Chocolate and Menopause Time
Condition: Menopause
Study type: Interventional

Summary: 
      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.
    

Detailed description: 
      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:

        1. Metabolism: resting energy expenditure, corrected resting energy respiratory quotient
           (RQ)

        2. Glucose metabolism

        3. Total weight loss

        4. Food intake, total energy intake, and type of food

        5. Microflora (feces)

        6. Mood

        7. 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).
    

Intervention name(s): Morning Chocolate Timing; Evening Chocolate Timing; No Chocolate Timing
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): During two consecutive weeks volunteers will eat chocolate within 1 hour of their habitual wake-time (100g).; During two consecutive weeks volunteers will eat chocolate within 1 hours of habitual bedtime (100g).; During two consecutive weeks volunteers will not eat chocolate.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Chocolate; Timing; Menopause; Calorimetry