Research

Hormonal

Sleep restriction (4-5 hours/night) impairs glucose metabolism and insulin sensitivity to levels similar to those seen in pre-diabetic or diabetic populations.

Chronic sleep restriction (4-5 hours/night) can impair your body's ability to regulate blood sugar to levels seen in pre-diabetic individuals. This happens even if you maintain a healthy weight. Prioritize 7-9 hours of sleep to protect your long-term metabolic health and reduce your risk of type 2 diabetes.

GoodSupportsHIGH confidence
In a seminal study by Spiegel and colleagues, restricting sleep to a 4-h opportunity per night for six nights was found to decreased glucose clearance by 40% and the acute insulin response to glucose by 30% during a frequently sampled intravenous glucose tolerance test (IVGTT), similar to levels observed in diabetic populations (60).
Andrew W. McHill et al. · Obesity Reviews · 2017

Why this rating

Based on multiple controlled human studies showing consistent impairment in glucose tolerance and insulin sensitivity.

Source

Role of sleep and circadian disruption on energy expenditure and in metabolic predisposition to human obesity and metabolic disease

Andrew W. McHill et al. · Obesity Reviews · 2017

DOI 10.1111/obr.12503

narrative_reviewCited 309×
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DOI resolved against Crossref · corpus check 2026-06-10

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