UKC

Came across an interesting theory recently that I can't stop thinking about. I don't believe this is proven, rather it is just a theory, but I suspect it to be true.

So the theory goes:

• For millions of years we had worms.
• Our immune system evolved to attack these worms.
• In response to this, worms evolved defences, one of which was a suppressant for our immune system.
• This begins the arms race. Since out bodies always had worms, they always had suppressants so our immune system become more aggressive.
• Then, in very recent times we decided that drinking worm infested water wasn't a great thing to do so we now don't have worms or their suppressants, but we still have the aggressive immune system that hasn't got any big Jim's to target.

I believe it's well established that an overactive immune system leads to inflammation which leads to cancer. I've not heard the worms theory linked to cancer, more that it's linked to allergies, but I suspect cancer also.

The other theory (or maybe it's well established fact now, not sure) is that your body wants to burn a set amount of calories a day, and if you lounge about, it wastes that energy on your immune system which I suspect compounds the above.

My hope is that the clever people in white coats will prove this to be true, and create a drug that emulates the suppressants of worms so we can exist in our man made world without some of the negatives.

Until then, my conclusion is to exercise as much as you can in a healthy way. I'll be honest I want that to be the conclusion but I think if I try not to be biased I still come to the same conclusion.

Anyway, thought it was interesting.

In reply to montyjohn:

Rather than exercising all the time couldn’t you simply swallow a tapeworm as Micheal Mosley did? That might work for you.

https://www.bbc.co.uk/news/science-environment-25968755

“While that idea may seem absurd, there is growing evidence that parasites may have health benefits in certain cases.

They are being considered as treatments for allergies and auto-immune diseases, as they appear to dampen the body's inflammatory responses.”

In reply to montyjohn:

Just eat dirt. Sorted. 

In reply to Wimlands:

I don't think I want a tapeworm. 

In reply to montyjohn:

This has some elements of truth:

Chronic infections with some intestinal helminth parasites can have beneficial effects, including suppressing some parts of the immune system that are implicated in allergies and inflammatory disease. 

However, it should also be noted that infections with intestinal parasites are a double-edged sword. They are, ultimately, parasites and can be dangerous as well as beneficial. Specifically, the response to a parasite can depend on many external factors including whether the infection is chronic or acute, the parasite burden (how many you have), what kind of worm it is, co-infections/microbiome (what other organisms, whether classified as infectious or commensal you are carrying), genetic predispositions towards particular types of immune response and immunosuppression.

While epidemiological studies do repeatedly highlight correlations between some helminth infections and reductions in immunology and inflammatory disease, the factors highlighted in my previous paragraph in combination with the complexity of the immune system make it quite difficult to establish causality or a simple mechanism. As a result of this, safe treatments based on this notion are some way off. I cannot recommend dosing yourself with worms either...

Here is a review article about this subject - it's a few years old now, but quite detailed: https://pmc.ncbi.nlm.nih.gov/articles/PMC6585781/ 

To the best of my knowledge, no-one has ever demonstrated a negative correlation between helminth infections and cancer. However, infections with some helminths are actually known to cause certain kinds of cancer: https://pmc.ncbi.nlm.nih.gov/articles/PMC4657143/

Lack of physical activity is indeed linked to some types of cancer. I have never heard your particular theory for the mechanism before - in scientific literature most studies are epidemiological and focus on establishing the link rather than understanding the mechanism so I'm having diffculty finding many papers that propose mechanisms. Regardless of the mechanism, regular healthy exercise is good!

In reply to montyjohn:

I believe they are pretty easy to get rid of. Many people imagine they are a several metre long wriggling worm. In fact in our gut they are completely immotile, despite the old joke about enticing them out with the offer of food.

In reply to kathrync:

Excellent - I was really hoping you’d be along to explain the Th1/Th2 thing so I didn’t have to!

In reply to Dave Garnett:

Ha, I wasn't planning on going into that much detail on this occasion!

In reply to kathrync:

I hope my OP doesn't suggest this as a possible solution.

What would be great is if causality can be proven one day, as this would open the door to trying to find ways of replicating having worms, without actually having the worms.

I'm generally not in favour of unnecessary medical interventions. But in a way, our hygienic lifestyle is a medical intervention. Albeit it a fairly necessary one. And as most medical intervention it may have some negative unintended consequences. I guess this is the problem with an immune system that's tuned by trial and error rather than a great design. Change anything, and it might break. A bit like software written by AI. Very temperamental at the moment.

This connection is of my own making, but I'm struggling to see why it's not a reasonable conclusion to make that the overactive immune system due to a lack of warms increases risk of cancer. 

My post is at 6 downvotes so far. I wonder which bit people are objecting to as I thought it was an interesting topic and I can't wait for more information on this as it becomes available. 

In reply to montyjohn:

This would certainly explain why populations who don’t have access to clean drinking water live so long. 

In reply to Thugitty Jugitty:

Don't worry, your sarcasm wasn't lost on me, but just to respond to it anyway, here's the global food anaphylaxis cases. 

https://www.researchgate.net/figure/Global-maps-showing-variations-in-the-r...

Before learning about these pesky worms and how they may have had a hand in developed our immune system, I would have assumed this was just down to the quality of the reporting, but maybe not? Maybe drinking water hygiene is a significant contributing factor here?

Similar result form cancer cases

https://gco.iarc.fr/today/en/dataviz/maps-heatmap?mode=population

I'm aware of the causation and correlation traps that many of us fall into and this is a multi faceted problem, but them a hypothesis aligns with the outcomes, it becomes very interesting.

In reply to montyjohn:

No...but there were others on the thread suggesting this!

In reply to montyjohn:

Are you considering investing in Europe's largest worm farm? (with apologies to Blackadder)

In reply to montyjohn:

I didn't dislike the post, for the record, but I suspect the dislikes are coming because there are an awful lot of people pushing bad theories and advice about health and medicine right now*, and your post is veering a little bit in that direction. What you're proposing is an interesting hypothesis, nothing more than that. It's not completely implausible or ridiculous, but there's no strong evidence for it. But you still suggest that you believe it and then give out advice based on it.

Granted, the only specific advice you actually give is to do healthy amounts of exercise, which is pretty uncontroversial advice for plenty of much better reasons. But you can see how, if this theory went viral, some people would conclude that getting a worm might be the easiest solution to their problems. Or some quack would start selling crushed essence of worm.

So I think your motivation was pure curiosity. And I don't think UKC is a particularly dangerous place to post this, because we're not highly trafficked enough to set off viral trends, we have genuine experts and critical thinkers to pour a bit of cold water on bad ideas, and I don't think anyone here is credulous enough to do anything stupid off the back of it. But it still sits uncomfortably close to an all-too-common genre of misinformation, and I suspect that's the source of the dislikes.

*See this BBC story from this morning, for example... https://www.bbc.co.uk/news/articles/c4gpz163vg2o

In reply to montyjohn:

I’m currently being treated for stage 3 prostate cancer and I’m sick and tired of having these views put to me. They are not “theories”, they are unproven hypotheses and more to the point dangerous bullshit. I agree with your last point advocating exercise. 

In reply to kevin stephens:

Sorry to hear about that. I truly am. 

It is an unproven hypotheses you're right, I hope I have been fairly clear about that, I'm here to talk about the science because I find it interesting. UKC is a great place to test your ideas. If they are flawed, somebody will say so. Usually pretty quickly.

And just to be clear, I would never suggest that anybody does anything dangerous. My suggestions have hopefully been the opposite.

Wish you all the best.

In reply to Luke90:

Just double checking my wording, I believe it's fairly clear that it isn't proven and the conclusion is my idea (albeit it a fairly obvious one, not smart enough to think of anything ground-breaking in this area).

Do we not all do this? You hear a hypothesis or a theory, and it's very hard not to decide if you think it's true or not. I would imagine this would be one of the challenges of research. Keeping those high level conclusions at bay so they don't interfere with your conclusions.

Just to be clear, I didn't give out any advice. Doing more exercise is my conclusion, acknowledging my own biases. That's not advice, although I understand why some may think it is.

It reminds me of something else I heard recently. It was to do with Alzheimer's disease and a bacteria that is found in the brain in higher numbers with Alzheimer's patients. As it happens, this is the same bacteria we get in your mouths for one of the gum diseases if we have poor oral hygiene.

There is absolutely no evidence that poor oral hygiene contributes to Alzheimer's disease but there is a link between the two. Might be relevant, might not be. Knowing that, I'm all in favour of putting more attention into oral hygiene just in case this turns out to be more than a just a correlation.

Again, not advice, just sharing my conclusion from limited information. If my conclusion happens to be a positive thing to do anyway, more reason to share the thought process.

In reply to Wimlands:

Dont read 'Irvine Welsh - Filth'!

In reply to montyjohn:

I believe you, and I genuinely don't think your post was unreasonable in this context. I'm just trying to explain why others might have disliked it. And I am obviously sympathetic to their concerns. Because there are so many people out there sharing unproven or actively false health information. Many of them are doing so innocently, and even most of the ones doing it maliciously or to make money often couch it in terms of "just sharing their own experience", "just asking questions", "it might not be true, but isn't it worth trying just in case" etc.

In reply to montyjohn:

Just put another jumper on (or speak to your energy provider if you're struggling)?

In reply to Luke90:

I do understand your point. But I find it a little sad that the pendulum seems to have now swung so far that it's difficult to discuss interesting* ideas on the internet.

For me that's the whole point of the internet.

* I probably shouldn't assume that this topic is interesting to others.

In reply to Lankyman:

Doh!

In reply to montyjohn:

There was a very interesting Horizon programme about 20 or so years ago looking into the links between allergies and the lack of gut parasites. As I remember it, they showed people with very bad hay fever and IBS who's symptoms stopped when they were infected with round worms. 

I watched it a number of times as I used to "entertain" some of my classes by showing sections...

In reply to Mark Kemball:

I had no idea this connection had been around so long.

By entertain do you mean torment?

In reply to kathrync:

Putting intestinal nasties to one side, I am aware some people who deliberately infect themselves with a specific parasitic nematode because they believe an immune suppressing protein it expresses helps them manage their arthritis.  There’s some interesting publications on this.  The protein requires nematode specific post-translational machinery to reach its functional form so it can’t be made in the usual systems like e.coli which slows down its study as a therapeutics.

Likewise I do not recommend anyone do this.  Then again it’s positively conservative to some of the whackadoodle stuff some people are doing in the personal biology experimental sphere these days…

In reply to wintertree:

I know! There was this Newton guy once shoving bloody great knitting needles behind his eyeballs. Can you believe it? What an idiot!

In reply to montyjohn:

Yes, they used to really squirm!

In reply to montyjohn:

Cheers, not sure why this garners quite so many dislikes.  Two observations: it's not a theory, its an hypothesis, which is a difference I would expect you to understand - but accept you're probably just applying common nomenclature.  The other thing is that your main citations is via researchgate.  This is not a peer reviewed journal, it's a dumping ground for a hotchpotch of stuff, some OK some crap (I've several papers on it myself).  Some people like to cite stuff on researchgate as if it was on par with IEEE or BMJ papers.  It absolutely isn't.  Despite that, as someone with a cancer with a poor prognosis and survivability (quoted 17 months median, 2 years ago) due to issues related to autoimmune disorders, this isn't something I'd heard of before.  So interested to look into it.  Keeps me off the streets, at least! (Just as well given my WBC count). Thanks again.

In reply to Petrafied:

Sorry to hear about your prognosis. May you continue to to prove you're not a median statistic.

I'm glad to sparked some interest. That was my aim. If you stumble on any interesting nuggets let us know.

It was an unintended consequence keeping hooligans out of public view.

In reply to wintertree:

Yes, I personally know more than one person who has done this - however they are all people who study parasitic worms for a living and are fully aware of all the possible repercussions. One of these cases ended very badly, and all of the cases that I know of ultimately chose to treat themselves because they did not feel that the benefit was worth the risk.

One of these people still has his preserved tape worms in a jar in his office. They have names...

Once again, to reiterate  

In reply to montyjohn:

You really don't, at their head they have barbs/hooks to anchor themselves in the intestine, or they'd be passed out as excreta. https://www.researchgate.net/figure/Head-of-a-tapeworm-with-suckers-and-hoo...

Bits of hooks can break off now and again. Sometimes this happens inside the intestinal wall they're hooked into which is vascular and you can get this foreign object in your blood. Also tapeworm larvae can get in you blood too, this can all lead to cysts forming , which can be pretty much anywhere in your body like inside your eyes, brain (neurocysticercosis), liver. So convulsions blindness epileptic fits are possibilities.

~~~~~~~~~

Fascinating advances in cancer cause theory possibly being a toxic-combination of both genetic damage and inflammation. https://www.bbc.co.uk/news/health-62797777.amp

However the type of inflammation is a specific one (interleukin-1-beta), like breathing tiny carbon particles or eating nitrates in processed food and the immune system is explained to non medical people like me as being in separate compartments with various bits specialising in short term response, long term immunity, anti parasite etc etc and I don't see tapeworm and that as being obviously linked, but you'd be a selfish person not to test this for us after all these posts!

Absolutely fascinating stuff

In reply to montyjohn:

Actually penny-drop-moment:   my post is my own explanation to myself, if nitrates in processed meat increase the incidence of bowel cancer and the nitrates don't cause genetic damage then other things that affect the gut may increase or decrease cancel be it bowels or elsewhere. The tapeworm lives in the bowel so could be relevant.

Another digression the intestine can be considered our bodies biggest immune organ. It has the gatekeeper job to constantly sift and sort proteins to decide if they are something "nice" to allow to pass inside like nutrition, something "neutral" to keep in the bowel (don't pass in and don't attack)  or something "nasty" to attack (like salmonella or a tapeworm)

In reply to Luke90:

I think that's pretty much it. There's so much deliberate misinformation being spread, and too many people desperate to latch onto anything that fits their skewed view of reality. It's becoming a real threat to public health.

£20 million in advertising by showcasing the idiots. Nice work if you can get it, and don't have a conscience.

In reply to Petrafied:

(apologies for the tangent)

Researchgate isn't a journal but many of the papers posted there have been published in peer reviewed journals. I'm not sure without checking how many papers I have there but somewhere between a third & a half have been peer reviewed. The rest are either conference abstracts or 'grey literature' style reports for government or EU agencies.

In reply to montyjohn:

No.

• Some cancer is caused by smoking for example.
• The word "cancer" for tumours comes from Hippocrates, presumably when lack of worms wasn't an issue.

Can we blame some cancer and allergies on lack of worms?

Maybe.

The immune system also fights cancer. A suppressed immune system makes you more vulnerable to cancer.

So it's equally plausible to the medically ignorant like me that immunosuppressive impact of worms might cause fewer cancers due to an overactive immune system but more cancers overall.

Overall I'll go with modern hygiene because it means we live longer than our ancestors and we don't have 6-12 kids because we lose so many in childhood. 

In reply to montyjohn:

I seem to recall my sister, a coeliac, mentioning something told to her by a doctor about the autoimmune response usually triggered in sufferers by gluten being suppressed by the presence of a tapeworm. Also pregnancy, apparently.
But I think this was more an anecdotal observation on their part, not medical advice

In reply to montyjohn:

You might be correct. I've had worms, but I haven't had cancer. Ergo....

In reply to montyjohn:

The issues of possible increase in allergic conditions as a consequence of the anti-parasitic arm of the immune system being underutilised has been discussed for decades. Certainly possible.

In terms of cancer? Well you'd have to break it down a bit.

"I believe it's well established that an overactive immune system leads to inflammation" - generally true.

"inflammation {which} leads to cancer" - often associated, however "Inflammation" isn't a single thing. Cancers are often associated with Innate immune inflammation - the basic non-adaptive "primitive" part of the immune system - commonly for some cancers in response to toxin damage (alcohol/tobacco).

The adaptive immune system which you are referencing is a far more complex system, although it may use arms of the innate immune system at endpoint.

If you look at an autoimmune condition such as Rheumatoid arthritis there is an increase in cancer risk - partly in terms of haematological malignancy (over-revving the immune system causing increased turnover of immune system cells increasing cancer risk in the system) and some other solid cancers (most likely due to decreased immune surveillance associated with immune suppressive drugs).

So I don't think acquiring a tapeworm will significantly change your cancer risk - the usual advice of avoiding cancer promoting toxins such as tobacco, alcohol, processed meat, UV radiation etc .

...and given the way adaptive immune systems work a tapeworm won't cure your asthma either, whether neonatal helminth infections might decrease the risk is a different question. It would be difficult to get ethical approval for the study, but given the way healthcare scepticism is going there will probably be an unregulated study population recruited by some social media grifter coming our way soon!

In reply to montyjohn:

I've often wondered about this too. It's an interesting subject, and I'm surprised there are so many downvoters.

I'm not a white coated clever person by any stretch, but my very amateurish take on this is that the general principle of regular exposure to physical (and possibly mental) stressors often has a greater net benefit on health than it might otherwise have had. It is pretty certain that a non-mollycoddled life is a life significantly better lived in terms of maintaining a more robust constitution.

I think the microbiome, in symbiosis with the 100m neurones in the gut, must have evolved over 1000s of years of human existence to cope well with ingested stressors, including the presence of parasitic worms.

Suddenly modern life is clinically free of ingested stressors, yet we still retain the mechanisms to deal with them. Those evolved mechanisms have to go somewhere, to do something - and I think they awaken from this dormancy by inducing dysfunctional immune responses like asthma and allergic reactions, attacking bodily systems that they shouldn't be attacking at all.

I might be wrong here, but foods that are classed as 'healthy' are the ones that are able to stimulate these dormant mechanisms into action through mild stress, making us feel better than eating foods with sanitised nutritional value.

The upshot, in my opinion, is that stress is good - but only if that stress is familiar to our own bodily systems and analogous with the historic timeline of our own evolution.

In reply to AllanMac:

Not really, one of the truly beautiful aspects of the adaptive immune system is that it responds to and upregulates in the presence of specific pathogenic targets (and then will generally down-regulate in their absence). It is adaptive and responsive to the pathogenic environment faced by the individual. The risk of dysregulatory responses may well change given different challenges but it isn't a given.

Huge medical interest currently in the gut microbiome, which does seem very important, but even that will have fluctuated and adapted over human development as we moved between environments and diets.



 

In reply to AllanMac:

This sounds very much to me like "what doesn't kill you makes you stronger", which is sometimes true but is also often as not complete bollocks.

What is it that makes you pretty certain about this?  Intuition I guess?
The coat and the cleverness of a "white coated clever person" are irrelevant, what really matters is that what they have to say about this kind of thing isn't just what they reckon based on just sort of intuitively making it up as they go along.

In reply to deepsoup:

Homeopathy, yeah right

In reply to deepsoup:

I didn't say anything about certainty.

What I did say is that "My amateurish take on this.." "My opinion is..." "I may be wrong here..."

So yes, intuition I'm afraid, leavened with a pinch of what I do know to be true.

I find the all too common recycling of 'certainties' pretty boring, frankly. There has to be at least some "What if... " to make it interesting, and much of that has to do with intuition.

In reply to kinley2:

Interesting read. Thanks 

In reply to AllanMac:

About 10 years ago I always passed the microbiome off as some hippyish fad, but I've changed my tune on this after reading the reporting of study after study on how much of our systems are impacted by it.

I love these threads as you always learn something. One of which is how much hesitation there is by a large majority to engage with speculative theories. Which has come as a bit of a suprise as it's one of my favourite pass times.

My brother in law is similar to the response on this thread. We can't talk about what may be. He's not interested. Shuts down any conversation that can't be proven to be true. I find this really boring.

But then my mother in law (not related by blood to my brother in law) is the opposite. She'll find some whacko doctor who's written a book and change her whole lifestyle based on the whackos advice. She'll try and convince us all to do them same. Then move on to her next obsession.

There's a healthy middle ground. One that stimulates the mind but doesn't influence your life.

In reply to montyjohn:

Hardly surprising given the utter bollocks and genuinely harmful conspiracy theory that has been promulgated by those "just asking questions" and presenting their own half-baked theories on social media.  (And the extraordinary number of dodgy accounts that have popped up on here over the last few years to promote anti-vax and general conspiracy shite in bad faith.)

The general intolerance for that kind of nonsense on here is one of this forum's best features imo.

If you want to "stimulate the mind" by learning about the immune system or whatever, maybe try reading something about it first.  Then if you want you could post here with an interesting snippet (maybe even citing your source), or to ask the resident UKC boffins to clarify something you don't quite understand.  You'd probably get a much warmer reception for that than you would jumping straight in with some half-baked 'speculative' toss that you've just plucked out of the air.

In reply to elsewhere:

Some cancers.  The clearest correlations are with cancers caused by viruses (which is a minority, as far as we know).  For instance, Kaposi's sarcoma is caused by a herpesvirus and is strongly associated with the immunosuppression caused by AIDS.  Post-transplant immunosuppression is associated with a higher incidence of some cancers, some where infection (viral or bacterial) is implicated directly or indirectly - liver cancer, stomach cancer, lymphoproliferative disorders.  Others are not usually considered to be associated with infection (skin cancers, for instance).  Here, I guess the implication is that immune surveillance aborts many such tumours, which in turn suggests they display some new, targetable, tumour-specific marker.  Most, unfortunately don't.

The main reason more people develop cancer now is that they live longer, so (a) their cells divide more often and so are more likely to throw up a nasty combination of mutations, (b) they are exposed to environmental carcinogens for longer (see a), (c) more people with slow growing, non-aggressive tumours live long enough to be killed by them (prostate cancer, for example).  Add to that to the long-term effects of modern ultraprocessed diets.

In reply to Dave Garnett:

 

This is definitely true of some kinds of cancers that are not associated with viral infections. For example, after my Mum's kidney transplant, all the nascent skin cancers that her immune system had previously been controlling emerged. She had multiple basal and squamous cell carcinomas removed within the first year after she started immunosuppressive drugs - her dermatologist said this is extremely common in transplant recipients or other immunosuppressed patients who are old enough to have accumulated some sun damage.

She also ultimately died of post-transplant lymphoproliferative disorder, a form of lymphoma that is specific to solid-organ transplant recipients and is directly related to immunosuppression. As far as I know, this specific lymphoma does not have any known associations with infection.


 

In reply to kathrync:

Yes, as someone who has spent more time in the sun than is good for me (and had a cavalier disregard for hats and sunblock when I was young) I'm very aware of the risk as I get older.

I need to dig into this more.  A quick google raises more intriguing questions than it answers! 

In reply to deepsoup:

Where do you think the information from my original post came from? I didn't just happen to correctly guess that the immune system attacks worms, that the worms suppress our immune system, that the absence of worms may therefore increase risk of allergies and that the immune system causes inflammation and that inflammation can lead the cancer.

I haven't made it up. What I have done is speculate how some of it might link together in a fairly obvious way whilst making it clear what's my own thoughts.

I don't believe UKC requires interesting thoughts and ideas to be fully researched and sourced before posting. It's just a forum.

I thought it was interesting. I didn't provide sources as I don't remember where or when I've learned many of the things in my original post. It's bits and bobs picked up over years as casual interest.

In reply to Dave Garnett:

I should add that PTLD is usually quite treatable. It responds well to monoclonal therapies precisely because it does have distinct markers, and it's not aggressive in the usual sense - it seems like it's more failure to control normal outgrowth than aggressive proliferative changes. 

In reply to AllanMac:

I thought the point you made was interesting and you made your uncertainties quite clear. Why it got such a rude response I’m not quite sure.  

In reply to Dan Arkle:

Which is what many of us did as kids as we were feral compared to today’s kids.

In reply to kathrync:

Having spent the last month treating a rabbit for a suspected case of E. Cuniculi, I "really" don't recommend picking up a parasite of any description, for any reason.

In reply to montyjohn:

How do cancer rates in 18-40 year olds compare now to the 1600s?

In reply to montyjohn:

What do you mean by inflammation?

In reply to montyjohn:

What do you consider cancer to be?

In reply to montyjohn:

I'm not sure I would have guessed this thread would end up being such a can of worms...

In reply to captain paranoia:

Worms everywhere 

In reply to Brass Nipples:

How can anyone know this?

In reply to montyjohn:

Interesting theory, but I guess the decision needs to be made - what are the pros and cons and where does the best benefit/least risk lie?

In reply to kathrync:

Not my specialist area, but aren't they nearly always B cell-originating and EBV+?

And please forgive my scientifically-driven prurience. I'm very sorry about what happened to your mum. 

In reply to montyjohn:

Well your assertion is that cancer rates have increased in similar age group populations as the incidence of internal worms / parasites was reduced. Thus you’d have to have some figures showing firstly a correlation. Then you’d have to move on from that to a causal relationship, that eliminates all the other confounders.  I don’t think your assertion shows any of these things.

We also have people called immune compromised, those with what we call normal immune function, and overactive immune systems. Not everyone has chronic inflammation or immune disfunction.  Chronic inflammation can arise from Chronic stress, nothing to do with worms. Are those with normal immune function and no chronic inflammation infested with worms?

Plus acute inflammation is good for us. It’s what makes us stronger and fitter, and also repairs tissue when damaged.  The immune system mops up and kills defective cells.  Cancer cells are trying to avoid the immune system, avoid being detected, avoid dying.  Dampen the immune system and those cells will almost certainly be even more rampant a cancer.
 

In reply to Dave Garnett:

No worries - she was my Mum and I miss her, but I am also a scientist and have the same degree of curiosity.

I believe that a B-cell origin is a pre-requisite for the diagnosis, although I am not a clinician and could have that incorrect.

Risk factors that I am aware of are:

• Certain types of immunosuppression or strong doses
• Pre-disposition towards IL-10 driven responses
• CMV mis-matching between donor and recipient in either direction
• EBV+ (donor, recipient or both)

I take back my comment about "no known link between PTLD and infection" since both CMV and EBV come under this category. In Mum's case, we know the donor was CMV-matched, and we know Mum was EBV- but we don't know the donor's EBV status. Mum was on one of the higher-risk immunosuppresive regimes. I can't comment on the second point, but she did have a number of autoimmune conditions so it's clear that she was somewhat immune-dysregulated. I don't know to what extent that would have been a factor.

In reply to Brass Nipples:

I don't know how anybody can get cancer rates from 400 years ago. The chances of having a cancer diagnosis back then would be close to zero I would think.

Instead we can look at cancer rates between developed and undeveloped countries as I linked earlier which do correlate with the hypothesis.

In terms of cancer and allergy rates vs time, there's a 1001 articles online that claim the rates of both are increasing with time, but this tends to be in more recent years which I expect would be more related to reporting and what we eat or lack of exercise? Are all these significantly exacerbated by not having worms, that's the question?

I think your expectations are a little too high of me to provide evidence to support my hypothesis. I've taken it as far as I can I'm afraid.

Is this know for a fact? If those people had worms would their chronic stress still result in inflammation? Perhaps less inflammation? Struggling to think of a non cruel way to test this but I don't I've not come across anything to rule it out.

In reply to montyjohn:

You seem to be wriggling around on this subject

In reply to montyjohn:

Yes, this is really the point. We  don't have good records from that time, but even if we did cancer was not well understood, was frequently misdiagnosed, and the mortality rate was such that many people died of something else before cancer killed them. The point is that there is a lot of stuff around (not just from you) about "increasing rates of cancer", but it's very hard to quantify that or to pick it apart from other confounding factors such as longer life expectancy, better screening and so on.

There is a correlation here, but it's confounded for exactly the same reasons I just described above. Sure, there are lower cancer rates in less well-developed countries. But there is also a shorter life expectancy and reduced screening, which likely results in under-diagnosis. You also can't link this directly to worms. I'm not denying that there is correlation, but it's also true that countries being compared this way generally have different ethnic makeups, different diets, different exercise levels, different forms of housing, different average family sizes, different environmental contaminants and so on. Any one of those things and a whole lot more could ALSO correlate with different cancer rates between developed and less developed countries. The most likely truth is that all of them have small additive affects rather than one specific thing being the answer.
 

There is a whole load of peer-reviewed scientific literature related to this (not just your paragraph above, but this whole conversation) that is in the public domain and that anyone can access. I linked to two papers in my original response to this thread. Those in turn will link to a lot more papers, and those in turn to more. They are not all in the public domain, but many are. You can also find papers using a regular search engine, or if you want to be more specific about restricting your output to peer-reviewed literature you can try the PubMed search engine. I suggest getting stuck into some of this - it describes experimental evidence rather than conjecture. However, that doesn't mean that you don't have to be critical as you read it...

Inflammation is a very complex thing. Under certain circumstances, infections with worms can reduce certain types of inflammation in certain parts of your body. It certainly doesn't stop all inflammation. As others have said, in the right context inflammation is a good thing - if there were no inflammation, you would be unable to respond to minor infections or to heal wounds. 

In reply to montyjohn:

As a counterpoint I give you the dead bear accident faking, whale chainsawing, anti-vax nut job RFK Junior and his pet brain worm.

In reply to montyjohn:

This short video has a great take on the subject https://m.youtube.com/watch?v=Pqt4yBWkLI8#menu