Role of Sleep Timing in Caloric Intake and BMI

Abstract

Sleep duration has been linked to obesity and there is also an emerging literature in animals demonstrating a relationship between the timing of feeding and weight regulation. However, there is a paucity of research evaluating timing of sleep and feeding on weight regulation in humans. The goal of this study was to evaluate the role of sleep timing in dietary patterns and BMI. Participants included 52 (25 females) volunteers who completed 7 days of wrist actigraphy and food logs. Fifty‐six percent were “normal sleepers” (midpoint of <5:30 am) and 44% were “late sleepers” (midpoint of sleep ≥5:30 am). Late sleepers had shorter sleep duration, later sleep onset and sleep offset and meal times. Late sleepers consumed more calories at dinner and after 8:00 pm, had higher fast food, full‐calorie soda and lower fruit and vegetable consumption. Higher BMI was associated with shorter sleep duration, later sleep timing, caloric consumption after 8:00 pm, and fast food meals. In multivariate models, sleep timing was independently associated with calories consumed after 8:00 pm and fruit and vegetable consumption but did not predict BMI after controlling for sleep duration. Calories consumed after 8:00 pm predicted BMI after controlling for sleep timing and duration. These findings indicate that caloric intake after 8:00 pm may increase the risk of obesity, independent of sleep timing and duration. Future studies should investigate the biological and social mechanisms linking timing of sleep and feeding in order to develop novel time‐based interventions for weight management.

Impact of circadian misalignment on energy metabolism during simulated nightshift work

“…This decreased TEF may represent a contributing mechanism underlying the reported risk of weight gain associated with evening food intake. For example, food consumed past 2000 hours predicts higher body mass index (BMI) when controlling for sleep duration and timing (22), and night eating syndrome, a disorder in which individuals consume ≥25% of calories after their evening meal (23), is associated with a higher BMI (24). Reduced TEF after the late dinner is consistent with prior findings of an acute decrease in TEF after a meal consumed at 0100 hours compared with 0900 hours or 1700 hours (25).…”

“…Further, if increased exhaustion and fatigue levels (27) associated with shiftwork results in reduced physical activity levels, this would promote positive energy balance and weight gain. The decrease in TEF observed after a late meal applies to shiftworkers and also to day workers who eat later at night and have a higher risk of obesity (22). Further research is needed to extend current findings to include all components of energy balance, in particular the effects of dietary choices and timing of meals on risk of obesity in shiftworkers.…”

Impact of insufficient sleep on total daily energy expenditure, food intake, and weight gain

“…We also found participants ate smaller breakfasts during sleep loss. Our findings add to the growing body of evidence from epidemiological (26) and nonhuman models (27,28) that indicate that overeating at night may contribute to weight gain.…”

Interactions between endocrine and circadian systems

“…Symptoms of jetlag include decreased alertness, motor coordination and cognitive performance, sleep disturbances, gastrointestinal disruption, and loss of appetite (Waterhouse et al 2005). Sleep restriction and daytime sleep -hallmarks of a night shift work scheduleare associated with increased BMI and risk of metabolic syndrome, and alterations in circulating endocrine parameters such as insulin, glucose, and GCs (Wu et al 2008, Rehman et al 2010, Baron et al 2011. Cortisol rhythms are also affected by jet travel, even when only three or fewer time zones are crossed (Doane et al 2010), as well as by relatively subtle advances in sleep timing (Dijk et al 2012).…”