Energy Balance and Control of Body Weight: Possible Effects of Meal Timing and Circadian Rhythm Dysregulation.

Alessio Basolo,Jonathan Krakoff,Susanna Bechi Genzano,Ferruccio Santini,Paolo Piaggi

doi:10.3390/nu13093276

Abstract

Conservation of the energy equilibrium can be considered a dynamic process and variations of one component (energy intake or energy expenditure) cause biological and/or behavioral compensatory changes in the other part of the system. The interplay between energy demand and caloric intake appears designed to guarantee an adequate food supply in variable life contexts. The circadian rhythm plays a major role in systemic homeostasis by acting as “timekeeper” of the human body, under the control of central and peripheral clocks that regulate many physiological functions such as sleep, hunger and body temperature. Clock-associated biological processes anticipate the daily demands imposed by the environment, being synchronized under ideal physiologic conditions. Factors that interfere with the expected demand, including daily distribution of macronutrients, physical activity and light exposure, may disrupt the physiologic harmony between predicted and actual behavior. Such a desynchronization may favor the development of a wide range of disease-related processes, including obesity and its comorbidities. Evidence has been provided that the main components of 24-h EE may be affected by disruption of the circadian rhythm. The sleep pattern, meal timing and meal composition could mediate these effects. An increased understanding of the crosstalk between disruption of the circadian rhythm and energy balance may shed light on the pathophysiologic mechanisms underlying weight gain, which may eventually lead to design effective strategies to fight the obesity pandemic.

Highlights

Obesity is a growing public health problem and an ever-increasing global pandemic with individual and general consequences
By measuring oxygen consumption and carbon dioxide production, the respiratory chamber provides a precise estimation of the energy expended by a human subject every minute over long periods of time. This method is considered the gold standard for the measurement of energy expenditure over 24 h because of the ability to distinguish the daily components of energy expenditure such as resting metabolic rate (RMR), thermic effect of food (TEF) and the energy cost of physical activity (PA)
Emerging evidence suggests that higher caloric intake in the morning than later during the day is associated with reduced susceptibility to weight gain, further controlled intervention trials are needed to provide definitive conclusions

Summary

Introduction

Obesity is a growing public health problem and an ever-increasing global pandemic with individual and general consequences. Whereas the solution to the obesity “problem” appears as easy as increasing energy expenditure and reducing energy intake, failure of attempts to change individual lifestyle within an obesogenic environment indicates that understanding the complex interactions between genetics, physiology, environmental and social behavior are essential in the control of human energy balance. This review will focus on the effects of circadian rhythm disruption on the regulation of energy balance components (food intake and energy expenditure). It is a narrative review not set to systematically include the entire body of published literature but only the pivotal studies that may provide a broad perspective on the topic

The Regulation of Energy Balance

Circadian Rhythm and Energy Balance

Findings

Conclusions