Also: ”A.J.K.P. and S.W.C. are co-founders and co-directors of Circadian Health Innovations PTY LTD.”
Lemme guess, looking for funding.
The whole publish-or-perish culture is a disaster that incentivizes cheating.
It should be considered just as valuable to have a few grad students working on replication as on original research, and that should not hurt the students' prospects.
This should be the work of grad students, not cranking out another paper or slaving for professors.
> We should also demand publication of failures -- it's ok to fail, but only if you publish about the failure.
I really want to have a journal that just publishes interesting duds. Someone else might look at your methodology and get their own idea.
> This should be the work of grad students, not cranking out another paper or slaving for professors.
But the professors need to arrange for this.
some charismatic, intelligent dude or dudette or couple with a curious but rather uneducated mind inviting grad students and scientists to discuss studies and pre-prints and so on, constantly babbling scientifically more or less correct nonsense but getting semantically corrected by the guests or something ... ... so viewers can feel "smartypants" and or relate and learn.
I'm sure there's podcasts but I don't listen to podcasts.
Maybe the next study could be “live king cobra in the bed results in sleep reduction”.
Probably a book and a TED talk to go with it.
You can almost see the grin as they wrote up the results.
The Beth Israel Deaconess Medical Center ran a trial on parachute use to prevent death and major trauma when jumping from aircraft, and gave half the people jumping a placebo (empty backpack) instead of a parachute. No joke.
But then, reading other responses, and taking into account the name of the journal, and the fact that it did get published, I realized it's a very good example of a flawed study, where everybody see a flaw because it's evident, whereas in other studies a flaw of the same magnitude might be quite difficult to see (I could give quite a few examples from my field).
The motive behind the study:
> Parachutes are routinely used to prevent death or major traumatic injury among individuals jumping from aircraft. However, evidence supporting the efficacy of parachutes is weak and guideline recommendations for their use are principally based on biological plausibility and expert opinion.
Results :
> Parachute use did not significantly reduce death or major injury (0% for parachute v 0% for control; P>0.9). This finding was consistent across multiple subgroups.
Methodology might have an influence on the result:
> Compared with individuals screened but not enrolled, participants included in the study were on aircraft at significantly lower altitude (mean of 0.6 m for participants v mean of 9146 m for non-participants; P<0.001) and lower velocity (mean of 0 km/h v mean of 800 km/h; P<0.001).
Conclusions
> Parachute use did not reduce death or major traumatic injury when jumping from aircraft in the first randomized evaluation of this intervention.
Implications
> Should our results be reproduced in future studies, the end of routine parachute use during jumps from aircraft could save the global economy billions of dollars spent annually to prevent injuries related to gravitational challenge.
Limitations
> However, the trial was only able to enroll participants on small stationary aircraft on the ground, suggesting cautious extrapolation to high altitude jumps.
I can already see the YouTube thumbnails: THIS IS THE STUDY PARACHUTE MAKERS DON'T WANT YOU TO SEE
> All authors suffered substantial abdominal discomfort from laughter.
Peer review just checks for obvious errors in study design, asks for more info if needed, and decides whether the paper is a good fit for the journal.
Watson and Crick's paper describing the structure of DNA wasn't peer reviewed. if you think they're wrong, try it for yourself and publish the results.
When a few groups all get the same result then you can be confident about the claims made. until then, it's just kind of interesting to think about, which is fine.
> A.J.K.P. and S.W.C. are co-founders and co-directors of Circadian Health Innovations PTY LTD
I do agree that this paper alone should not be used to help sell a product. But it looks like this paper just confirms previous findings using more rigorous methodology (see background):
"Light at night causes circadian disruption, (21–23) and is therefore a potential determinant of cardiovascular disease risk. Higher risks for coronary artery disease (24) and stroke (25) have been observed in people living in urban environments with brighter outdoor night light, as measured by satellite. Brighter night light has been cross-sectionally related to atherosclerosis, (26,27) obesity, hypertension, and diabetes (28) in small but well-characterized cohorts, using bedroom (26,27) and wrist-worn (28) light sensors. Moreover, experimental exposure to night light elevates heart rate and alters sympathovagal balance. (29) However, current evidence linking night light with cardiovascular risk is mostly within small cohorts, or relies on geospatial-level measurements of outdoor lighting, rather than measures of personal light exposure. (30,31)"
Sure but nobody claimed that.
> Watson and Crick's paper describing the structure of DNA wasn't peer reviewed.
I'd point out that outliers exist but that was before peer review become so popular.
Right now there's a good correlation between competency and peer review.
> if you think they're wrong, try it for yourself and publish the results.
Watson and Crick or the article?
For a balanced discussion of the article, it's reasonable to point out a lack of peer review to give context to what stage this is at. If "try it yourself" is the bar then I guess nobody comments? That doesn't seem like a good way to learn anything.
what outlier? I just picked a famous example, there are almost infinitely many examples to choose from...
>> if you think they're wrong, try it for yourself and publish the results. > Watson and Crick or the article?
yes
> For a balanced discussion of the article, it's reasonable to point out a lack of peer review to give context to what stage this is at.
The first thing that the pre-print says, in bold at the top of the page, is that this is a non-peer-reviewed article and shouldn't be used for clinical practice. so commenting "it's not peer reviewed" doesn't add anything
> If "try it yourself" is the bar then I guess nobody comments? That doesn't seem like a good way to learn anything.
"try it yourself" is the bar for determining the validity of the results. A comment section is not going to be able to determine the validity. My whole point is that it's worth discussing the article without waiting for a final peer-reviewed version of it. If you disagree with the results, you can point out a perceived flaw in the study or find papers which contradict the results so we can discuss something concrete
And there's even more almost infinitely many examples that say peer review is a strong signal.
> yes
If you were including the former, you were making a very rude argument by implying that anyone that values peer review is rendered invalid by that example.
> My whole point is that it's worth discussing the article without waiting for a final peer-reviewed version of it.
Telling people to shut up about peer review is bad for discussion.
My whole point is that it's ok to find research interesting and discuss it even though it's not peer reviewed yet.
> If you were including the former, you were making a very rude argument by implying that anyone that values peer review is rendered invalid by that example
No, I'm pointing out that not being peer reviewed is not automatically disqualifying and that the real way that or prove/disprove science is by replication attempts, not through peer review.
> And there's even more almost infinitely many examples that say peer review is a strong signal.
So you say, but if you think about it all papers in the ongoing replication crisis are peer reviewed. I know several peer reviewed papers which have inaccurate results, and in my experience having been on both sides of the peer review process I can tell you that it's pretty flawed since very few scientists are willing to invest a lot of their own time to do meticulous unpaid review of other people's work. Meanwhile, science progressed fine before peer review became standard in the 1970's.
> Telling people to shut up about peer review is bad for discussion.
I'll keep that in mind for the future but doesn't apply to anything I said. Maybe you should take a few minutes to read what I actually wrote instead of reacting emotionally
Publishing a pre-print is only valuable if your result hold long term. You're just stating that you did it first.
> Also: ”A.J.K.P. and S.W.C. are co-founders and co-directors of Circadian Health Innovations PTY LTD.”
The other edge of the "not impartial" sword: these are people who are highly familiar, likely experts, in the related field. Who else is more qualified to conduct such a study?Whoever does not have a monetary interest in the studied subject is the one who is more qualified. Same with smoking related research, same with children's toy paint related research. But the third edge is: These are phases of fraud that societies go through. They will happen, some will think they are legit, some won't, they disappear into some third world country after taking their sum. It always works like that. And that's predictive science right there.
I’m not really understanding the monetary interest angle. The monetary interest in this subject is the curtain and window-blind manufacturers.
The researches here have a company who sells body worn light sensors. And if their light sensor is good maybe other researchers interested in verifying this phenomena will purchase a few units from them. But they are far from the only company making light sensors. In fact if i want to verify this study i would buy sensors from anyone but them. For the sake of having independent proof free from biases.
> they disappear into some third world country after taking their sum
What sum, please tell me? Where do you see the riches here?
There is likely also a significant correlation between living in such conditions and exposure to pollution, especially inhaled particulate matter.
Such a correlation also holds elsewhere: living in a high-rise means no streetlights outside your window, and also yields cleaner air than living at or near street level; living in the countryside means practically no light pollution, but also much less traffic and thus much less particulates in the air.
Inhaled particulate matter is a leading cause of cardiovascular disease.
See e.g. https://www.sciencedirect.com/science/article/pii/S073510971...
In both humans and other animals, our internal sleep-wake clocks are synchronized to the day-night cycle through light exposure(and indeed, without it aren't even 24h-long), and have broad implications for mood, wakefulness, metabolism, and general health. I well might have seen something about cardiovascular problems specifically, though I don't remember.
I've also read somewhere that even the US Navy is changing to blue in their ships for some readability reasons.
Wondering how much of this is due to geography and air quality. City centers have relatively bad air quality and a high amount of ambient lighting at night, compared to non urbanized areas.
The cardiovascular effects of poor air quality is arguably well understood.
Is this a medical condition that has a name?
Is this one of those things where some element is considered desirable in the Western world (e.g. warm white lighting) but is associated with destitution in another culture (because it’s like incandescent lighting)?
But they already deconfounded for shift workers, so that's irrelevant. And they also showed the amount of light exposure for both night and day.
DNA adapts very quickly to such hard selectors, and many populations has lived in such areas for many thousands of years by now.
Worst thing is to wake up in total darkness in strange place. You dont remember were things are, cannot find the light switch, and start panicking, maybe I am gone blind?
The effect was also seen outside of the night worker population (13% of the population).
The paper concedes that shift work is unhealthy[1] but claims that shift work doesn't explain their finding[2]. And their conclusion is "avoiding night light may be a promising approach for preventing cardiovascular diseases," but without telling us why. It's going to be fascinating if there's a mechanism by which sleeping with light can cause heart disease.
[1] "Evidence demonstrates higher risks of adverse cardiovascular events, coronary heart disease, heart failure, atrial fibrillation, and mortality due to cardiovascular disease in rotating shift workers."
[2] "Following separate adjustments for pre-existing diabetes, hypertension, high BMI, high cholesterol ratio, short, long, or inefficient sleep, and exclusion of shift workers, the relationships of night light with cardiovascular risks were attenuated but remained statistically significant for all outcomes except stroke."
I suspect everyone in the field already knows the top-level answer: light at night blunts the output of the circadian pacemaker (SCN), with all sorts of downstream effects including control of various hormones. So the levels will be different with light at night. "at night" means biological night. If someone consistently sleeps on some schedule with bright enough light during their awake time, and it's dark during their sleep time, it's fine.
I'm not in the field. I read up on it at one point at a shallow level and talked to some researchers about it informally.
There's more details further in the article[1].
[1] https://www.medrxiv.org/content/10.1101/2025.06.20.25329961v...
I see it constantly when a study comes out all of these statistics students come out of the wood work and say "Correlation doesn't mean causation" without any other thought.
The study clearly claims only a correlation and absolutely, correlations help focus attention to try and find causal links in the future.
However, I think you are just being triggered by past traumas, because nobody said that here.
In any case, light sensitivity and sleep patterns are well linked. If you live far away from the equator, you are dealing with pretty short nights half of the year. I lived in Helsinki for a while. That can really mess up your sleep though some people manage to adapt. There's a reason coffee is popular in places like
I currently live in Berlin. I sleep about 2-3 hours less in the summer than in the winter. Somehow that works for me. But it's really annoying to be wide awake at 6 when you've set your alarm for 8. I'm literally typing this on my laptop early morning on a Sunday. But it's light very early this time of year.
I've experimented with wearing sleep masks. They really work. But I find them slightly uncomfortable. What works better is just doing sane things like trying to live healthy. Less alcohol, more sport. Etc. Work stress can cause all sorts of issues with that.
That's not OK, I don't know a single person affected so (live in cca same latitude as Berlin). Have you tried some radical solutions like good window blinds or similar sun blocking mechanisms? I don't mean some cheap crap that still lets strips of light through, I mean full block. Of course if then some chopper or ambulance wakes you up regardless it doesn't matter.
These days I don't drink alcohol any more, which has done wonders for my sleep quality. Quitting alcohol works better than almost anything else you can do. Long summer nights of drinking beer in the park (which is one of the perks that Berlin has) are not that great for this. But still, I easily sleep to 9am in the winter and in the summer I usually am awake a lot earlier. I typically stay in bet for a bit.
Btw, did you take a D vitamin supplement and use a light therapy lamp in the mornings?
The dark/light situation never affected me that much. But I could definitely see it in people around me. People from further south have a hard time dealing with darkness. Insomnia is something to guard for.
The Finnish are famously one of the most happy people around. But they also have relatively high suicide rates that spike in spring when after a miserably long winter, the availability of light pushes some people over the edge. As I used to morbidly joke, "Finland is so happy because all the unhappy people keep killing themselves thus removing themselves from these surveils". The Finnish love dark humor like that. This got a chuckle out some of them.
Meanwhile, the fortunate outliers are more in the south: Cyprus, Greece, Liechtenstein, Türkiye, Italy and Luxembourg.
> People with the brightest nights (90-100th percentiles) had significantly higher risks of developing coronary artery disease (adjusted-HR range: 1.23-1.32), myocardial infarction (aHRs: 1.42-1.47), heart failure (aHRs: 1.45-1.56), atrial fibrillation (aHRs: 1.28-1.32), and stroke (aHRs: 1.28-1.30), compared to people with dark nights (0-50th percentiles).
> These relationships were robust after adjusting for established risk factors for cardiovascular health, including physical activity, smoking, alcohol, diet, sleep duration, socioeconomic status, and polygenic risk. Relationships of night light with risk of heart failure and coronary artery disease were stronger for women, and relationships of night light with risk of heart failure and atrial fibrillation were stronger for younger individuals in this cohort.
These relationships were *robust*.
The observed associations between nighttime light exposure and increased incidence of coronary artery disease, myocardial infarction, heart failure, atrial fibrillation, and stroke may be driven by complex and multifactorial pathways. These cardiovascular conditions can arise from numerous interrelated long- and short-term physiological and behavioral factors, making it difficult to isolate the causal role of nighttime light exposure alone.
It is plausible to hypothesize that if individuals in the lower-exposure group were subjected to increased nighttime light exposure under controlled conditions—where all other lifestyle factors remained constant and stress levels were actively managed—their cardiovascular risk might not increase. This would suggest that ambient light exposure at night, in isolation, may not be a direct etiological factor.
Although the study adjusted for a broad range of established cardiovascular risk factors—including physical activity, smoking, alcohol consumption, diet, sleep duration, socioeconomic status, and polygenic risk—these adjustments do not capture acute or chronic variations in psychological stress. Since stress is a known contributor to cardiovascular disease, the inability to directly account for its temporal dynamics represents a potential limitation in the interpretation of these findings.
My cardiologist always asks about sleep, isn't it obvious a darker room makes for better sleep
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