Research
Hormonal
Circadian rhythmicity and sleep independently and additively decrease glucose tolerance, with the combined effect of nighttime sleep and circadian timing causing the lowest glucose tolerance of the 24-hour cycle.
Your body's ability to regulate blood sugar drops significantly during sleep, even if you aren't eating. This is due to both the time of day (circadian rhythm) and the act of sleeping itself. Prioritizing good sleep hygiene helps maintain stable glucose levels overnight.
StrongSupportsHIGH confidence
The quantitative analysis of the size of the elevations seen in the absence of sleep and during daytime sleep suggests that, in normal conditions of nocturnal sleep, the effects of circadian rhythmicity and sleep are superimposed.
Why this rating
Based on controlled sleep-deprivation studies (Refs 23, 40).
Source
Roles of Circadian Rhythmicity and Sleep in Human Glucose Regulation*
Eve Van Cauter et al. · Endocrine Reviews · 1997
DOI 10.1210/edrv.18.5.0317
narrative_reviewCited 580×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
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