Time-restricted Eating in Morning Chronotype

Study Overview
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Brief Summary
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Overweight and obesity are highly prevalent conditions worldwide, despite active research of new interventions over decades. Current interventions include medications or bariatric surgery, but these approaches cannot be used in all patients and require clear indications and a close multidisciplinary management. Therefore most patients and physicians rely on lifestyle interventions, focusing on a balanced diet and physical exercise. Recent studies have uncovered that energy metabolism is also regulated by circadian rhythms, which depend on spontaneous diurnal oscillations of the central clock, retinal sensing of ambient light, and daily feeding-fasting cycles. The chronotype has an influence on behavioral patterns, where some people describe that they are more alert in the morning or in the evening: The morning or evening chronotypes, respectively. However, in modern societies, many people are exposed to external cues in misalignment with their circadians clocks. The mismatch between the individual chronotype and the social/work life can lead to metabolic disorders. Time-restricted eating (TRE), i.e. energy intake limited to certain windows of time without restricting calories, is an appealing approach because it proposes to realign the circadian clocks with external cues provided by the timing of food intake, thus leading to better metabolic outcomes. The investigators speculate that the TRE intervention needs to be personalized to reach efficacy in a broader population. To tailor the TRE intervention to each individual and harmonize their eating patterns in accordance to their chronotype, the investigators plan to test early TRE vs. late TRE vs. active control in overweight and obese individuals with morning chronotype.

Official Title
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Time-restricted Eating to Improve Body Fat Mass in Overweight and Obese Individuals With Morning Chronotype: A Randomized, Open-label, Multi-arm Trial

Conditions
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Overweight and Obesity

Intervention / Treatment
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* Behavioral: Early time-restricted eating
* Behavioral: Late time-restricted eating
* Behavioral: Active control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical criteria Men and premenopausal women Age 25-50 years BMI 25-34 kg/m2 Stable weight (maximum ± 2 kg of usual body weight) over the previous 3 months Stable body fat mass (maximum ± 1 kg of body fat mass) during the run-in phase Eating window ≥ 12 hours during the run-in phase Morning chronotype Work-related criteria Daytime work at least 3 days per week over the previous 1 month and planned during the study Study-related criteria Able to give informed consent and follow the study procedures for the entire duration Confident use of a smartphone and able to take regular pictures of food/drinks Exclusion Criteria: Clinical criteria Pregnant and breastfeeding women, plans for maternity during the study On a diet, intermittent fasting, in a weight management program over the previous 3 months or planned during the study Eating disorder(s) or prior bariatric surgery Diabetes with hypoglycemic drug(s) Major illness/fever over the previous 1 month Active major cardiovascular, respiratory, liver, gastrointestinal, renal, neurological or endocrine disorders Coagulation disorder, on anticoagulant drug, skin disorder affecting wound healing Active cancer and/or oncologic treatment over the previous 12 months Major sleep disorder (including untreated sleep apnea syndrome), major mental illness Consumption of > 7 standard units of alcohol per week for women and > 14 standard units of alcohol per week for men Work and time-related criteria Shift work, such as evening shifts or night shifts, over the previous 1 month or planned during the study Travel/trip to a different time zone (≥ 2-hour time difference) over the previous 1 month or planned during the study Study-related criteria and other interventions Enrolled in another interventional clinical trial (medication, medical device) over the previous 1 month and planned during the study Regular medications over the previous 1 month that could affect the study endpoints (e.g. centrally acting, medications affecting gut absorption, transit or weight, hypoglycemic drug, hormonal treatment...)

Ages Eligible for Study
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Minimum Age: 25 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Early time-restricted eating<br>Duration: 12 weeks | Behavioral: Early time-restricted eating<br>* Participants will be advised to eat only during a selected window of 8 hours over the 24-hour cycle, i.e. from 6am to 2pm, with a 1-hour allowance according to their daily routine<br>* Other names: Early TRE;|
| Experimental: Late time-restricted eating<br>Duration: 12 weeks | Behavioral: Late time-restricted eating<br>* Participants will be advised to eat only during a selected window of 8 hours over the 24-hour cycle, i.e. from noon to 8pm, with a 1-hour allowance according to their daily routine<br>* Other names: Late TRE;|
| Active Comparator: Active control<br>Duration: 12 weeks | Behavioral: Active control<br>* Participants will be advised to eat a minimum of 3 meals over the 24-hour cycle, i.e. breakfast from 6am to 9am, lunch from 11am to 2pm, dinner from 6pm to 10pm. Snacks will be allowed between meals<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in body fat mass | As measured by dual-energy x-rax absorptiometry (DXA) | From randomization visit to close-out visit (12 weeks) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in physical activity | As measured by actigraphy | From randomization visit to close-out visit (12 weeks) | 
| Change in sleep/wake cycles | As measured by actigraphy | From randomization visit to close-out visit (12 weeks) | 
| Change in ambient light | As measured by actigraphy | From randomization visit to close-out visit (12 weeks) | 
| Change in sleep quality | As measured by the Pittsburgh Sleep Quality Index (scale 0-21, 0 indicating no sleeping difficulty, 21 indicating severe sleeping difficulties) | From randomization visit to close-out visit (12 weeks) | 
| Change in eating duration | Duration from the first to last caloric intake over 24-hour cycle | From randomization visit to close-out visit (12 weeks) | 
| Change in calorie intake over the 24-hour cycle | Assessed by a 24-hour food recall | From randomization visit to close-out visit (12 weeks) | 
| Change in weight | Body weight (kg) | From randomization visit to close-out visit (12 weeks) | 
| Change in waist circumference | Waist circumference (cm) assessed with a measuring tape | From randomization visit to close-out visit (12 weeks) | 
| Change in hip circumference | Hip circumference (cm) assessed with a measuring tape | From randomization visit to close-out visit (12 weeks) | 
| Change in systolic and diastolic blood pressure | As measured with an arm cuff in the sitting position | From randomization visit to close-out visit (12 weeks) | 
| Change in fasting glucose | As measured in clinical chemistry | From randomization visit to close-out visit (12 weeks) | 
| Change in lipid profile (concentration of total cholesterol, LDL cholesterol, triglycerides, HDL cholesterol) | As measured by clinical chemistry | From randomization visit to close-out visit (12 weeks) | 
| Change in body fat mass | As measured by bioelectrical impedance analysis (BIA) | From randomization visit to close-out visit (12 weeks) | 
| Change in lean body mass | As measured by dual-energy x-rax absorptiometry (DXA) | From randomization visit to close-out visit (12 weeks) | 
| Change in fat-free mass | As measured by bioelectrical impedance analysis (BIA) | From randomization visit to close-out visit (12 weeks) | 
| Change in resting energy expenditure | As measured by indirect calorimetry | From randomization visit to close-out visit (12 weeks) | 
| Change in glucose excursion | As measured by continuous glucose monitoring | From randomization visit to close-out visit (12 weeks) | 
| Incidence of adverse events in response to the randomized intervention | Adverse events graded after the Common Terminology Criteria for Adverse Events version 5.0 | From randomization visit to close-out visit (12 weeks) |