it's not a thing to go to the doctor and request various tests, here.
Well, it's a function of the relationship between you and your doctor. You certainly can ask for tests and while it could be true that an NHS doctor will be less likely to agree to them than a US doctor, you don't lose anything by asking.
Of course, saying "sometimes I feel a bit tired" is one thing, and saying (still quoting you) "...am often extremely dozy by mid-afternoon ... I just... feel tired when I do so. And during the day. And really, really tired at night." is quite a different thing.
The tired-by-mid-afternoon feeling, by the way, could indicate sugar control problems. I'd add fasting glucose test to the general blood panel -- if you are pre-diabetic, you really want to know this.
The tired-by-mid-afternoon feeling, by the way, could indicate sugar control problems.
The normal circadian rhythm has two low points, the other one in the afternoon. A dip in alertness at that time is probably normal.
I'd like to have a series of discussion posts, where each post is of the form "Let's brainstorm things you might consider when optimizing X", where X is something like sleep, exercise, commuting, studying, etc. Think of it like a specialized repository.
In the spirit of try more things, the direct benefit is to provide insights like "Oh, I never realized that BLAH is a knob I can fiddle. This gives me an idea of how I might change BLAH given my particular circumstances. I will try this and see what happens!"
The indirect benefit is to practice instrumental rationality using the "toy problem" provided by a general prompt.
Accordingly, participation could be in many forms:
* Pointers to scientific research
* General directions to consider
* Personal experience
* Boring advice
* Intersections with other community ideas, biases
* Cost-benefit, value-of-information analysis
* Related questions
* Other musings, thoughts, speculation, links, theories, etc.
This post is on sleep and circadian rhythms.