Disturbances of sleep and circadian rhythms: novel risk factors for obesity

Abstract

Purpose of review To summarize recent developments linking disturbances of sleep and circadian rhythms to an increased risk for obesity, and to review novel research on potential countermeasures. Recent findings Effective treatments for obesity are limited, with long-term adherence to life style changes proving difficult. Identifying new preventive strategies based on modifiable risk factors is therefore imperative in the fight against obesity. Disturbances of sleep and circadian rhythms have an adverse impact on food choices, hunger and appetite and have lifelong deleterious metabolic effects when present during childhood and early adulthood. The upregulation of the endocannabinoid system and abnormalities in the temporal distribution of caloric intake have been recently implicated in the link between sleep loss and obesity risk. Lastly, alterations in the circadian variation in the composition and functionality of the gut microbiome have been identified as potential contributors to metabolic dysfunction in conditions of jet lag and shift work. Insufficient sleep and circadian misalignment are thus new modifiable risk factors for obesity. Emerging evidence suggests that novel countermeasures, such as manipulations of the timing of food intake, may be effective strategies in the prevention of obesity. Summary Four important findings are briefly reviewed: 1. disturbances of sleep and circadian rhythms in children and young adults are risk factors for the development of lifelong obesity; 2. circadian misalignment, as occurs in shift work, has an adverse impact on energy balance and increases the risk of weight gain; 3. the endocannabinoid system, an important regulator of hedonic feeding, could be a potential link between sleep, circadian rhythms and feeding behavior; 4. disturbances of the circadian variation in composition of the gut microbiome could be involved in the increased risk of obesity associated with insufficient sleep and circadian misalignment.

Shift Work: Disrupted Circadian Rhythms and Sleep—Implications for Health and Well-being

“…Recent work indicates that the gut microbiome shows diurnal variations that are influenced by meal times and disturbed by circadian misalignment [40]. The gut microbiome both responds and contributes to host energy balance, and disruption is associated with inflammation, insulin resistance, and adiposity [41].…”

School Start Time and the Healthy Weight of Adolescents

“…Interventions that target healthy weights have traditionally focused on promoting physical activity and healthy eating, but emergent research shows that sleep is an additional health behavior that influences body weight in youth [6,7]. In a recent systematic review of 22 longitudinal studies, Fatima et al [8] found that children and adolescents who had a short sleep duration had twice the odds of overweight or obesity compared to those with longer sleep (odds ratio [OR] 2.15, 95% confidence interval [CI] 1.64, 2.81).…”

The association of self-reported sleep quality and obesity in Kuwait using the Pittsburgh Sleep Quality Index (PSQI)

“…Though the underlying mechanisms linking poor sleep quality and obesity are still unclear, it is believed that sleep disturbance and poor sleep quality leads to several alterations in body metabolism and the endocrine system. In particular, the stress response hormones such as ghrelin, cortisol and leptin are shown to be upregulated in sleep-deprived individuals (15, 29). These hormones play a major role in not only maintaining energy balance at cellular levels, but also influence food preference and are associated with increased food intake.…”