It should be no surprise, that it is not good for your health, if you do not sleep well. So fixing whatever it is preventing you from good sleeping really should be priority number 1 if you want to maintain or restore your health.
Easier said than done, of course, but reducing coffeine, doing more sports and avoid bringing the smartphone into your bedroom would probably be a good start.
Yeah, I have been trying to do that for many years, because obviously poor sleep has plenty of bad outcomes, not only long-term but also including immediately obvious ones.
But for some of us, it's hard. I have taken measures like exercising, having dinner earlier, trying to read for a while before going to bed, etc. and they do help somewhat, but the truth is I seem to be too sensitive to stress. When a backlog of tasks accumulates (which, in my job, is most of the time) I start ruminating about work in bed, sometimes this gets compounded by gas and reflux (I once thought this was about food, but no, I have long found out that it's totally about stress, if I'm on holiday I can eat like a horse and never get gas and if I'm stressed I can get it from pretty much anything) and there goes my night's sleep.
My work is pretty stressful (and hard to reduce the workload) but I don't think I can just blame the job, as this happens even when the backlog isn't such a huge deal objectively speaking, and I can handle it. But it seems that I'm just bad at disconnecting from things. In fact for example if I have a morning flight the next day I always sleep like crap, not because I have any fear of flying at all, but my mind is just not at rest thinking what if the alarm clocks fail (which never happens), etc. I know it won't happen, but the thought keeps me awake anyway.
I had some success with meditating and breathing exercises.
But mostly really doing everything, I possible could do, to reduce "open problems".
And developing a "don't care so much" attitude. The world likely won't burn, if I make misstakes. Shit happens. I do what I can.
"if I have a morning flight the next day I always sleep like crap, not because I have any fear of flying at all, but my mind is just not at rest thinking what if the alarm clocks fail"
And one time I actually forgot to set the alarm, but I still woke up exactly one minute before the alarm was supposed to wake me up ..
Hi, I've had the same experiences (ruminating about job when I should be sleeping), and listening to SF/fantasy audiobooks in bed seems to help a lot. If you're invested in the story, it stimulates your imagination and crowds out all the everyday worries.
For me, while it's true that work and other kinds of pressure are able to create the stress that causes bad sleep, I am perfectly capable of getting stressed for no reason at all.
The good news is that this seems to be getting better as I age.
People with treatment-resistant primary insomnia should go ahead and make their peace. If CBT-i, calming exercises, or the small stable of medications (all of modest efficacy and some themselves implicated in dementia among other risks) don't work for you, then there's not much that can be done.
We don't have very powerful tools to help with sleep, which is a damned shame seeing as insomnia is a consequence or cause of so many problems.
Easier said than done, of course, but reducing coffeine, doing more sports and avoid bringing the smartphone into your bedroom would probably be a good start.