
10/09/2025
Research shows that sleep duration has a huge impact on how your body processes food. In one study, participants sleeping only 5.5 hours per night lost 55% less fat and 60% more muscle compared to those sleeping 8.5 hours even when following the exact same diet.
Lack of sleep disrupts hormones like ghrelin and leptin, which control hunger and fullness, making you eat more than you need. It also raises cortisol levels, encouraging the body to store energy as fat, and promotes insulin resistance, which can further reduce muscle growth and repair. Simply put, poor sleep can turn your food into fat instead of fuel.
📚 Source: Nedeltcheva et al., Annals of Internal Medicine