Canadian blood services specifically doesn't allow me to donate blood. Admittedly, I fear needles pretty fiercely anyway so it's not something I'm going to be fighting.
I find it interesting though that the argument to donate blood is that one's blood might be toxic. That giving away your toxic blood might make your own blood less toxic.
Yeah, the article mentions recipients of the toxic blood. I wonder if there will be more research to identify any risks for recipients
> The logic in removing them is simple: PFAS work by binding to serum proteins in the blood; removing some of this blood, therefore, would lead to the reduction of forever chemicals in the bloodstream. As to the question of what happens to recipients of this blood: “Perfluoroalkyl and polyfluoroalkyl substances are ubiquitous, and no threshold has been identified that poses an increased risk to recipients of donated blood components.”
That prompts a curious thought: If you dump 1 unit of your toxic blood into the 9 units of blood inside the body of a transfusion recipient, then how toxic does their blood become? 1/10 toxic?
I've also wondered, is it possible for a transfusion recipient to fail a drug screening test because their doner had recently consumed drug prior to their donation.
Therapeutic phlebotomy, basically bloodletting, is a common treatment for hemochromatosis, iron overload. It would make sense as a treatment if you've got too much of a substance in your system, that substance accumulates in your blood, and you're otherwise healthy enough to tolerate the loss of blood periodically. Depending on the substance, there may be other means that are more effective, or less invasive, of course; and if it's an urgent need to reduce the substance, bloodletting would likely be too slow.
I also had an "irrational" fear of donating blood and needles, and being encouraged by my girlfriend, also started doing it. Well, I did it once a couple of months ago and almost passed after some minutes (they had to stop). Apparently, this is not uncommon for young skinny males. But maybe my excitement also didn't help. Will try again :D
Brings up an interesting question. Say you couldn't donate due to tattoos, needle use from steroids or IV drugs ("have you ever injected anything not prescribed by a doctor"), gay or paid sex, etc
It’s not bloodletting but some things do come out in sweat, I remember reading a paper that demonstrated heavy metals come out in sweat in significant amounts. Perhaps other things do as well.
During blood donations there's a step where they ask you if it's okay to use your blood (which is indicated by selecting one of two barcode stickers that the technician can't interpret). I assume this is for people who are pressured to donate blood as a group but don't want to out themselves as being ineligible. You could just go do that and select the "don't use my blood" sticker.
Correct, you take one sticker and place it on the form you're filling out, and place the other somewhere else, I forget where. So when the tech turns around they can't know which one you picked.
Some folks on certain medications (or just because) can have an increase in red blood cell production, sometimes called "blood thickening," I believe, and they can sometimes just get a prescription from a doctor to go to a donation facility. Or some facilities will still just allow you to do this if you tell them you need to get rid of excess blood for the reasons above, and then they dispose of it. (Not everyone requires a doctor's prescription for it.)
That's just one use case, obviously, so there is a system for some to get rid of excess blood, at least, in a similar manner as you would donate.
There was some discussion[0] on HN a few weeks ago organizations (like the Red Cross[1]) not accepting donations from patients who require therapeutic phlebotomy (hemochromatosis patients, for example) because their donation provides the donor a benefit (and therefore isn't strictly altruistic). That sent me down an interesting rabbit hole of reading (link in discussion).
I didn't realize that. I was briefly thought to have hemochromatosis, and had been "self-treating" via the Red Cross for years.
It turns out I didn't have hemochromatosis. It was merely a bit high, but knowing that I donated so often (both whole blood and platelets, which you can do more often), there was concern that the "self-treatment" was covering up a real problem.
I had not heard at the time that they wouldn't have wanted my blood. It was over a decade ago, and it's possible that the policy didn't exist then.
I have hemochromatosis and here in Germany it's impossible for me to donate blood. It's not actually forbidden, afaik, but no company want's to give 'contaminated' blood to patients, even though it would be perfectly fine.
I know life often imitates The Onion, but "passersby were amazed at the unusually large amounts of blood" was not one of the headlines i ever expected to cross the chasm.
> Some people, he tells us, absorb too much iron, often as a result of a genetic condition called hereditary hemochromatosis. Over the years, the extra iron builds up slowly in people's bodies, causing damage to organs such as the liver and heart as well as the joints.
> What contains a lot of iron? Red blood cells! That's what. Thus, the therapy for iron overload (as it's also called) is to draw pint after pint of blood from patients until the iron stores drop to an acceptable level, and thereafter draw the occasional unit of blood so those levels don't creep up again.
Sounds very familiar if you replace "iron" with "PFAS".
Hemochromatosis is one, I was suspected to have it when I was younger and regular blood donations was an effective way to reduce my blood iron. Turns out I don't actually have the condition (it's genetic and doesn't go away as you age, whereas my extremely high iron resolved on its own), but I'm not mad about it, just a change I've welcomed.
I wasn't able to find a reference, but I believe it's possible to go to a blood drive and have blood drawn and discarded. This provides cover for people who are ineligible but don't want their friends/coworkers to know.
Alternatively, it's easy to DIY if you are so inclined. You just need some sterile needles and alcohol swabs.
Science is, and has always been, about adjusting our flawed, incomplete models as new evidence emerge. We shouldn't let our ill-informed preconceptions prevent humanity from moving forward.
If removing blood from the body takes forever chemicals with it and we have no practical way of filtering those chemicals out, then discarding the blood (yes, bloodletting) is the moral way to do it. Irrational and uneducated biases need not apply.
Donate your perfluoroalkyl and polyfluoroalkyl substances (PFAS) to those in need!
Hmm:
> As to the question of what happens to recipients of this blood: “Perfluoroalkyl and polyfluoroalkyl substances are ubiquitous, and no threshold has been identified that poses an increased risk to recipients of donated blood components.”
By putting "toxic chemicals" in the title along with that sentence in the body, it sure seems like they're trying to have their cake and eat it too with this article. It also lists a bunch of negative things that are associated with PFAS levels. They're toxic, and associated with a bunch of bad things, but don't worry.
> apart from being identified as potentially carcinogenic, PFAS are associated with “low fetal weight, impaired immune response, thyroid function abnormalities, obesity, increased lipid levels, liver function alterations, and, potentially, an increased risk of some malignant neoplasms.”
I suppose that most blood recipients are probably better off with increased PFAS than going without the infusion, but the article sure presents the situation clumsily.
My guess is that the person who needs blood cares more about getting the blood or plasma than the small amount of PFAS in it, which they likely have already.
If this causes more people to donate, it's probably a good thing overall, even if the people doing it are doing so in the hopes of cleansing their own system of these chemicals.
With respect to HIV, there is an alternative to get non-contaminated blood.
With respect to PFAS, which is a general societal/environmental issue it's likely that all donated blood has roughly the same PFAS levels, so recipient either gets blood with PFAS or no blood at all; and the "new" blood might have slightly more or less PFAS than the recipients current blood, but the recipient already has a comparable level of PFAS anyway.
I would argue additionally that once the person in need of blood has recovered they can simply donate blood and in so doing enjoy the benefits of reduced PFAS levels and hopefully save someone else's life with that blood!
if there is no other choice. Yes, reluctantly, I would accept hiv. (i.e. I accept days to years duration of life vs minutes to hours)
The thing is, donated blood is always in short supply. you dont have much choice, when you have a serious blood-loss.
edit: I would be very angry if sombody would have chosen to use hiv blood on me while I was uncounciuos. Similar to how I would be angry if my arm would be amputated, while my conciousness was away.
Presumably it's even odds as to who has more PFAS: the donor or the recipient. And if you need a blood transfusion (often in an emergency), the PFAS is probably a small negative on a hugely positive treatment. It's like pesticides on plants: it's probably slightly unhealthy to eat the small level of pesticides on most plant food, but it's worse to miss out on all the nutrition in plants.
They're basically saying: "Sure, you're passing the buck, but there's no evidence that your reduction in PFAS results in an increase of PFAS to the recipient. Because we haven't looked." and then calling that "Science".
If that were the case, they surely would have cited the studies.
But let do some simple math. Let's say I (and a dozen other donors) have 10ng/mL of PFAS in my system and a recipient has 5ng/mL. Assuming 20 pints of blood in a human for the rest of this word problem. Recipient requires a transfusion of 10 pints which happen to be sourced by those 12 donors, What is their PFAS load after the transfusion?
On the first donation you're expected to have an average level, and thus not to increase the pfas level of the recipient. On all subsequent donations you're expected to be below average and thus reduce the level of the recipient. So I think them being careful is clearly not hypocrisy here.
If donator's blood has same concentration of pfas as recipients, the recipient's concentration does not change! Also, the recipient has probably just lost blood, so total amount of pfas won't change either, and taking into account that people that donate blood do so often with some regularity, the donators blood actually is likely to have less pfas than the recipients original blood.
It should be possible for some recipients to donate plasma after they recover. So if pfas levels are a real concern, there’s an easy solution for at least some of the recipients.
Even if the body doesn't have the equipment built in to deal with it it's not a stretch to believe that we could build an external machine specialized to the task - whether dialysis machines can do it on their own or not I'm uncertain.
What if the blood collectors just find a way to filter out PFAs so they don’t get into your donation and they collect a pure sample, and overtime you just keep saturating your blood with PFAs through constant donations? No thanks.
If this was conclusively proven to be a benefit, you could acquire the equipment, drain a pint of your own blood, and then put it in the compost every couple months.
Yes, just as that is the standard treatment for hemochromatosis. Just because it is the wrong treatment for most things does not mean it has zero therapeutic value in specific circumstances.
Sheesh, I can't believe the percent of negative comments! Someone finally figured a way to reduce PFAS. It's a hugely positive finding, especially in light of people being able to keep their red blood cells. Hopefully it can be ruled as a safe long-term solution for now. Looking forward to reading updates on this research.
And btw, donating plasma doesn't mean other people will get your PFAS; many things can be done with plasma besides injecting into other people.
Even if someone else would get your PFAS its most likely they have them as well and its certainly better than dying of blood loss or not treating other serious issues that rely on various blood products.
Absolutely, the point of a blood transfusion is that a body needs blood replenished faster than it can produce it. A blood transfusion now, PFAS or no, gives someone a chance to survive (and who knows, maybe donate blood themselves at some point)
There are diseases where you get regular transfusions. For these patients, PFAS would become a problem since they are, by definition, not subject to degradation. Unless, of course, the patients are physically losing blood.
Which makes me wonder if women have a specific advantage on this matter. I do remember reading that regular blood donations show health benefits, and that women get them "for free", so to speak. This may be part of the reason.
I haven't heard of PFAS before but the findings kind of sounds straightforward? If something that can be synthesised by the body gets contaminated by external pollutants, it should get purer by removing part of the contaminated material since it's going to be replaced by newly synthesised supplies and result in dilution of the pollutant.
In other words, dilution is solution of pollution[0]
PFAS is teflon. If you ever cooked w/ teflon pans you probably ingested some PFAS directly from that. It's called 'forever chemicals' because it doesn't degrade, it's literally there forever (or nearly), very hard to get rid of.
There's a really good documentary called Dark Waters about a lawyer for the Chemical industry who switches sides after his home town has a lot of people get sick from Dupont poisoining people and he's been fighting a crusade against them ever since. It stars Anne Hathaway and Mark Ruffalo.
> Regular plasma donation is probably much worse for your long term health than ppb levels of pfas.
You should in the very least read the summary. Even though the trial referred in the submission tracked regular plasma donations, the reduction of "forever chemicals" was not a function of how regular they were, only the volume of blood/plasma donated by the firefighters.
Also, I'd be surprised if the rate wasn't tied to the initial concentration, which would mean that increased rates lead to diminished returns.
If you're getting a blood donation, you've likely lost a lot of blood that is being made up by the donation. So you lost blood and by extension forever chemicals and are replacing blood and by extension forever chemicals. I bet it's a wash as far as +- chemicals.
Also, choking people get bruises to the abdomen when someone performs the Heimlich maneuver on them, and people with cancer get pumped full of chemicals which just about kill them. That treatments also cause harm is pretty normal in medicine.
Detoxification/cleansing has always been real, in the alternative and conventional/allopathic medical worlds. I don't know any school of thought that denies the benefits of cleansing (within reason); only those who disagree on how to go about it.
Most Detoxing your hear about (and all from “alternative” (read: fake) medicine) is a marketing strategy for treating nonexistent conditions.
Body acidity is a myth, cleaning organs like the kidney or liver is a myth, and all the detox treatments peddled have never been shown to actually remove any toxins from a human.
Detoxification is not any part of “conventional medicine”, or, to give it appropriate weight “medicine”. It’s also not part of any “school of thought” that isn’t crackpot garbage (so called “alternative medicine”)
You clearly don't know what you're talking about. Detoxing occurs in medical settings every single day, in every hospital, in almost every clinic.
Example: people overdose on Tylenol, and we may have to give them NAC (N-acetyl-cysteine) to boost their depleted glutathione levels and get rid of the toxins.
Another example: people ingest a poison, and sometimes it's appropriate to make them drink activated charcoal so it can bind the toxins. These types of "Detoxes" are also common (but over-used) in the alternative world.
Another example: with some infections, you can't give too many antibiotics at once or it will overload the body's detox capacity, so things are done to help.
Another example: 9/11 workers who were exposed to massive amounts of toxins from burning building materials afterwards suffered from that exposure. Conventional medical doctors came up with detox protocols including the use of Far Infrared Saunas to help decrease the toxin load in their bodies.
Seems like vampires would end up concentrating these toxic chemicals over time.
Maybe a story prompt about vampires that discover they are dying due to heavy metal buildup in their systems. They go out in search of remote island nations that have populations with little exposure to modern low level contaminants. Have to adopt to slow island life.
>> Unfortunately, a PFAS blood test is not a routine lab test that can be processed by your local lab and covered by your health insurance. In fact, there are only a handful of labs certified to test for PFAS in blood and the out of pocket cost for this test is out of reach for most people.
Probably not, honestly. For most tests, the risks associated with a false positive outweigh the benefits of marginally earlier detection.
Humans aren't precise machines, each person has different values and different value ranges for standard measurements - and asymptomatic deviations frequently mean nothing whatsoever. On the other hand investigations can be invasive, painful, risky and expensive.
There's a reason most tests aren't recommended for folks outside certain risk categories (age, family history, etc). And in a litigious society like America, it's not because it's expensive. There's some specific diseases where there's a lot of data backing this thesis - certain cancers for instance.
> For most tests, the risks associated with a false positive outweigh the benefits of marginally earlier detection.
If these tests aren't run, then I am not sure if it would be "marginally earlier", it might be much later or even never that the problem is discovered.
If they are run, the results could be uninformative (https://en.wikipedia.org/wiki/Base_rate_fallacy). Too many false positives could lead to risky treatment and be dangerous. Testing each positive again would still create false positives. I don't know the numbers in this case, but I wouldn't be surprised if accurate mass testing were impractically expensive.
This should only be a problem if you don't adjust the models. If you run a huge number of tests, you can create far more detailed models and thus reduce the false positive rate.
Ideally, all chemical processes in the body could be known and we could have an almost "mechanical" model of the body. How else but with more testing can be reach that knowledge?
> This should only be a problem if you don't adjust the models. If you run a huge number of tests, you can create far more detailed models and thus reduce the false positive rate.
Can you? The problem is the test's sensitivity and specificity, there's not much statistical work to do after the test on a single case. It's not an advanced model deciding whether you're sick or not.
> Ideally, all chemical processes in the body could be known and we could have an almost "mechanical" model of the body. How else but with more testing can be reach that knowledge?
Yeah, ideally we would. Not a doctor, but as far as I can tell, we're a thousand years away from that.
I don't know why this comment is downvoted. Let me elaborate a little on what I think they meant.
All the risks associated with false positives (other than the side effects of actually drawing blood once a year, which I think is negligible) can be removed by simply not overreacting. Find a cancer? Well, consider not subjecting yourself to chemo just to get rid of it. Some cancers will kill you by winter, some will just stay there until you die of something else. How will we know which is which? By testing lots of people over long periods of time to see what's harmless and what's actually really bad. Or as the previous commenter said: "That's the whole point of establishing a baseline."
The parents premise is wrong. You can't just "establish a better baseline" and "if the test says you might have cancer don't worry about it maybe?" The former is hampered by base rate fallacy [1] (specifically the part about disease in a low-incidence population) and the in the latter, if you're going to disregard the outcome why are you testing?
A concrete example is the NHS recommends against the PSA prostate cancer antigen screening test completely for everyone of any age because this test does more harm than good. They have a good write-up on why. [2]
Generally I agree this data should be collected, but aggregated and not used for individual treatments.
I think the value in regular blood tests is to get an idea of what normal values are for you specifically. For some diseases/conditions the blood levels have such a big range that it is more useful to know the delta.
We hardly ever measure the “good” or stable cases so when we start testing stuff when we are ill there is very little data on what is normal or even normal for you.
Ive heard of cars where due to family history someone preemptively screened on certain blood values. When those changed they knew something was up, even though the value was still within normal range it was up 100x for them.
This is true, although I would prefer to still test everyone for plausibly important things to feed data analysts who might eventually discover something useful.
I'd love for that to be true, but there's a good chance that in doing broad tests you are incurring costs (both to patient health and cost [whether paid by patient, gov, or insurance company]) without getting anything beyond noisy data without useful signal
The people vested in using lead in fuel said so out of profit motive, but it seems lead was widely known to be harmful for hundreads of years [0] before it was using it fuel.
There’s a theory (see slimemoldtimemold.com) that PFAS cause obesity (or, rather, cause increased hunger which in turn causes obesity). This seems like a great way to actually test that hypothesis.
212 comments
[ 1.0 ms ] story [ 291 ms ] threadI find it interesting though that the argument to donate blood is that one's blood might be toxic. That giving away your toxic blood might make your own blood less toxic.
> The logic in removing them is simple: PFAS work by binding to serum proteins in the blood; removing some of this blood, therefore, would lead to the reduction of forever chemicals in the bloodstream. As to the question of what happens to recipients of this blood: “Perfluoroalkyl and polyfluoroalkyl substances are ubiquitous, and no threshold has been identified that poses an increased risk to recipients of donated blood components.”
I've also wondered, is it possible for a transfusion recipient to fail a drug screening test because their doner had recently consumed drug prior to their donation.
I’d certainly be happy to have blood drawn if it meant lowering blood toxicity I had no other way of treating.
Are there services for bloodletting?
So even the tech can’t see that it’ll ultimately be disposed of?
That's just one use case, obviously, so there is a system for some to get rid of excess blood, at least, in a similar manner as you would donate.
[0] https://news.ycombinator.com/item?id=30808856
[1] https://www.redcrossblood.org/donate-blood/blood-donation-pr...
It turns out I didn't have hemochromatosis. It was merely a bit high, but knowing that I donated so often (both whole blood and platelets, which you can do more often), there was concern that the "self-treatment" was covering up a real problem.
I had not heard at the time that they wouldn't have wanted my blood. It was over a decade ago, and it's possible that the policy didn't exist then.
It amused me very much at the time to think that "bloodletting" might, in fact, be medically prescribed.
> Some people, he tells us, absorb too much iron, often as a result of a genetic condition called hereditary hemochromatosis. Over the years, the extra iron builds up slowly in people's bodies, causing damage to organs such as the liver and heart as well as the joints.
> What contains a lot of iron? Red blood cells! That's what. Thus, the therapy for iron overload (as it's also called) is to draw pint after pint of blood from patients until the iron stores drop to an acceptable level, and thereafter draw the occasional unit of blood so those levels don't creep up again.
Sounds very familiar if you replace "iron" with "PFAS".
Alternatively, it's easy to DIY if you are so inclined. You just need some sterile needles and alcohol swabs.
Science is, and has always been, about adjusting our flawed, incomplete models as new evidence emerge. We shouldn't let our ill-informed preconceptions prevent humanity from moving forward.
If removing blood from the body takes forever chemicals with it and we have no practical way of filtering those chemicals out, then discarding the blood (yes, bloodletting) is the moral way to do it. Irrational and uneducated biases need not apply.
Hmm:
> As to the question of what happens to recipients of this blood: “Perfluoroalkyl and polyfluoroalkyl substances are ubiquitous, and no threshold has been identified that poses an increased risk to recipients of donated blood components.”
> apart from being identified as potentially carcinogenic, PFAS are associated with “low fetal weight, impaired immune response, thyroid function abnormalities, obesity, increased lipid levels, liver function alterations, and, potentially, an increased risk of some malignant neoplasms.”
I suppose that most blood recipients are probably better off with increased PFAS than going without the infusion, but the article sure presents the situation clumsily.
If this causes more people to donate, it's probably a good thing overall, even if the people doing it are doing so in the hopes of cleansing their own system of these chemicals.
We could also say that given a choice between death and HIV, the blood recipient would still want the blood.
…yes?
With respect to PFAS, which is a general societal/environmental issue it's likely that all donated blood has roughly the same PFAS levels, so recipient either gets blood with PFAS or no blood at all; and the "new" blood might have slightly more or less PFAS than the recipients current blood, but the recipient already has a comparable level of PFAS anyway.
The thing is, donated blood is always in short supply. you dont have much choice, when you have a serious blood-loss.
edit: I would be very angry if sombody would have chosen to use hiv blood on me while I was uncounciuos. Similar to how I would be angry if my arm would be amputated, while my conciousness was away.
https://www.overcomingbias.com/2008/08/doctor-there-ar.html
But let do some simple math. Let's say I (and a dozen other donors) have 10ng/mL of PFAS in my system and a recipient has 5ng/mL. Assuming 20 pints of blood in a human for the rest of this word problem. Recipient requires a transfusion of 10 pints which happen to be sourced by those 12 donors, What is their PFAS load after the transfusion?
˥ɯ/ƃuϛ˙ㄥ :ɹǝʍsu∀
Veritasium has a great YouTube video about this: "The Man Who Accidentally Killed The Most People In History"[0]
[0] - https://www.youtube.com/watch?v=IV3dnLzthDA
A filter which excludes all of the things you don’t want in your blood and left anything besides plain water would be hard, not worth the trouble.
Volume.
A blood sample is at a stretch max 20ml. A blood donation is about 300ml.
And btw, donating plasma doesn't mean other people will get your PFAS; many things can be done with plasma besides injecting into other people.
Which makes me wonder if women have a specific advantage on this matter. I do remember reading that regular blood donations show health benefits, and that women get them "for free", so to speak. This may be part of the reason.
It's not hard to imagine the human body optimizing for those conditions, which would make permanently holding onto all your blood suboptimal.
In other words, dilution is solution of pollution[0]
[0] https://www.youtube.com/watch?v=OvnllquGmgg
There's a really good documentary called Dark Waters about a lawyer for the Chemical industry who switches sides after his home town has a lot of people get sick from Dupont poisoining people and he's been fighting a crusade against them ever since. It stars Anne Hathaway and Mark Ruffalo.
You should in the very least read the summary. Even though the trial referred in the submission tracked regular plasma donations, the reduction of "forever chemicals" was not a function of how regular they were, only the volume of blood/plasma donated by the firefighters.
Also, I'd be surprised if the rate wasn't tied to the initial concentration, which would mean that increased rates lead to diminished returns.
I think fad diets are the terrority where it gets a bit unreasonable (juice cleanses?). Chakra/Qi cleanses?
Body acidity is a myth, cleaning organs like the kidney or liver is a myth, and all the detox treatments peddled have never been shown to actually remove any toxins from a human.
Example: people overdose on Tylenol, and we may have to give them NAC (N-acetyl-cysteine) to boost their depleted glutathione levels and get rid of the toxins.
Another example: people ingest a poison, and sometimes it's appropriate to make them drink activated charcoal so it can bind the toxins. These types of "Detoxes" are also common (but over-used) in the alternative world.
Another example: with some infections, you can't give too many antibiotics at once or it will overload the body's detox capacity, so things are done to help.
Another example: 9/11 workers who were exposed to massive amounts of toxins from burning building materials afterwards suffered from that exposure. Conventional medical doctors came up with detox protocols including the use of Far Infrared Saunas to help decrease the toxin load in their bodies.
Maybe a story prompt about vampires that discover they are dying due to heavy metal buildup in their systems. They go out in search of remote island nations that have populations with little exposure to modern low level contaminants. Have to adopt to slow island life.
Those medieval sawbones knew some stuff.
But PFAS testing is not the norm?
Per a Tedx talk on this subject: https://www.nrdc.org/experts/anna-reade/pfas-blood-tests-nee...
>> Unfortunately, a PFAS blood test is not a routine lab test that can be processed by your local lab and covered by your health insurance. In fact, there are only a handful of labs certified to test for PFAS in blood and the out of pocket cost for this test is out of reach for most people.
Humans aren't precise machines, each person has different values and different value ranges for standard measurements - and asymptomatic deviations frequently mean nothing whatsoever. On the other hand investigations can be invasive, painful, risky and expensive.
There's a reason most tests aren't recommended for folks outside certain risk categories (age, family history, etc). And in a litigious society like America, it's not because it's expensive. There's some specific diseases where there's a lot of data backing this thesis - certain cancers for instance.
If these tests aren't run, then I am not sure if it would be "marginally earlier", it might be much later or even never that the problem is discovered.
Ideally, all chemical processes in the body could be known and we could have an almost "mechanical" model of the body. How else but with more testing can be reach that knowledge?
Can you? The problem is the test's sensitivity and specificity, there's not much statistical work to do after the test on a single case. It's not an advanced model deciding whether you're sick or not.
> Ideally, all chemical processes in the body could be known and we could have an almost "mechanical" model of the body. How else but with more testing can be reach that knowledge?
Yeah, ideally we would. Not a doctor, but as far as I can tell, we're a thousand years away from that.
All the risks associated with false positives (other than the side effects of actually drawing blood once a year, which I think is negligible) can be removed by simply not overreacting. Find a cancer? Well, consider not subjecting yourself to chemo just to get rid of it. Some cancers will kill you by winter, some will just stay there until you die of something else. How will we know which is which? By testing lots of people over long periods of time to see what's harmless and what's actually really bad. Or as the previous commenter said: "That's the whole point of establishing a baseline."
A concrete example is the NHS recommends against the PSA prostate cancer antigen screening test completely for everyone of any age because this test does more harm than good. They have a good write-up on why. [2]
Generally I agree this data should be collected, but aggregated and not used for individual treatments.
[1] https://en.wikipedia.org/wiki/Base_rate_fallacy
[2] https://www.nhs.uk/conditions/prostate-cancer/psa-testing/
We hardly ever measure the “good” or stable cases so when we start testing stuff when we are ill there is very little data on what is normal or even normal for you.
Ive heard of cars where due to family history someone preemptively screened on certain blood values. When those changed they knew something was up, even though the value was still within normal range it was up 100x for them.
[1] https://www.youtube.com/watch?v=rW3DGnHO2iY
"The Problem With Silicon Valley Medicine": https://www.youtube.com/watch?v=rW3DGnHO2iY
There are studies like the UK biobank that are trying to collect longitudinal information about a huge number of people, but they're volunteers.
[0] https://www.youtube.com/watch?v=IV3dnLzthDA
https://empowerdxlab.com/products/product/pfas-exposure-test
[0]: https://testdirectory.questdiagnostics.com/test/test-detail/...
https://www.davidbrin.com/fiction/givingplague.html