Chronobiology and obesity: The orchestra out of tune

Abstract

Chronobiology is a 'new' area of research that paradoxically began hundreds of years ago. From microarray studies, it is now accepted that, depending on the tissue, 2-25% of total genes expressed have significant changes in their expression levels during the course of the day. Many behavioral, physiological and biochemical variables display circadian rhythms in their expression, acting like a music orchestra directed by a physiological conductor, termed the suprachiasmatic nucleus. When the orchestra is 'out of tune' within our body, we talk about 'chronodisruption', which implies that rhythms can become desynchronized and may have adverse health effects. Jet-lag, shift work, nocturnal light pollution, sleep deprivation or nocturnal eating are all highly associated with obesity. Circadian disruptions in adipose tissue and nutrigenetics aspects are related to this 'out of tune' orchestra that is obesity. © 2010 Future Medicine Ltd.