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Your Immune System Is Not a Muscle

rachel.fast.ai

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Re: Your Immune System Is Not a Muscle

#51

Post by throwup238 »

pazimzadeh wrote: post #47

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.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infecte…

> 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, so why aren't there "commensal viruses" which fight off parasites for us?

Viruses are even harder to study than bacteria, which are already very difficult because most of them can't be cultured in a lab [1], so we just haven't studied them that much. It's a lot easier to study viruses that cause a disease because we know what to look for. The gut virome [2] alone is likely to contain a lot of commensal viruses that help us fight off parasites but our understanding is in its infancy.

[1] https://en.wikipedia.org/wiki/Microbial_dark_matter

[2] https://www.thelancet.com/journals/ebiom/article/PIIS2352-39...

Re: Your Immune System Is Not a Muscle

#52

Post by modeless »

pazimzadeh wrote: post #47

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.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infecte…

The "old friends" hypothesis is not that parasites evolved to be beneficial to us. They're not literally our friends, that's why "old friends" is in scare quotes. It's that the immune system evolved in an environment where parasites were omnipresent, and it malfunctions in an environment where they are entirely absent.

For example, the IgE protein present in peanut allergy is part of the parasite-fighting machinery of the immune system. It's not supposed to be reacting to food. But when there are no parasites to fight, it doesn't just become dormant as we would like.

Re: Your Immune System Is Not a Muscle

#53

Post by abracadaniel »

evrydayhustling wrote: post #6

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…

Chicken pox also returns as shingles in adulthood if you got the actual virus instead of the vaccine.

Re: Your Immune System Is Not a Muscle

#54

Post by pazimzadeh »

throwup238 wrote: post #51
pazimzadeh wrote: post #47

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.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infecte…

> 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, so why aren't there "commensal viruses" which fight off parasites for us? Viruses are even harder to study than bacteria, which are already very difficult because most of them can't be cultured in a lab [1], so we just haven't studied the…

Sorry I edited my comment before I saw your response. I agree in general, and we may find commensal viruses. It's not crucial to the argument though so I removed it.

Re: Your Immune System Is Not a Muscle

#55

Post by legohead »

ifyoubuildit wrote: post #21
legohead wrote: post #11

Earlier quoted context omitted.

I became allergic to Yellow 6 randomly. I would get extreme abdominal pain, even went to the ER a couple times and got a CT scan once due to the severity of the pain. I broke out in hives, tongue would swell, etc. I eventually figured it out after having a reaction to Cheese Doritos but not Cool Ranch (the only ingredient difference was Yellow 6). I tested it on some other foods with Yellow 6 and confirmed it. So I s…

I have a hypothesis based on my own experiences that this can happen from accumulating something in the body faster than it can be cleared. Could you have been continuously ingesting yellow 6 for a while, to the point that it crossed some threshold?

I wasn't ingesting it any more than a regular person -- but I was surprised to find out how many foods use Yellow 6. It's more orange than yellow. It's also banned in several countries. It used to be in Kraft Mac and Cheese but they replaced their artificial colors with natural ones, which is nice.

One thing I wondered while being allergic to it, was how much could I take before triggering the reaction. It ended up being extremely little. A single dorito chip would set it off. After that, I just cut it out of my diet completely.

Another weird thing is the reaction would last about 45 minutes exactly every time. I'd be sitting on the toilet bent over in agony, watching the clock.

Re: Your Immune System Is Not a Muscle

#56

Post by Aurornis »

klysm wrote: post #23
lkrubner wrote: post #17

Earlier quoted context omitted.

Sad to say, the fecal-oral cycle of infection remains common in the USA, with the most common areas of spread being restaurants although hospitals were sadly guilty of this until recently. And for any gastrointestinal illness in the USA, the single most common cause is Helicobacter pylori. Back in the 1980s and 1990s researchers mostly associated Helicobacter pylori with ulcers, but since then the research has expand…

Unfortunately, antibiotics can fuck up your gut in other ways.

On the other hand, we're discovering that certain antibiotics can be very useful in treating specific GI conditions.

Rifaximin, and antibiotic designed to stay in your gut, has been approved for treating specific types of IBS. When it works it can induce remission for months or longer.

Re: Your Immune System Is Not a Muscle

#57

Post by pazimzadeh »

modeless wrote: post #52
pazimzadeh wrote: post #47

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.... The adaptive immune system of jawed vertebrates itself probably wouldn't be around if a virus hadn't infecte…

The "old friends" hypothesis is not that parasites evolved to be beneficial to us. They're not literally our friends, that's why "old friends" is in scare quotes. It's that the immune system evolved in an environment where parasites were omnipresent, and it malfunctions in an environment where they are entirely absent. For example, the IgE protein present in peanut allergy is part of the parasite-fighting machinery o…

I don't disagree with that.

However the original article talks about 'peaceful' commensals and links to this post (https://rachel.fast.ai/posts/2024-04-25-microbiome-1/), with the example that "friendly" microbes may not trigger your immune system if they leak into your bloodstream because they 'look similar' to your pancreatic cells.

While critical during the development of the immune system, this idea that there are certain actually 'friendly' or peaceful bacteria is less and less supported by the literature, and overstated to the point of probably being harmful. Even probiotic strains can be harmful if your immune system is overloaded or incapacitated.

Strong immune avoidance or induction of tolerance outside of the critical window is a strategy often used by pathogens to escape host defenses.

Re: Your Immune System Is Not a Muscle

#58

Post by legohead »

newaccount74 wrote: post #28
ifyoubuildit wrote: post #21

Earlier quoted context omitted.

I have a hypothesis based on my own experiences that this can happen from accumulating something in the body faster than it can be cleared. Could you have been continuously ingesting yellow 6 for a while, to the point that it crossed some threshold?

Allergies seem to come and go. My partner developed allergies against many local fruits in her early twenties, to the point where she could barely eat any fresh fruits without her lips and throat swelling up; but most of them subsided in her 30ies and she can now eat almost all fruits again with only minor irritations for some.

You ever get that itch in the roof of your mouth, and you use your tongue to kind of scrape/scratch the roof of your mouth? After I started paying attention to food allergies from this Yellow 6 thing, I noticed I would get this mouth-itch from certain fruits and nuts. Watermelon, almonds, and oranges. Super minor in the grand scheme of things, but never knew this itch was due to an allergy -- just thought it happened randomly. That is one thing that has yet to go away, but I can live with it at least.

Re: Your Immune System Is Not a Muscle

#59

Post by cjbgkagh »

hollerith wrote: post #27
klysm wrote: post #23

Earlier quoted context omitted.

Unfortunately, antibiotics can fuck up your gut in other ways.

Most people can take 14 days of an oral antibiotic without significant long-term adverse consequences. As of 15 years ago, according to my doctor, while on the antibiotic, sacchromyces boulardi is the best probiotic to take to try to minimize the risk of adverse consequences.

Both can be true, antibiotics can cause substantial side effects in some people and most people will be fine. Still sucks if you are not one of those most people.

Re: Your Immune System Is Not a Muscle

#60

Post by renegade-otter »

lkrubner wrote: post #17
Xcelerate wrote: post #4

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…

Sad to say, the fecal-oral cycle of infection remains common in the USA, with the most common areas of spread being restaurants although hospitals were sadly guilty of this until recently. And for any gastrointestinal illness in the USA, the single most common cause is Helicobacter pylori. Back in the 1980s and 1990s researchers mostly associated Helicobacter pylori with ulcers, but since then the research has expand…

The one thing that shocked me after moving to the States was how no one washed their hands before meals. It's just not a thing.
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