Why can I not sleep?
Not a diagnosis: a head start. These are the three drivers most worth checking first, based on what the evidence says gets missed most often.
The 3am wake-up
Often a blood sugar dip triggering cortisol. A protein-heavier dinner is the cheap experiment.
Cortisol timing
Stress hormone peaking at night instead of morning flips your rhythm. Screens and late work feed it.
Alcohol’s false friend
It knocks you out, then wrecks the second half of the night. Track it honestly.
HbA1c, thyroid; track caffeine, alcohol and timing in a journal first
1. Start a two-minute note so the pattern becomes visible.
2. Take the test list above with you so you can explain the pattern clearly.
3. Read the evidence: Melatonin for Sleep: Evidence, Dosing and the UK Rules.
Education, not diagnosis, and never a replacement for your GP or pharmacist. Reference ranges and guidance vary; sudden, severe or worsening symptoms need 111, or 999 in an emergency. By Hussain Sharifi · independent, affiliate-free health research.