Sleep optimisation
Hygiene basics, sleep stages, light/temperature/timing, tracking metrics — what the literature actually supports.
If you only read one
Alcohol and sleep: why a 'nightcap' is the wrong word
Alcohol shortens sleep latency but degrades the second half of the night, suppresses REM, and fragments sleep architecture. A look at what the research actually shows, dose-response, and how this shows up on wearables.
Grade A · 3 min read · Last reviewed 2026-05-18
Alcohol and sleep: why a 'nightcap' is the wrong word
Evidence AAlcohol shortens sleep latency but degrades the second half of the night, suppresses REM, and fragments sleep architecture. A look at what the research actually shows, dose-response, and how this shows up on wearables.
3 min read · Last reviewed 2026-05-18
Blue light reduction: what the lab studies actually measure
Evidence CBlue-blocking glasses, screen filters, and the claim that evening screens 'destroy melatonin' — what the controlled chronobiology research shows, and the effect sizes you should expect.
2 min read · Last reviewed 2026-05-17
CBT-I: the NICE first-line for insomnia (and why it works)
Evidence ACognitive Behavioural Therapy for Insomnia (CBT-I) is the NICE-recommended first-line treatment for chronic insomnia. How it differs from sleep hygiene, what the trials show, and how to access it on the NHS.
3 min read · Last reviewed 2026-05-19
Jet lag: a practical, research-backed protocol
Evidence BLight exposure timing is the most powerful free intervention for adjusting to a new time zone. A look at the phase-response curve, eastward vs westward asymmetry, and what to do day by day.
3 min read · Last reviewed 2026-05-19
Light, temperature, and timing: the three biggest sleep levers
Evidence AThe most-replicated environmental and behavioural levers for sleep — light exposure, bedroom temperature, and timing consistency — and the rough effect sizes the literature reports.
2 min read · Last reviewed 2026-05-17
Magnesium glycinate and sleep: what the research actually shows
Evidence CMagnesium glycinate is one of the most-recommended supplements for sleep online. The human evidence is thinner than the marketing — here's what's actually in the literature.
2 min read · Last reviewed 2026-05-17
Melatonin in the UK: a prescription-only medicine with limited evidence
Evidence AMelatonin is freely available over the counter in the US but a prescription-only medicine in the UK. What the research supports, what it doesn't, and the difference between licensed clinical use and over-the-counter assumption.
3 min read · Last reviewed 2026-05-19
Mouth taping: what the evidence actually shows
Evidence CMouth taping is a popular sleep optimisation claim — better sleep, nasal breathing, jaw shape. The published evidence is much smaller than the wellness market suggests, and the safety considerations are real.
3 min read · Last reviewed 2026-05-19
Naps: the research behind dose, timing, and sleep inertia
Evidence BHow long, when, and whether — what the published research says about nap dose, sleep inertia, the 'NASA nap', and why long afternoon naps may worsen night-time sleep.
3 min read · Last reviewed 2026-05-19
Sleep apnoea screening: what the wearables can and can't tell you
Evidence AObstructive sleep apnoea is under-diagnosed in the UK. STOP-BANG, wearable SpO2, and the NHS pathway — what's useful, what's misleading, and when to ask your GP for a sleep study.
3 min read · Last reviewed 2026-05-19
Sleep hygiene basics: what the literature actually supports
Evidence BA plain-English look at the sleep hygiene rules that hold up in research — consistent timing, light exposure, temperature, caffeine, and stimulus control — and the ones that don't.
2 min read · Last reviewed 2026-05-17
Sleep stages explained: NREM, REM, and what cycles look like
Evidence AWhat the four stages of sleep represent, how cycles change across the night, and what consumer wearables can and can't tell you about them.
2 min read · Last reviewed 2026-05-17
Sleep tracking metrics: what to pay attention to (and what to ignore)
Evidence BTotal sleep time, sleep efficiency, latency, and stage estimates — how reliable each metric is on consumer wearables, and which numbers are worth changing your behaviour over.
2 min read · Last reviewed 2026-05-17
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