Pick the direction
If you want to wake and sleep earlier, choose a realistic target and move the wake time gradually, about 15–30 minutes every few days. Keep the wake time steady, including weekends, rather than chasing a single perfect night.
Use light as the cue
Seek outdoor light after waking, when possible. Reduce bright light in the hours before bed. Morning light tends to shift the body clock earlier; evening bright light tends to shift it later. Timing matters, especially for shift work and unusually early waking.
Support the shift
Keep meals, activity and bedtime routines reasonably regular. Avoid late caffeine. If you work nights, have a circadian rhythm disorder, take photosensitizing medicines or have bipolar disorder, ask a clinician before using bright-light devices or a prescribed timing protocol.
Original sources
- CDC/NIOSH: Effects of Light on Circadian Rhythms ↗
- NHLBI: Sleep/Wake Cycle ↗
- NHLBI: Healthy Sleep Habits ↗
Educational guidance. Adjust for your needs and seek professional care for persistent symptoms or a medical condition.