago

> Some people compare the immune system to a muscle To reiterate something from a recent discussion on air purifiers [0], if your body is a civilization of cells then activating the adaptive immune system is like unleashing Skynet [1] to stop a potential zombie apocalypse. Even if Skynet reliably wins, you're losing at least a few cities as glowing craters, and each time you're rolling the dice hoping that not too many of the murder-bots go rogue before you can make them self-destruct or go back into storage. You definitely do not want to slam that big red button just because of one police report of a human biting another human, or a report that a bunch of people with green skin are marching down the road, etc. As we studying the adaptive immune system, we keep discovering safety-interlocks and subtle feedback loops, which presumably evolved because our relatives without them simply tore themselves apart a bit too often. [0] https://news.ycombinator.com/item?id=41347868#41348890 https://news.ycombinator.com/item?id=41347868#41348890 [1] https://en.wikipedia.org/wiki/Skynet_(Terminator) https://en.wikipedia.org/wiki/Skynet_(Terminator)

pella 2y ago

I prefer the antifragile metaphor. "The immune system is an example of antifragility in the natural world since an effective response is only produced in the presence of an antigen threat, but the response leaves the body better able to respond in future. The presence of an antigen activates the immune response, which not only deals with the immediate challenge through the innate immune system in the short term and long term through the adaptive immune system but also provides ongoing protection against this and similar future threats through the immunological memory of B cells. In other words, exposure to an invading antigen leaves the body stronger than before, so the stressor has created a benefit that was neither present nor possible before it occurred." read more: "Beyond resilience: towards antifragility?" https://scholar.google.com/scholar?cluster=13108278257209181454 https://scholar.google.com/scholar?cluster=13108278257209181... ------ And see the -> https://en.wikipedia.org/wiki/Variolation https://en.wikipedia.org/wiki/Variolation "Variolation was the method of inoculation first used to immunize individuals against smallpox (Variola) with material taken from a patient or a recently variolated individual, in the hope that a mild, but protective, infection would result. Only 1–2% of those variolated died from the intentional infection compared to 30% who contracted smallpox naturally. Variolation is no longer used today. It was replaced by the smallpox vaccine, a safer alternative. This in turn led to the development of the many vaccines now available against other diseases."

highfrequency 2y ago

Wow - meningitis lowers IQ by 5 points

incanus77 2y ago
Bacterial does, viral does not appear to. I am a survivor of bacterial meningitis and sepsis at eight months and fortunately do not experience any known side effects. However, the IQ effect is sobering.

HarHarVeryFunny 2y ago

So, drop food on kitchen floor - pick it up and eat it (without washing) good or bad?

giraffe_lady 2y ago
Other than norovirus and salmonella most foodborne illness isn't infection, it's intoxication from metabolic byproducts that need time to accumulate to sufficient levels. The biggest risk here is either a chemical contaminant from a non-foodsafe cleaning product on your floor, or a physical one like a small shard of broken glass sticking to it.

prologist11 2y ago

It's actually a lot more interesting than what the article explains here. The immune system essentially goes through a process of hypermutation and can be compared to a hashmap which is populated during the first few years of one's life. After that the hashmap is essentially frozen. This is why early immunization is very important because being exposed to mild pathogens when young helps one's immune system recognize and deal with similar pathogens later in life. The immune system only gets worse over time which is why eventually most viral infections overwhelm the immune system and either cause death or cancer.

Temporary_31337 2y ago
That eventually can be over 100 years sometimes? Can you point to some research about immunity being much stronger acquired early on? For some vaccines boosters are needed anyway.
- prologist11 2y ago
  Here you go: https://meshb.nlm.nih.gov/record/ui?name=Immunoglobulin+somatic+hypermutation https://meshb.nlm.nih.gov/record/ui?name=Immunoglobulin+soma...

Anitalawson 2y ago

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pollies 2y ago

[flagged]

tim333 2y ago

>Our immune systems evolved for a different world (that didn’t involve 100,000 global flights per day). Googling how it was then: >Around 12,000 years ago and earlier, life expectancy was about 33 years. Infections, such as diarrheal diseases that led to starvation and dehydration, were the leading cause of death, accounting for about 75% of deaths. so the modern stuff is not so bad really.