Compound or practice · Sleep
Sleep architecture
The recovery system everything else compounds on — deep and REM timing matter more than raw hours.
- Overall grade
- Grade A
- Last revised
- 4
- graded outcomes
- 3
- references listed
A hand-written entry in Prometheus's bundled library. Its grades are the entry's own reading of the evidence, not a peer-reviewed review.
5 at grade A · 3 at grade B — 8 graded rows
What is known
Each outcome with its grade (how strong the evidence is, A to D), the size of the effect where the entry records one, and how often studies agree.
- Insomnia severity (CBT-I components)Evidence grade A
Beats hypnotics on durability in head-to-head trials
Largehigh
- Deep-sleep minutes (schedule consistency)Evidence grade A
Fixed wake time is the highest-leverage single habit
Moderatehigh
- Next-day cognitionEvidence grade A
Attention and working memory track sleep efficiency
Moderatehigh
- REM cost of evening alcoholEvidence grade A
Fragmentation visible on wearables at 2 drinks
Moderatehigh
Conditions
How the entry reads its effect on diagnosed conditions: the direction first, then the grade. Never a substitute for the person who treats you.
- Insomnia ImprovesEvidence grade AThe CBT-I framework is first-line treatment, ahead of medicationGrade A
- Depression ImprovesEvidence grade BBidirectional link; fixing sleep measurably lifts mood outcomesGrade B
- Hypertension ImprovesEvidence grade BShort sleep raises 24h blood-pressure loadGrade B
- Type 2 diabetes ImprovesEvidence grade BOne week of 5-hour nights measurably worsens insulin sensitivityGrade B
What is uncertain
Read off the same rows as above. Nothing here is added that the entry does not itself record.
- Watch with Caffeine + L-Theanine: Respect the 8–10h cutoff or the stack pays for itself in deep sleep
- Watch with Cold exposure: Evening immersion is arousing — morning slots only
Up: deep-sleep change %. Across: hours before bed. Same dose, different clock — the cutoff is the dose.
Up: sleep efficiency %. Across: weeks. The anchor habit compounding — this is the trend your Endocrine agent watches.
The evidence in words
What architecture means
A night is staged, not uniform: deep (slow-wave) sleep front-loads the first half — physical recovery, growth hormone, glymphatic clearance — while REM back-loads toward morning and does the emotional-memory work. Cutting a night short doesn't trim evenly; it amputates REM. That's why 6 hours feels worse than the math suggests.
What actually moves it
Wake-time consistency beats bedtime discipline — the circadian anchor is when you get up. Morning outdoor light advances the rhythm; bright light after 21:00 delays it. Core temperature has to fall to enter deep sleep (cool room, warm shower before bed works via rebound). Caffeine within 8h and alcohol within 3–4h of bed both measurably cut deep sleep — alcohol also fragments REM even at two drinks.
What to expect
Two to three weeks of a fixed wake time and light routine typically buys +3–5% sleep efficiency and more stable HRV. Subjective energy lags the wearable numbers by about a week — trust the trend, not the morning mood.
How it is used
As the entry records it, from the studies it summarises. Not a recommendation for you — doses that suit a trial population may not suit you.
- Anchor
- Fixed wake time ±30 min, all 7 days — the single highest-leverage habit in this article.
- Light
- 10 min of outdoor light within an hour of waking; dim, warm light after 21:00.
- Cutoffs
- Caffeine 8–10h, alcohol 3–4h, hard training 3h before bed. Cool room (~18–19°C).
Goes with
- Magnesium L-ThreonateThe supplement layer on top of the behavioral baseEvidence grade B
- AshwagandhaWhen the insomnia is cortisol-driven, treat the stress floor tooEvidence grade B
Questions people ask
Do naps break it?
≤20 minutes before 15:00 is neutral-to-positive for most people. Long or late naps eat the same sleep pressure your night runs on.
Can I catch up on weekends?
Partially at best — and the rhythm shift ('social jetlag') usually costs more than the extra hours repay. The fix is the weekday schedule, not the weekend rescue.
Related reading
Entries that share this one's tags or conditions.
- Tart CherryA natural melatonin-and-anthocyanin source with small sleep and exercise-recovery signals.Evidence grade C
- ApigeninThe chamomile flavone behind the bedtime-tea calm — mild, benign, thinly studied as an isolated supplement.Evidence grade C
- L-Tryptophan / 5-HTPSerotonin/melatonin precursors with modest sleep-and-mood signals — and the sharpest serotonergic-drug caution on the shelf.Evidence grade C
- Magnolia Bark for SleepEvidence grade C — EarlyEvidence grade C
Sources
As this entry records them: title, journal and year. None carries a DOI or PubMed id, so none is linked as a verified paper. Each link searches PubMed for the title; check that what you find is what the entry describes.
- 1.Cognitive behavioral therapy vs pharmacotherapy for chronic insomnia — JAMA Intern Med, 2015. Search PubMed (opens in a new tab)
- 2.Sleep duration and all-cause mortality: meta-analysis — Sleep, 2010. Search PubMed (opens in a new tab)
- 3.Acute sleep restriction and insulin sensitivity in healthy adults — Ann Intern Med, 2012. Search PubMed (opens in a new tab)
Last revised . A grade is this entry's reading of the evidence, not medical advice.