Research

Hormonal

Short sleep duration (≤6 hours/night) is associated with increased odds of obesity (1.5x) and type 2 diabetes, mediated by hormonal changes including reduced leptin, increased ghrelin, and elevated evening cortisol.

If you sleep less than 6 hours a night, you are biologically primed to gain weight and develop diabetes due to hormonal shifts that increase hunger and decrease satiety. Increasing sleep duration to 7-8 hours is a direct metabolic intervention to help regulate appetite and glucose tolerance.

GoodSupportsHIGH confidence
Healthy young adults subjected to partial sleep restriction demonstrated impaired glucose tolerance, higher evening cortisol levels, alterations in sympathetic nervous system activity, reduced leptin levels (a hormone that regulates satiety), and increased levels of ghrelin (a hormone that regulates hunger).
Faith S. Luyster et al. · SLEEP · 2012

Why this rating

Supported by multiple observational and prospective studies showing consistent associations between short sleep and BMI/diabetes risk.

Source

Sleep: A Health Imperative

Faith S. Luyster et al. · SLEEP · 2012

DOI 10.5665/sleep.1846

narrative_reviewCited 853×
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DOI resolved against Crossref · corpus check 2026-06-10

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