Research

Energy balance

Short sleep duration (defined as <7 hours per night) is consistently associated with an increased risk of developing obesity and type 2 diabetes mellitus (T2DM) in adults and children, with a dose-response relationship where shorter sleep correlates with higher risk.

Aim for 7-8 hours of sleep per night. Consistently getting less than 7 hours is a significant risk factor for gaining weight and developing type 2 diabetes. This is not just about feeling tired; it affects your body's energy balance and insulin sensitivity. Protecting your sleep duration is as critical for metabolic health as your diet and exercise habits.

GoodSupportsHIGH confidence
Based to cohort-included meta-analytic data, short sleep duration has been consistently associated with increased risk of obesity (whether defined based on BMI or WC)... The shorter the sleep duration, the higher the risk of obesity; the pooled relative risk (RR) for obesity was 1.09 (95% CI, 1.05–1.14) per 1-h decrement of sleep duration compared to 7–8 h (Itani et al. 2017, Zhou et al. 2019).
Christina Antza et al. · Journal of Endocrinology · 2021

Why this rating

Based on multiple large-scale meta-analyses of cohort studies with sample sizes ranging from 15,000 to 200,000 participants.

Source

The links between sleep duration, obesity and type 2 diabetes mellitus

Christina Antza et al. · Journal of Endocrinology · 2021

DOI 10.1530/joe-21-0155

narrative_reviewCited 262×
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DOI resolved against Crossref · corpus check 2026-06-10

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