In women with overweight or obesity, early time-restricted eating (8:00–16:00) results in a modestly greater weight loss than late time-restricted eating (13:00–21:00) under isocaloric conditions, with a spontaneous daily caloric deficit of 167 kcal, indicating that early eating facilitates reduced energy intake in real-world settings.

When eating is limited to the morning and early afternoon, the body naturally eats less food throughout the day because hunger signals drop earlier and later meals are skipped. This happens because the internal body clock adjusts to food intake timing, which changes when the brain feels hungry and when it feels full, leading to fewer calories consumed without any effort to restrict food.