Clock Genes, Chronodisruption, Nutrition and Obesity

Abstract

The existence of biological clocks has been demonstrated in all living beings. Such clocks control the physio-metabolic activities of cells, organs and systems to warrantee efficacy in the process to obtain energy and metabolize nutrients under a homeostatic point of view. These ordered activities are known as circadian rhythms, occurring approximately every 24h, and depend on the activity of groups of neurons (oscillators) negatively interrelated. The oscillatory activity is related to gene expressions that implicate rhythms in the mRNA and protein production. However, alterations in such synchronism is frequently found because of many of human activities are performed in “unexpected” environmental conditions. Thus, light intensity and environmental temperature are normally rather constant; in addition light/darkness cycles are modified by working/leisure times, travels, meals and activities braking the ticking of the biological clocks producing chronodisruption. The aim of this mini review is to give some central information on most common chronodisruption aspects and their relationships with dietary habits and obesity. After a short and concise introduction explaining central aspects of biology clocks and disruptors, the role of some prevalent dietary behaviors (e.g. frequent snaking, late meals and large food consumption) acting at the level of CLOCK genes are described and discussed. This mini review far from to be exhaustive pretends to open discussion on the most accepted information, ending suggesting some future research to understand the role and importance of CLOCK genes and their polymorphisms in obesity.