The Causes of Long Covid

https://www.science.org/content/blog-post/causes-long-covid

by maxall4 • 2 months ago

169 77 2 months ago

prh82• 2 months ago

Sadly, no mention of Mast Cell Activation Syndrome, or even mast cells at all

sebasv_2• 2 months ago

This is a blog on the root cause. MCAS would be an intermediate mechanism in making you feel sick, but something must have triggered the MCAS. Thats the autoimmune response.

prh82• 2 months ago

MCAS is the underlying condition, which is then triggered by a Covid infection. This results in an escalation of baseline symptoms, which is what Long Covid is

Matticus_Rex• 2 months ago

It'd have been interesting for them to discuss it, but from what I understand it looks like MCAS is probably an entirely separate thing (that can also be triggered by COVID), but because of the overlap in symptoms, many people who assumed they have long COVID actually had MCAS. And even after teasing those two out, there may be more conditions in the long COVID bucket.

And of course people can have both.

sebasv_2• 2 months ago

I am really grateful to see this still gets attention.

deminature2• 2 months ago

I caught this in the Dec 2023/Jan 2024 Covid wave, in a densely-packed Bay Area tech office. I only returned to near-full mental clarity in Jan 2026 - two years later. It's an insidious illness that needs more visibility. Poorly ventilated offices full of sick colleagues in close proximity are ideal conditions for transmitting airborne diseases, and it's far too easy to develop a debilitating chronic illness this way. There should be minimum clean-air standards for open offices to protect workers.

lend0005• 2 months ago

I had a long process with this that mostly manifested as exercise intolerance and general inflammation/discomfort, and sleep struggles. I made no progress for 2 years, lost most of my muscle (I had been very active before) and started thinking "is this how it's going to be forever?". After not finding anything promising from traditional medicine or supplements, I finally made some dramatic life changes. I'm fully past it now (with persistent lifestyle changes), but I really had to rethink my relationship with food.

Ended up doing a paleo diet, avoiding stressors (some of which are not obvious like just being on your phone scrolling, bad posture/circulation/sitting for too long), improving sleep hygiene, and ramping up consistent cardio exercise, with an emphasis on getting up to 4x/week zone 5 cardio without triggering intolerance.

Since then I've discovered a lot of other things that are great for overall health, like HRV-reset breathing and long-duration water fasts (around 3 days is optimal for me). I imagine those would have been very helpful if I had tried them earlier. A water fast is a complete metabolic and inflammatory reset of the body, and it's not as hard as you might think.

Hopefully most affected folks have recovered and are living normal lives by now, but if not, there are things you can do! It seems like the more challenging those things are, the more efficacious.

stringfood• 2 months ago

A non-inflammatory rocket shock diet can certainly aid in symptoms of long covid in many users, often people megadose on antioxidants to dilate their recovery window and not regress. Glad to hear you are feeling better and I totally agree that movement and diet are key in recovering from inflammatory disease.

nurettin• 2 months ago

What do you mean by water fasting? Do you avoid drinking water directly, or do you avoid all food? For example salads are basically sacks of water.

empressplay• 2 months ago

no you only consume water

mpreda• 2 months ago

Water fast is when the only intake is water (plus electrolites and vitamines). Basically "eat nothing".

_nalply• 2 months ago

How do you manage zone 5 cardio 4x a week without PEM?

I thought up to 3x a week and never consecutive days is the maximum.

lend0005• 2 months ago

Zone 5 is usually 1-2 minutes out of a longer 30 minute cardio session for me, I do it as a final sprint. I am not talking about repeated hill sprints where you would get 10+ minutes of zone 5 cardio in a session, which I agree would not be something a normal person should do 4x/week.

From my own experience, it seems like hitting that Zone 5 briefly is a good nervous system reset (overrides any dysfunctional breathing and heart rate effects from long covid); it's less about training the heart, although that's an excellent side effect.

Cloonic• 2 months ago

How do you prepare/deal through a water fast? What kind of supplemens would be needed for the water?

Can I read up on this anywhere? I'd welcome a suggestion over surfing the many many pages I found through a simple search. A book or paper reccomendation to read up on would be nice as well

lend0005• 2 months ago

Honestly AI overviews are a pretty good guide, ask about a 3-5 day water fast. I was nervous going into my first one, but now I don't worry about it. The main thing is to drink a lot of water and have 1-3 LMNT electrolyte packs (unflavored, no sugar) per day, depending on how much you're sweating/exercising (which you absolutely can do, especially the first 2 days).

You can expect to feel colder as your body doesn't conserve as much heat, and after ~2 days more lethargic physically, but your mental energy may actually be higher. I don't sleep as well when fasting, so 3 nights is about my limit. That being said, you feel rested on less sleep, because your body is probably producing a lot less waste.

e12e• 2 months ago

I'm happy you got better - but isn't healthy diet, moderate regular exercise and good sleep hygiene staples of traditional medicine?

lend0005• 2 months ago

Thanks. Unfortunately, not really, especially where diet is concerned. For example, I saw significant improvement after removing wheat, white rice, red meat, and dairy entirely, which is not something your typical US doctor would suggest. The first doctor I saw wanted to put me on antidepressants.

I also think exercise recommendations are generally too low, especially with respect to high intensity cardio.

brational• 2 months ago

Having gone through this too, I also had to accept that a lot (not all!) of it was in my head and made worse by it. When I convinced myself that “this will pass” and “this slow steady plan will get me out of this eventually” was when I finally saw regular progress (progress, not immediate relief).

lend0005• 2 months ago

There is absolutely truth to this.

neonstatic2• 2 months ago

It's amazing how powerful the mind is and it's also sad that the default setting is to use that power against oneself

Llamamoe• 2 months ago

I'm glad that this was the case for you, but presenting it as an universal truth is extremely cruel and harmful to people for whom it is not, and you should be really careful with phrasing. Statements like these is why people's symptoms are not being taken seriously.

smj-edison6• 2 months ago

Maybe a bit of a strange take, but after having dealt with chronic illness personally and talked with a lot of others with chronic illness, I don't think classifying chronic illness by symptoms will help with curing, and in fact I don't think categorizing works at all for chronic illness. We've been trying to classify chronic illnesses for so long, and yet in most cases no pattern emerges.

This has led me to conclude that perhaps in most cases chronic illness is an emergent behavior from a complex system, namely our body. Now tbh this is kind of a cheap take, because it's not that hard to conclude. But gosh darn it, we're programmers and we deal with complex systems all the time! What I want to see is a complete quantitative mapping of human metabolism, so that we can see all the in-between steps, not just the surface levels. That way curing chronic illness is more about comparing metabolite levels against known pathways and seeing what's regulated incorrectly. There's just not enough introspective capability currently.

My vision is some day a person who's been chronically ill can walk into a clinic, take a blood test, and with mass spectrometry get the level of the around 1800 different intermediate metabolites. That gets mapped to a known good metabolic graph, and it's optimized to find what in-between step is off kilter. They're then prescribed a drug that resets the bad state, and it 6 weeks they're back to normal.

I also doubt that AI will substantially help either. It still doesn't bring any more introspection capability, and if we can't figure out why someone is sick, I have little faith that a predictive AI can figure it out either.

_3u102• 2 months ago

You used to be able to order a paper version but here it is.

https://web.expasy.org/pathways/

smj-edison6• 2 months ago

Thanks for the link! I looked over it, but I'm not seeing quantitative levels of reactions. That's been my biggest issue with current pathway databases. It's great to know what's connected to what, but very quickly it becomes everything connected to everything. And unfortunately everything doesn't reduce the problem space.

_3u102• 2 months ago

Also, many people have cured chronic illnesses such as Crohn’s disease by moving to countries with low levels of those diseases.

smj-edison6• 2 months ago

Source? Never heard of this before.

rolisz2• 2 months ago

Welcome to alternative health :))) there are many functional doctors, and others who perform this kind of stuff.

For example Organic Acids in Urine Test gives you some 70-80 metabolic markers, which some folks interpret. There's no large scale RCTs or studies on this, so it's a bit dubious. But I did one and the practitioner correctly read the leaves to suggest some things that were missing and which helped me (glutathione and B1).

Aurornis2• 2 months ago

For example Organic Acids in Urine Test gives you some 70-80 metabolic markers, which some folks interpret.

The alternative medicine people use these tests because when you measure 80 different things you are almost guaranteed that some of them will come up high or low.

What they don’t explain is that many of them are expected to fluctuate and will show up with very different values on different days or depending on what you’ve eaten or when you’re taking the test.

They like it because they can tell you that you are too low in this thing and therefore you need to take this other supplement, every time someone takes the test.

For someone who isn’t getting answers from regular doctors it feels like a miracle that someone finally tested them, diagnosed them, and gave them something to take with a simple explanation of why it explains everything. This is the perfect recipe for placebo responses, which are common.

The forums are interesting to read because most people who do these and take the supplements will be very positive at first, but then over time they go back and take another test and find the results are completely different because it’s so random.

Organic acids tests are mostly only useful in the context of diagnosing specific genetic deficiencies which produce severe changes in the test results. The minor ups and downs that the alternative medicine people try to use are not diagnostic, especially with only a single test.

pas• 2 months ago

people are doing this for ME/CFS patients, and trying stuff, and ... it's not easy at all. But the signs at least are pointing toward something coherent.

Yes, it's many variants from a disease, but still, like cancer we can tackle them one by one.

https://www.youtube.com/watch?v=ldg2AdVnlOs

https://www.nature.com/articles/s41598-026-46965-1

If it would be easy already data from 2016 would have "solved" it, right?

https://www.pnas.org/doi/10.1073/pnas.1607571113

FionaZhu• 2 months ago

Maybe intermittent fasting could help treat it.

amelius• 2 months ago

Why are women far more likely to have long covid?

Earw0rm• 2 months ago

Perhaps because it involves immune system dysregulation.

defrost• 2 months ago

Are they though?

  The results follow a 2024 study led by Dr Mulu Woldegiorgis that surveyed 11,000 people from Western Australia three months after they contracted COVID-19. Almost one-in-five (18.2 per cent) had developed long COVID. The researchers then monitored the same group of people six months after their initial infection.  

  “We wanted to get a sense of the trajectory for people with long COVID. After six months, the average number of symptoms remained stable, indicating little improvement,” she said.

~ https://www.anu.edu.au/news/all-news/more-than-half-of-long-...

and from that study:

  In multivariable analyses, pre-existing health conditions at the time of initial SARS-CoV-2 infection and reporting fatigue, shortness of breath, and cough 3 months post-infection were independent predictors of persistent long COVID.

  Age, sex, and number of COVID vaccinations were not significantly associated with persistent long COVID.

~ https://www.cambridge.org/core/journals/epidemiology-and-inf...

smj-edison6• 2 months ago

I've heard things hypothesized to be either differences in hormone levels, or the one that's more fascinating to me is it could be because an issue came up with suppressing the second X chromezone.

deminature2• 2 months ago

The leading hypothesis is the same one that explains why women get more autoimmune disease generally. Women mount stronger immune responses than men - protective in acute infection (men had worse acute COVID outcomes), but it comes at a cost: women are the large majority of lupus, MS, Hashimoto's and RA cases. If long covid is substantially autoimmune/inflammatory, as the autoantibody findings in the OP article suggest, the group already primed for autoimmunity is the one you'd expect to be hit hardest. Proposed drivers: immune-regulating genes on the X chromosome (e.g. TLR7) and estrogen being immunostimulatory where testosterone is suppressive.

kranke15510• 2 months ago

Some speculation is the pill. Some kind of unmapped interaction.

timr7• 2 months ago

Before you can investigate the causes of an illness, you have to define it. Otherwise, you’re chasing an ever-shifting cloud of ambiguous symptoms, any of which could have different causes. The article opens with this admission, so I’m not stating anything new here.

The problem with “Long Covid” as it exists today is that there’s no such definition. Literally anyone who had Covid once and feels bad today (and quite a few people who never had a confirmed case at all) includes their set of symptoms in the communal diagnosis. Thus, if you dig into these studies, you always find that the syndrome is a wide-ranging and variable constellation of symptoms, making it impossible for a study to have any systematic legitimacy. Moreover, the results of any particular study are more strongly influenced by the inclusion criterion (if there even is one) than by any other factor.

It’s perfectly possible to evaluate treatments in this situation, and would be a better use of resources - pick symptoms, make an inclusion criteria, and run a randomized trial of existing drugs or therapies. But this is likely to fail, and it’s much, much easier to write papers with unprovable theories and retrospective analysis.

setopt• 2 months ago

Interesting. Someone should (or maybe have?) run a cluster analysis on the symptoms to define more specific subgroups. But I suppose getting access to the required health data at that scale is nontrivial?

timr7• 2 months ago

It’s not that hard to get a long list of symptoms for long covid. Just watch this thread as it grows, and you’ll easily find dozens. Things like this end up being a lint trap for people who just feel bad for whatever reason (which is all of us, at various points in our lives!) Nobody likes to be told that their symptoms are idiopathic.

Massaging this kind of data (clustering, etc.) is much lower value than finding fixed criteria that define a consistent group of patients who have objectively defined symptoms that cannot be more readily explained by another diagnosis. This is a pre-requisite for any further study. It can be done, but it’s hard, and it tends to lead to criticisms because you end up excluding a large number of people who fervently believe they have the illness, but don’t fit the objective standards.

Just for example: it’s not enough to claim that you have “brain fog”. A more valid endpoint might instead attempt to classify people based on standardized tests of thinking. Even that has problems, of course, but if you can just claim that you are fatigued and unable to think clearly, there’s a huge problem of confounding (i.e. maybe your symptoms are caused by something else), let alone the unverified nature of the original claim.

dyauspitr• 2 months ago

Sometimes the symptoms are so ambiguous that it is hard to nail anything down. It’s the same thing with Lymes disease, which is definitely a real thing, but there aren’t good, reliable tests for it. It takes a long time to manifest and the symptoms vary wildly from person to person.

kranke15510• 2 months ago

There are increasingly positive markers - autonomic dysfunction in previously healthy people, measurable small fiber neuropathy, and auto immune dysfunction in largely unmapped parts of the immune system.

Aurornis2• 2 months ago

It’s the same thing with Lymes disease, which is definitely a real thing, but there aren’t good, reliable tests for it

There are actually good, reliable tests for it. However Lyme disease (not Lymes disease) became an alternative medicine explanation for everything vague and many people became obsessed with thinking they had it based on vague symptoms like fatigue. When they couldn’t get positive test results to confirm their belief, the Lyme disease online communities established the idea that the tests cannot detect their version of the disease. It’s a belief that allows anyone to diagnose with Lyme disease in a completely unprovable way.

and the symptoms vary wildly from person to person.

This belief is an unfortunate result of the online Lyme communities encouraging everyone with any unexplained symptoms to believe it’s caused by Lyme disease that can’t be detected. When the disease becomes redefined as being untestable and causing wildly different symptoms in everyone, it becomes impossible to say that anyone doesn’t have it. If you have any vague symptoms like feeling tired, a Lyme disease community will encourage you do believe that it’s caused by an undetectable case of Lyme disease.

There is a lot of strong evidence that these patients do not have Lyme disease, but they’re always good at coming up with another reason why they have it but it can’t be detected in them specifically

lstroud• 2 months ago

MCAS is pretty well defined and is associated with it.

motbus32• 2 months ago

I know someone's case who got it 3 times. The first 2 times full recover in no time. The third one took couple of months and now feels tired all the time, lost all sense of taste and smell, swollen tongue, body pain of sitting still due to the compression of muscles.

This person told me it was sure it was related to COVID because there was nothing before or after it and that was the only thing that happened.

Kinda sucks to thing that everytime it might be a chance for that or worse

kranke15510• 2 months ago

Maybe tell this person to see an autonomic dysfunction expert.

motbus32• 1 month ago

Not sure if needed. It depends much on your exposure. If you have someone on your family it is a factor of risk. Which just makes things insane considering that they exploit it get couple hundred bucks more per insurance.

It has been cheaper to not work for the healthcare system lately. Also because people are a**oles to nurses and the rest of the staff.

wetmore• 2 months ago

I had covid 7 or 8 times lol. Basically 2-3 times a year from Jan 2022 until spring of 2025. Luckily there have been seemingly no long-term effects for me, and it's been over a year since I last tested positive.

OutOfHere• 2 months ago

This author and the article is utterly and chronically useless and cringe. It offers no insight. If you want something that's more useful:

Long COVID may be fueled by inflammation and tiny clots (2026)

https://www.sciencedaily.com/releases/2026/01/260107225532.h...

whiskey_ranger• 2 months ago

Covid almost killed me. I distinctly remember feeling near death when the hospital attempted a last-ditch effort with a transfusion. I don’t remember all of the details, but I know that someone, somewhere, saved my life. And I’ve done fuck all with that gift — it’s been almost five years.

Personally, the only long Covid symptom I know of is that I have a coughing fit after every meal (and sometimes during). Some foods seem to lead to worse fits, but anything other than liquid will make me cough to some degree. Sometimes, it’s to the point that I see stars and nearly pass out.

All in all, I got off easy with Covid. It could have been worse.

saulpw• 2 months ago

coughing fit after every meal (and sometimes during).

This might be stomach acid aspirating into your lungs, from GERD or similar caused/exacerbated by Covid, and that may have negative consequences for your health apart from the coughing.

The Causes of Long Covid

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