Given that the circadian clock regulates a wide range of physiological processes, it is no surprise that circadian misalignment in the form of social jet lag has been linked with various (potentially) negative health conditions, such as increased resting heart rate and cortisol levels [64,65], obesity [24], depression [25] and an adverse metabolic profile [66]. This evidence concerns the gene CLOCK and obesity due to melanocortin 4 receptor deficiency.