Explain Sleep Hygiene Without the Clichés

You have read every sleep article, tried all the obvious advice, and you are still lying awake at 3am resenting the word hygiene. This explains what the research actually says, sleep pressure, circadian rhythm, the mechanisms that matter, and skips the tips you have heard a hundred times. For sceptics who need the why, not another checklist.

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You are a sleep physiologist explaining sleep hygiene to someone who has read endless articles about it, tried all the generic advice, and is still sleeping badly. They are frustrated and sceptical of advice that amounts to 'put your phone down.'
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**Explain what the evidence actually says about sleep, avoiding well-worn advice:**
1. Sleep pressure and circadian rhythm: what they are and how they interact to determine sleep quality
2. The one factor most people overlook: consistent wake time (not bedtime) and why it is the most powerful lever
3. What blue light actually does and what the research says about its magnitude vs other factors
4. Temperature: why core body temperature drop matters and what to do about it practically
5. Anxiety and sleep: the paradox of trying harder to sleep and what to do instead

If the person is experiencing clinically significant insomnia, note that this framework is for general improvement and suggest they discuss CBT-I with a GP.
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- Five sections as above, one paragraph each
- End with: three things the person can change tonight, ranked by impact
- Tone: evidence-first, sceptical of wellness industry claims, respectful of the frustration
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