Less than 6 hours of sleep a night linked to increased risk of early death
nhs.uk
nhs.uk
How is this even treated as a serious study?
Also "However, various health and lifestyle factors could be playing a role in the links they identified."
I imagine that if someone is poor (on average) they'd get less sleep due to living in noisier areas, working longer hours and so on. I also imagine being poor would decrease life expectancy on average.
And another one I thought of ...
1990-2017 is not a long time. Older people (say >50) tend to sleep fewer hours. Older people are much more likely to die in a 30 year period than younger people (<30), so there is that. I wonder if that was taken into account.
One thing I'm curious about: if one views lifespan as a function of total waking hours, rather than age at death, is there a "sweet spot" where one breaks even, or even comes out ahead? Against an 8-hour baseline, perhaps 5 hours per night shortens lifespan by more than (3 hours * 365 days * $n years), but maybe at 7 hours per night, the reduction in average lifespan is compensated by the extra hour every day? (That doesn't mean it's desirable, in terms of QoL at retirement, living to see grandkids, etc.; just curious.)
I think if you could go into some kind of cryogenic stasis for twenty years without otherwise substantially shortening your waking hours, it would be a kind of no brainer.
Time spent choosing to do nothing (e.g. doing mindfulness meditation while lying eyes-closed on a hammock), with your brain fully engaged in doing nothing, would be "productive."
Time when your brain forces you to do nothing (sleeping, or even just "comfortably" dozing off); or when you do something poorly, because of brain fog or an inability to learn quickly; or when your executive functioning or memory screws up and you choose to do something that doesn't minimize regret among all the things you could equally-well have chosen to do—would all be "unproductive" time.
(Equally well, you would be "unproductive" when your body isn't doing what your brain tells it to do—though in most cases the answer there is to either choose your concrete goals to match your physical capabilities, or to work to increase those capabilities. Stephen Hawking's time was not unproductive. People with Chronic Fatigue Syndrome, though, mostly are unproductive, because their physiology gets in the way no matter what they choose to do.)
A fun—and, to me, oddly enlightening—analogy: on a CPU, productivity is a lot easier to measure. Electricity costs money; calculations can make you money. Thus, executing useful instructions is productive; while executing NOPs is unproductive. And the less electricity you use to execute the same code, the better. Sleep-states aren't as productive as executing useful code, but they're more productive than executing NOPs, insofar as NOPs cost you money that sleep-states don't. More useful instructions per second requires more cooling, and cooling requires electricity, so parallelism isn't necessarily more productive, just "faster" in some sense we don't necessarily care about. Etc. (Is there a name for this measure? Lifetime net operating profit of a given capital asset, as attenuated by different ways of employing it?)
Optimizing for lifetime area-under-the-curve "productivity" in this sense would be very interesting to me.
Any magic optimizing formula would certainly have to account for that subjective value. (Although, being tired can sometimes function as a desirable altered state of consciousness; it can be very satisfying to work on a creative project late into the night.)
Now at 30, if I get less than 8 hours of uninterrupted sleep a few days in a row, I'm a zombie and I feel the negative effect in all my activities: brain fog at work, depressed, no lust for social gatherings, sports or sex.
I've lived on 6 or less hours of sleep all my life, the only time I sleep longer is during a bad porphyria "attack", then it's like 19 hours at a time, but that's only several times a year.
Subsequently, my career choices accommodated it, I became an entrepreneur so I could set my own hours (like after Noon), and a 40 year career doing late night broadcast radio.
I've seen these "studies" so many times, all I can do is Laugh, oh, and keep on Living this way, and I've made it to 65, and still going, so hooey on those "studies".
I think I read that mammals more or less get the same number of heartbeats in a lifetime -- so Hummingbirds don't last so long but Elephants live a long time (due to slower heart rate vs very high heart rate for a Hummingbird). I suppose sleeping more might correlate to a lower average heart rate (and thus a longer life).
I'm not sure then what I'm supposed to take away from that study (Mail, not NHS).
Edit: I also want to include that reducing nicotine was one very large factor in me getting a better night's sleep. I found that due to constant smoking, my blood pressure was basically locked at a high rate for extended periods of time, which eventually caused my heart to palpitate during some nights. Reducing caffeine and lowering my smoking frequency made those issues vanish, and overrall, was a healthy choice to make regardless.
Edit: clarifications
The participants were literally examined using a single night's sleep pattern. This is dangerous "science".
Anybody who even remotely cares about sleep fitness should try one out.
> The natural explanation was that [...] People who have lots of problems in their lives are more stressed. Stress makes it harder to sleep at night. People who can’t sleep at night get sleeping pills. Therefore, sleeping pill users have more problems, for every kind of problem you can think of. When problems get bad enough, they kill you. This is why sleeping pill users are more likely to die of everything.
Obviously, you can also wind that one step back and find that "people who don't sleep well" also have more problems, for every kind of problem you can think of.
Basically, if your study says that taking Ambien doubles your risk of cancer, bubonic plague, dying in a plane crash (where you are not the pilot) and being shot by snipers, the study is probably wrong. Given that it's a drug taken for sleep difficulties, and the number of possible things that can cause sleep difficulties (near the top of the list: stress, from literally innumerable sources), and the fact that sleep difficulties take a medical toll, as well as do many of the primary, secondary, and tertiary causes of sleep difficulties, it's very hard to account for that in a study.
> ...
> However, its limitations mean that its findings are not conclusive.