How sleep restriction shifts appetite hormones and appetite itself toward overeating.
What the evidence says
- Sleep restriction decreases leptin by 18% and increases ghrelin by 28%, in 12 healthy young men given 2 days of sleep restriction ”under controlled conditions of caloric intake and physical activity”. Under free intake, a five-day study found that ”Insufficient sleep led to 0.82 ± 0.47 kg (±SD) weight gain despite changes in hunger and satiety hormones ghrelin and leptin, and peptide YY, which signaled excess energy stores”[1],[2]
- Appetite ratings rose 23%. The study held intake constant by design and measured no consumption[1]
- Appetite for calorie-dense, high-carb foods increases 33-45% with sleep restriction[1]
- The authors’ own stated limitation: ”The study included only 12 young men and did not measure energy expenditure.” It measured hormones and subjective ratings of hunger and appetite, not intake, expenditure or weight, so it cannot speak to energy balance or to weight gain[1]