Association between circadian rhythm with resting metabolic rate in overweight\obese women

Aim: The aim of this study was to investigate the association between circadian rhythm with resting metabolic rate (RMR) in overweight\obese women Methods: This cross-sectional study included 232 obese and overweight women. Morningness-Eveningness Questionnaire (MEQ) was used to assess the level of circadian rhythm. RMR was measured by indirect calorimetry after a 10-12 hour overnight fasting period by a trained nutritionist. We assessed body composition using multi-frequency bioelectrical impedance analyzer (BIA). Results: The percentage of overweight and obese women were 48.7% (113) and 51.3% (119), respectively. The number of participants who were morningness, intermediate and eveningness was 28(12.1%), 135(58.2%) and 69(29.7%) respectively. A significant relationship was found between MEQ and RMR.normal (p=0.011). According to linear regression model non-eveningness participants had 81.92 higher RMR compared to eveningness participants (p=0.027). Conclusion: We found that non-eveningness participants had higher RMR compared to eveningness participants that can have protective effect against obesity, diabetes type2 and other health disorders.