Recent studies suggest that not only what the people eat, but also when the people eat may have a significant role in obesity treatment and in the regulation of the circadian system. Thus, the hypothesis of this study is eating a relatively big amount of chocolate at the wrong time, bedtime may affect:~Metabolism: resting energy expenditure, corrected resting energy respiratory quotient (RQ)~Glucose metabolism~Total weight loss~Food intake, total energy intake, and type of food~Microflora (feces)~Mood~Disrupt our circadian system 7a) Changes in Temperature, Actimetry, and Position 7b) Electrocardiogram (ECG) 7c) Melatonin (two points) cortisol rhythm (three points) While having this same amount of chocolate in the morning (wake up condition) may synchronize it.~Other related factors may be also affected such as total body weight and body fat, dietary habits (total energy intake and macronutrient distribution), the timing of food intake and of sleep, daily rhythms of TAP, microflora composition and postprandial glycemia.~19 women (postmenopausal) following the habitual dietary habits of participants (ad libitum) will have 30% of the habitual total daily calories in chocolate of participants (Nestle, chocolate with milk) during two consecutive weeks each under three conditions: eating chocolate within 1 hour of habitual wake-time, eating chocolate within 1 hours of habitual bedtime, or eating no chocolate. No other chocolate (i.e., none at all in control and in the washout weeks).~The protocol will be a randomized, cross-over design, with a 1-week washout between each condition.~During the 14 days in each condition, the participants will record sleep and activity schedules by dairy, food intake and food timing by phone application, daily rhythms of wrist temperature, activity and position (TAP).
The purpose of this investigation is to test the hypothesis that in humans, eating a relatively big amount of chocolate at the wrong time (bedtime) may disrupt our circadian system (change the circadian phase), while taking this same amount of chocolate in the morning (wake up condition) may synchronize it. Other related factors may be also affected such as total body weight and body fat, dietary habits (total energy intake and macronutrient distribution), the timing of food intake and of sleep, daily rhythms of TAP, microflora composition and postprandial glycemia.