Research

Energy balance

Five days of insufficient sleep (5 hours/night) increases total daily energy expenditure by approximately 5% but leads to a net positive energy balance and weight gain because ad libitum food intake increases by ~6%, disproportionately driven by post-dinner snacking.

If you consistently sleep only 5 hours a night, you will likely gain weight even if you don't feel hungrier. Your body burns slightly more calories, but you eat significantly more, especially late at night. To prevent this, prioritize getting 7-9 hours of sleep, as it naturally reduces the drive to overeat, particularly carbohydrates and fats.

StrongSupportsVERY_HIGH confidence
We found that insufficient sleep increased total daily energy expenditure by ~5%; however, energy intake—especially at night after dinner—was in excess of energy needed to maintain energy balance. Insufficient sleep led to 0.82 ± 0.47 kg (±SD) weight gain...
Rachel R. Markwald et al. · Proceedings of the National Academy of Sciences · 2013

Why this rating

Randomized crossover design with whole-room calorimetry and ad libitum feeding in a controlled clinical setting.

Source

Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain

Rachel R. Markwald et al. · Proceedings of the National Academy of Sciences · 2013

DOI 10.1073/pnas.1216951110

crossover · n=16Cited 801×
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DOI resolved against Crossref · corpus check 2026-06-10

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