It might be.
Research suggests an association between sleep restriction and negative changes in metabolism. In adults, sleeping four hours a night, compared with 10 hours a night, appears to increase hunger and appetite — in particular for calorie-dense foods high in carbohydrates. Observational studies also suggest a link between sleep restriction and obesity. Other studies have found similar patterns in children and adolescents.
One explanation might be that sleep duration affects hormones regulating hunger — ghrelin and leptin. Another contributing factor might be that lack of sleep leads to fatigue and results in less physical activity.
So now you have another reason to get a good night's sleep.