Time-restricted Eating in Morning Chronotype

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

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.

Study Overview

• Status: Completed
• Conditions: Overweight and Obesity
• Intervention / Treatment: Behavioral: Early time-restricted eating; Behavioral: Late time-restricted eating; Behavioral: Active control

• Study Type: Interventional
• Enrollment (Actual): 92
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Geneva, Switzerland, 1211
    • Geneva University Hospitals

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 25 years to 50 years (Adult)
• Accepts Healthy Volunteers: No

Description

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...)

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Early time-restricted eating; Duration: 12 weeks	Behavioral: Early time-restricted eating; 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; Other Names: Early TRE
Experimental: Late time-restricted eating; Duration: 12 weeks	Behavioral: Late time-restricted eating; 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; Other Names: Late TRE
Active Comparator: Active control; Duration: 12 weeks	Behavioral: Active control; 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

What is the study measuring?

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)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in in vitro circadian parameters (amplitude and magnitude)	As measured in cultured skin fibroblasts (in a subset of the study population)	From randomization visit to close-out visit (12 weeks)
Change in metabolomic parameters	As measured by high-throughput mass spectrometry metabolomics	From randomization visit to close-out visit (12 weeks)
Change in lipid metabolism	As measured by high-throughput mass spectrometry lipidomics	From randomization visit to close-out visit (12 weeks)
Change in blood hormonal profile	Cortisol, insulin, thyroid-stimulating hormone	From randomization visit to close-out visit (12 weeks)

Collaborators and Investigators

• Sponsor: Tinh-Hai Collet, MD
• Investigators: Principal Investigator: Tinh-Hai Collet, MD, Geneva University Hospitals, Geneva

Study record dates

Study Major Dates

• Study Start (Actual): January 4, 2021
• Primary Completion (Actual): July 15, 2024
• Study Completion (Actual): October 22, 2024

Study Registration Dates

• First Submitted: October 28, 2020
• First Submitted That Met QC Criteria: November 4, 2020
• First Posted (Actual): November 5, 2020

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 11, 2024
• Last Verified: December 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Overweight
• Other Study ID Numbers: 2020-01439

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No