This is certainly an improvement over a lab test, but a continuous monitoring solution would dramatically expand the utility.
You could rate employers on the median cortisol levels of their employees during and after the work day.
At an individual level, those of us that are not very self-aware of our stress levels could monitor it objectively and determine stressors and implement and monitor interventions to reduce stress.
This is one of those ideas that might sound good when you don't think about secondary effects, but is actually commonly accepted to be a bad idea in the medical community. Similar to white coat hypertension [0], measuring your stress can induce stress, whether that's worrying about whether you're in a good range, getting more stressed when you find out you're already stressed, or etc. This is why continuous monitoring is usually applied as little as reasonably possible, unless absolutely necessary like diabetes, ER, etc.
There's no reason to think that continuous monitoring with a comfortable wearable would contribute to a white coat syndrome. The Wikipedia link that you cited actually says that at-home blood pressure readings are more reliable than those taken by a professional in a clinic because (it is believed) that the presence of another human administering a single test is what causes stress concerning the test. With the multiple, self-administered approach, there is no single test to fixate on, and no other human administering it.
> This is why continuous monitoring is usually applied as little as reasonably possible
The reason it is applied as little as possible is because it has been prohibitively expensive. For most things there is a benefit to sampling more often, and what sampling rate is adequate is entirely dependent on the maximum frequency that you need to observe. Another way of phrasing that is if it can change quickly, then you need to sample more often.
I wonder why these kinds of arguments gain such wide acceptance.
specifically - measuring x has negative consequences, so don't measure x.
then at some point it becomes, don't bother measuring x ever.
Normally I hear abotu this like tests that can find cancer early, or full body MRIs.
I think these measures might actually be really good to establish a baseline and changes over time, or catch things early.
If the problem is that knowing leads to stress, maybe there could be a solution in the portrayal of the data. Maybe it could be "doctor, don't tell me unless there is a trend"
Doctors frequently give a disclaimer before ordering PSA tests, for example.
Smartwatches have been measuring all sorts from our bodies for a long time and whilst some people develop this type of thing, the majority have not. These watches have been monitoring stress in the form of HRV for many years now.
I felt like I was trapped in a cycle of bad sleep -> stress -> worse sleep. And the two things that helped the most were exercising to burn of extra, nervous energy, and my fitbit breaking so I couldn't look at it and worry about how bad my sleep was.
This is exactly the opposite of what which is written in the quoted wikipedia article:
> Ambulatory blood pressure monitoring and patient self-measurement using a home blood pressure monitoring device is being increasingly used to differentiate those with white coat hypertension or experiencing the white coat effect from those with chronic hypertension
Continuous monitoring is a viable workaround wrt. white coat symptoms. It is just a lot more effort and expensive.
There are devices called "holter monitors" that a person wears continuously and which measure your blood pressure frequently. I would call this continuous though it's more like every 15 minutes or whatever it's programmed for. It's all without your intervention. My ex bought one when they wanted more data about their high blood pressure.
I'm well aware of this, but this is different from what we're discussing here. While Holters measure continuously, they don't give you continuous feedback. The general procedure is that the data is either gathered and downloaded or sent over network and the patient sees it only after the gathering is done.
Because I fainted, I wore a holter monitor for a month that did not measure blood pressure but instead my EEG, uploading the data via the cellular network. My cardiologist said it measured about 1 million heatbeats in that time.
This is what the kids call gatekeeping, not a whole lot different from the old “if the proles are allowed to read the religious texts they will get it wrong, better limit such things to priests.”
Yes, during the transition phase where information becomes available, some people will handle it badly, misinterpret, and generally be worse off.
But that’s a terrible reason to withhold knowledge, especially about peoples’ own bodies.
I suppose to mitigate that you could have that data not immediately viewable to the patient because seeing "stress line go up" would be pretty stressful and would skew the data anyway.
This would end up having effects like causing employers to discourage their employees from drinking coffee or exercising, both of which acutely raise cortisol levels.
Oh sure! While we’re at it, let’s increase the existing dystopia by giving employers the ability to track our stress levels and let them “compensate” as they see fit…
People being able to measure it on their own != employers being given the right to require doing so and handing over the data. Matter of fact, you could outright ban employers from doing so. But then the topic of moan would become that regulations bad, and this would be then quickly portrayed as an industry backsetting obstacle.
I wonder if a similar technique could be used for Melatonin in saliva so that noninvasive circadian phase testing could be performed outside of the lab.
I'm convinced that if we actually looked at the circadian phase of the general population more closely we'd find A LOT of people with wonky clocks [1][2].
I've come to realize in recent months that I'm rocking a ~3h phase advance. Not terrible but it can sometimes make getting enough total sleep time challenging (bright light therapy in evenings really helps).
As a Type 1 Diabetic, I'd love to have a continuous version of this to pair with my Continuous Glucose Monitor, mainly because I'm convinced that glycogen output from the liver is what's causing a lot of variability, and would explain, e.g. early morning fasting increases in blood sugar.
What you're describing is likely the dawn phenomenon - cortisol's morning spike triggers hepatic glucose production, and continuous monitoring could finally give diabetics actionable data to adjust treatment timing accordingly.
This is certainly an improvement over a lab test, but a continuous monitoring solution would dramatically expand the utility.
You could rate employers on the median cortisol levels of their employees during and after the work day.
At an individual level, those of us that are not very self-aware of our stress levels could monitor it objectively and determine stressors and implement and monitor interventions to reduce stress.
This is one of those ideas that might sound good when you don't think about secondary effects, but is actually commonly accepted to be a bad idea in the medical community. Similar to white coat hypertension [0], measuring your stress can induce stress, whether that's worrying about whether you're in a good range, getting more stressed when you find out you're already stressed, or etc. This is why continuous monitoring is usually applied as little as reasonably possible, unless absolutely necessary like diabetes, ER, etc.
[0] https://en.wikipedia.org/wiki/White_coat_hypertension
There's no reason to think that continuous monitoring with a comfortable wearable would contribute to a white coat syndrome. The Wikipedia link that you cited actually says that at-home blood pressure readings are more reliable than those taken by a professional in a clinic because (it is believed) that the presence of another human administering a single test is what causes stress concerning the test. With the multiple, self-administered approach, there is no single test to fixate on, and no other human administering it.
> This is why continuous monitoring is usually applied as little as reasonably possible
The reason it is applied as little as possible is because it has been prohibitively expensive. For most things there is a benefit to sampling more often, and what sampling rate is adequate is entirely dependent on the maximum frequency that you need to observe. Another way of phrasing that is if it can change quickly, then you need to sample more often.
I wonder why these kinds of arguments gain such wide acceptance.
specifically - measuring x has negative consequences, so don't measure x.
then at some point it becomes, don't bother measuring x ever.
Normally I hear abotu this like tests that can find cancer early, or full body MRIs.
I think these measures might actually be really good to establish a baseline and changes over time, or catch things early.
If the problem is that knowing leads to stress, maybe there could be a solution in the portrayal of the data. Maybe it could be "doctor, don't tell me unless there is a trend"
Doctors frequently give a disclaimer before ordering PSA tests, for example.
>If the problem is that knowing leads to stress,
And who says information hazards don't exist. Gotta love how anxiety builds on anxiety.
Smartwatches have been measuring all sorts from our bodies for a long time and whilst some people develop this type of thing, the majority have not. These watches have been monitoring stress in the form of HRV for many years now.
A recent studied shows that Garmin watches like the one I have give HRV stress readings that don't correlate well to self-reports of stress
https://www.theguardian.com/technology/2025/aug/08/smartwatc...
The stress paradigm is probably the most holistic idea in medicine and I think any attempt to break it down to a number is reductivist.
I have a garmin watch and my take is that stress is not really a spot reading.
However, I am certain that some really bad days I've had have shown very high stress on the watch across the day.
also relaxing can show low stress during a window (like sleep is low stress)
I felt like I was trapped in a cycle of bad sleep -> stress -> worse sleep. And the two things that helped the most were exercising to burn of extra, nervous energy, and my fitbit breaking so I couldn't look at it and worry about how bad my sleep was.
> as little …
This is exactly the opposite of what which is written in the quoted wikipedia article:
> Ambulatory blood pressure monitoring and patient self-measurement using a home blood pressure monitoring device is being increasingly used to differentiate those with white coat hypertension or experiencing the white coat effect from those with chronic hypertension
Continuous monitoring is a viable workaround wrt. white coat symptoms. It is just a lot more effort and expensive.
Measuring your blood pressure at home is not continuous monitoring.
Continuously measuring blood pressure at home is continuous monitoring.
Unless you plan to sit at your desk all day and do nothing but press the button on your monitor, it isn't. These are two very different things.
There are devices called "holter monitors" that a person wears continuously and which measure your blood pressure frequently. I would call this continuous though it's more like every 15 minutes or whatever it's programmed for. It's all without your intervention. My ex bought one when they wanted more data about their high blood pressure.
I'm well aware of this, but this is different from what we're discussing here. While Holters measure continuously, they don't give you continuous feedback. The general procedure is that the data is either gathered and downloaded or sent over network and the patient sees it only after the gathering is done.
Because I fainted, I wore a holter monitor for a month that did not measure blood pressure but instead my EEG, uploading the data via the cellular network. My cardiologist said it measured about 1 million heatbeats in that time.
This is what the kids call gatekeeping, not a whole lot different from the old “if the proles are allowed to read the religious texts they will get it wrong, better limit such things to priests.”
Yes, during the transition phase where information becomes available, some people will handle it badly, misinterpret, and generally be worse off.
But that’s a terrible reason to withhold knowledge, especially about peoples’ own bodies.
I suppose to mitigate that you could have that data not immediately viewable to the patient because seeing "stress line go up" would be pretty stressful and would skew the data anyway.
It can be measured in a blind way.
This would end up having effects like causing employers to discourage their employees from drinking coffee or exercising, both of which acutely raise cortisol levels.
Oh sure! While we’re at it, let’s increase the existing dystopia by giving employers the ability to track our stress levels and let them “compensate” as they see fit…
People being able to measure it on their own != employers being given the right to require doing so and handing over the data. Matter of fact, you could outright ban employers from doing so. But then the topic of moan would become that regulations bad, and this would be then quickly portrayed as an industry backsetting obstacle.
Never a boring day.
Obligatory: https://en.wikipedia.org/wiki/Goodhart%27s_law
I wonder if a similar technique could be used for Melatonin in saliva so that noninvasive circadian phase testing could be performed outside of the lab.
I'm convinced that if we actually looked at the circadian phase of the general population more closely we'd find A LOT of people with wonky clocks [1][2].
I've come to realize in recent months that I'm rocking a ~3h phase advance. Not terrible but it can sometimes make getting enough total sleep time challenging (bright light therapy in evenings really helps).
1. https://www.sydney.edu.au/news-opinion/news/2025/07/16/depre...
2. Circadian Genes, Rhythms, and the Biology of Bipolar Disorder - https://www.youtube.com/watch?v=eSL5hC8bzcU
As a Type 1 Diabetic, I'd love to have a continuous version of this to pair with my Continuous Glucose Monitor, mainly because I'm convinced that glycogen output from the liver is what's causing a lot of variability, and would explain, e.g. early morning fasting increases in blood sugar.
What you're describing is likely the dawn phenomenon - cortisol's morning spike triggers hepatic glucose production, and continuous monitoring could finally give diabetics actionable data to adjust treatment timing accordingly.
I think it’s worth emphasizing that this is a “mix and read” test (like a COVID test), not something you could integrate in a smartwatch for example.
Still cool nonetheless.
I was in the study but my patch kept catching on fire when they put it on me.
I would apply the usual grain of salt approach to studies like these, but this one sounds insanely promising. Watching it closely
Oh I don't need this, I'm well aware of how stressed I am.