Circadian rhythms, food timing and obesity

Abstract

It is known that our physiology changes throughout the day and that several physiological hormones display circadian rhythmicity. The alteration of this normal pattern is called chronodisruption (CD). In recent years, it has been demonstrated that CD is related to obesity. Although several factors may be causing CD, one important aspect to consider is the failure in our internal clock. Indeed, studies performed in mutant animals have demonstrated that mutations in clock genes are related to obesity. In human subjects, mutations are rare (<1 % of the population). Nevertheless, it is rather common to have genetic variations in one SNP, which underlie differences in our vulnerability to disease. Several SNP in clock genes are related to obesity and weight loss. Taking into account that genetics is behind CD, as has already been demonstrated in twins’ models, the question is: Are we predestinated? We will see along these lines that nutrigenetics and epigenetics answer: ‘No, we are not predestinated’. Through nutrigenetics we know that our behaviours may interact with our genes and may decrease the deleterious effect of one specific risk variant. From epigenetics the message is even more positive: it is demonstrated that by changing our behaviours we can change our genome. Herein, we propose modifying ‘what, how, and when we eat’ as an effective tool to decrease our genetic risk, and as a consequence to diminish CD and decrease obesity. This is a novel and very promising area in obesity prevention and treatment.

The effect of shift work on eating habits: a systematic review

“…Studies of workers and the general population have shown that changes in the pattern of meals are an independent risk factor for weight gain (56), glucose intolerance, insulin resistance, dyslipidemia and obesity (57)(58)(59). Skipping breakfast is associated with excess weight and changes in metabolic markers, regardless of total caloric intake (60)(61)(62). In addition, the increased consumption of food and calories during the night has also been associated with metabolic changes and weight gain (62)(63)(64)(65).…”

PTPRS and PER3 methylation levels are associated with childhood obesity: results from a genome‐wide methylation analysis

“…In the present study, we have analysed PER3 methylation, and we have confirmed the negative correlation between this gene and childhood obesity that was observed in the microarray. Interestingly, several studies described the role of the methylation of a related gene ( PER2 ) in obesity and metabolic syndrome .…”

“…In the present study, we have analysed PER3 methylation, and we have confirmed the negative correlation between this gene and childhood obesity that was observed in the microarray. Interestingly, several studies described the role of the methylation of a related gene (PER2) in obesity and metabolic syndrome (22,24). The negative association between BMI z-score and methylation levels of PTPRS and PER3 indicates that children with high methylation levels presented lower degree of obesity.…”

Epigenetic Regulation of Circadian Rhythm and Its Possible Role in Diabetes Mellitus

“…CCGs adjust the internal environment so that the organism can function optimally. Hierarchically, there are mechanisms that synchronize CCGs with the outer environment (for example timing of food intake) [20][21][22].…”