Possible causes
- "Tired but wired" – stress and evening rumination keep the sympathetic nervous system activated.
- Shifted circadian rhythm – little daylight and lots of evening light push melatonin release later.
- Caffeine – its effect lasts many hours, so an afternoon coffee can affect falling asleep.
- Irregular schedule – different sleep times on weekdays and weekends act like a small jet lag.
- Restless legs – an urge to move the legs in the evening is often linked to low ferritin.
- Hormonal and health factors – an overactive thyroid, perimenopause, pain or certain medications.
What to check
- Sleep diary – bedtime, time to fall asleep, caffeine, screens and stress over two weeks.
- Ferritin – especially with restless legs; low levels can be addressed in a targeted way.
- TSH – if you also have palpitations, weight loss or sweating.
- Vitamin D and magnesium – deficiencies are common and relate to overall recovery.
What helps
- Morning light, evening dimness – get outside as soon as possible after waking; dim, warm light for the last two hours before bed.
- Caffeine only in the morning – have your last coffee roughly by noon.
- Same wake-up time – even after a bad night, so sleep pressure builds naturally by evening.
- A wind-down ritual – 30–60 minutes without work or news, a warm shower, reading, writing thoughts down on paper.
- Slow breathing – a few minutes of breathing with a long exhale calms the nervous system.
When to see a doctor
See a doctor if difficulty falling asleep lasts more than three months, significantly affects your day, or if you have restless legs, palpitations, unexplained weight loss, anxiety or low mood. For chronic insomnia, cognitive behavioural therapy for insomnia is an effective treatment.