Caffeine Curfew Audit
Move caffeine earlier and test a personal cutoff, starting at least 8 hours before bedtime for sensitive sleepers.
Dosage & Timing
Evidence Strength
4/5 — StrongControlled trials show caffeine can impair sleep even when taken several hours before bed.
Overview
Move caffeine earlier and test a personal cutoff, starting at least 8 hours before bedtime for sensitive sleepers.
How To Do It
Step 1
Write down your usual bedtime.
Step 2
Set caffeine cutoff 8 hours before that target bedtime.
Step 3
Keep the morning dose stable while testing the cutoff.
Step 4
Compare sleep latency and awakenings after 10 nights.
The Evidence
Each claim is linked to its source study. Confidence reflects the study design — systematic reviews and RCTs rank highest.
Caffeine effects on sleep taken 0, 3, or 6 hours before going to bed↗
Caffeine consumed even 6 hours before bedtime produced measurable sleep disruption.
Primary Literature
Interactions & Warnings
Contraindications
- ⚠Caffeine withdrawal headaches
- ⚠Pregnancy or medication guidance requiring clinician review
Interactions
- •Supports blue light reduction and sleep diary protocols
Measurable Outcomes
Related Protocols
Caffeine Curfew
No caffeine after ~2pm (for 10pm bedtime). Caffeine's 5-6 hour half-life means afternoon intake significantly reduces deep sleep even if you fall asleep fine.
Morning Sunlight Exposure
View bright light within 60 minutes of waking to set your circadian clock. This triggers a cortisol pulse and starts a timer for melatonin release 14-16 hours later.
Blue Light Reduction
Dim lights and avoid screens 2-3 hours before bed to protect melatonin production. Use warm/amber lighting and blue-light blocking glasses if screen use is unavoidable.
Sleep Temperature Optimization
Keep your bedroom at 65-68°F and take a warm shower 1-2 hours before bed. Core temperature drop is a key trigger for sleep onset and deep sleep.