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Does sleep deprivation cause weight gain?

Last updated: October 15, 2026

Yes. Short sleep is associated with weight gain through multiple mechanisms: increased ghrelin (hunger hormone), decreased leptin (satiety hormone), and impaired glucose regulation.

The hormone shifts

In a lab study, two nights of 4 hours in bed raised ghrelin by 28%, lowered leptin by 18% and increased hunger by 24% in healthy young men (Spiegel et al., 2004). In a population study, people who habitually slept 5 hours had about 15% lower leptin and 15% higher ghrelin than 8-hour sleepers (Taheri et al., 2004). The result: more hunger, less satisfaction from meals.

Food choices

In the same lab study, appetite for calorie-dense, high-carbohydrate foods rose by 33 to 45% (Spiegel et al., 2004). Brain-imaging studies also suggest that sleep loss makes high-calorie food more tempting.

Population data

A meta-analysis of mostly cross-sectional studies covering more than 600,000 adults found that short sleepers had about 55% higher odds of obesity (Cappuccio et al., 2008). These are associations: they do not prove that short sleep alone causes the weight gain.

Sources

1. Spiegel et al., Annals of Internal Medicine, 2004. Sleep curtailment in healthy young men is associated with decreased leptin levels, elevated ghrelin levels, and increased hunger and appetite
2. Taheri et al., PLoS Medicine, 2004. Short sleep duration is associated with reduced leptin, elevated ghrelin, and increased body mass index
3. Cappuccio et al., Sleep, 2008. Meta-analysis of short sleep duration and obesity in children and adults