Research

Hormonal

Sleep restriction (4 hours/night) impairs glucose tolerance and increases post-breakfast insulin resistance, as measured by elevated HOMA values, despite similar insulin levels to rested conditions.

Sleeping only 4 hours makes your body handle carbohydrates poorly the next morning, leading to higher blood sugar spikes. This happens even if you eat the same amount of food. Prioritize sleep to maintain good glucose tolerance.

GoodSupportsHIGH confidence
Postbreakfast HOMA was significantly elevated (+56%) when the subjects were in a state of sleep debt, compared with fully rested... glucose levels during the first 90 min were higher during sleep restriction than sleep extension, despite insulin levels that were slightly, but not significantly, higher.
Karine Spiegel et al. · The Journal of Clinical Endocrinology & Metabolism · 2004

Why this rating

Controlled crossover design with oral glucose tolerance testing components.

Source

Leptin Levels Are Dependent on Sleep Duration: Relationships with Sympathovagal Balance, Carbohydrate Regulation, Cortisol, and Thyrotropin

Karine Spiegel et al. · The Journal of Clinical Endocrinology & Metabolism · 2004

DOI 10.1210/jc.2004-1003

crossover · n=11Cited 998×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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