Research

Hormonal

Sleep curtailment (4 hours/night for 2 nights) in healthy young men significantly decreases leptin levels, increases ghrelin levels, and increases hunger and appetite, particularly for calorie-dense, high-carbohydrate foods.

If you are trying to manage your weight, prioritize getting enough sleep. Restricting sleep to 4 hours for just two nights can significantly increase your hunger and cravings for high-calorie, high-carb foods by altering your hunger hormones. This is not just willpower; it is a biological response to sleep loss.

GoodSupportsHIGH confidence
Sleep restriction was associated with average reductions in the anorexigenic hormone leptin (decrease, 18%; P < 0.04), elevations in the orexigenic factor ghrelin (increase, 28%; P < 0.04), and increased hunger (increase, 24%; P < 0.01) and appetite (increase, 23%; P < 0.01), especially for calorie-dense foods with high carbohydrate content (increase, 33% to 45%; P < 0.02).
Karine Spiegel et al. · Annals of Internal Medicine · 2004

Why this rating

Randomized crossover design with controlled caloric intake, but small sample size (n=12) and short duration.

Source

Brief Communication: Sleep Curtailment in Healthy Young Men Is Associated with Decreased Leptin Levels, Elevated Ghrelin Levels, and Increased Hunger and Appetite

Karine Spiegel et al. · Annals of Internal Medicine · 2004

DOI 10.7326/0003-4819-141-11-200412070-00008

crossover · n=12Cited 2,428×
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DOI resolved against Crossref · corpus check 2026-06-10

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