Light Sleep Stage
% of sleep time
Percentage of sleep time in light Non-REM sleep (N1 and N2), the transitional and consolidating phases between wakefulness and deep sleep.
Typical optimal range 45% - 55%
Population median 52%
Key factors
- Sleep environment noise and temperature
- Napping behavior
- Overall sleep pressure and fatigue accumulation
What affects this metric
- Apnea events and noise shift time out of deep and REM into light sleep.
- Light sleep expands when deep and REM are suppressed.
- Fragmented nights shift time into light sleep.
- It rises naturally with age as deep sleep declines.
References
Peer-reviewed sources supporting the key factors, contributing factors, and typical optimal range shown above.
- Ohayon MM, Carskadon MA, Guilleminault C, Vitiello MV. Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals. Sleep. 2004;27(7):1255–1273. doi.org/10.1093/sleep/27.7.1255
- Kapur VK, Auckley DH, Chowdhuri S, et al.. Clinical practice guideline for diagnostic testing for adult obstructive sleep apnea: an American Academy of Sleep Medicine clinical practice guideline. Journal of Clinical Sleep Medicine. 2017;13(3):479–504. doi.org/10.5664/jcsm.6506
- Okamoto-Mizuno K, Mizuno K. Effects of thermal environment on sleep and circadian rhythm. Journal of Physiological Anthropology. 2012;31:14. doi.org/10.1186/1880-6805-31-14
This guide is general information, not medical advice. Talk to your clinician about your own results.