Chrono-ALIGN: A Chronotype-Based Chrono-Nutrition Intervention in Post-Bariatric Patients

NCT07324044 | Not Yet Recruiting DMC

• 1 other identifier: Chrono-ALIGN
• Study Type: interventional
• Target: 246
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized controlled trial will evaluate the impact of chrono-nutrition, a dietary approach that aligns meal timing with the body's circadian rhythms, on weight change, metabolic outcomes, appetite, and gut microbiota in post-bariatric surgery patients. A total of 246 adults who underwent sleeve gastrectomy at least six months earlier will be enrolled at King Saud Medical City. Participants will be randomized to receive either standard post-bariatric nutritional care or personalized chrono-nutrition based on individual chronotype. Outcomes include weight change, metabolic biomarkers, dietary behaviors, sleep patterns, and gut microbiota composition. The study aims to determine whether integrating chrono-nutrition into post-bariatric follow-up can enhance metabolic health and improve long-term health.

Conditions

Obesity (Disorder); Morbid Obesity; Bariatric Sleeve Gastrectomy; Meal Time; Chronotype; Circadian Rhythm

Keywords

chrononutrition; Bariatric Surgery; Gastric Sleeve; Gut Microbiota; Appetite; Meal Timing

Outcome Measures

Primary Outcomes (1)

• Change in weight maintenance and insulin sensitivity

  Evaluate the effect of personalized chrono-nutrition interventions (early time-restricted eating and chronotype-based nutrition) on weight loss maintenance and insulin sensitivity in post-bariatric patients.

  Baseline, 3 months, 6 months, and 12 months

Secondary Outcomes (4)

• Change in gut microbiota diversity and composition

  Baseline, 6, 12 months

• Change in circadian gene expression and epigenetic markers

  Baseline, 3, 6, 12 months

• Change in gut-derived hormones

  Baseline and 12 months

• Change in inflammatory markers and lipid profile

  Baseline, 6, 12 months

Study Arms (3)

Standard Post-Bariatric Care

ACTIVE COMPARATOR

Participants receive routine post-bariatric nutritional care with no prescribed meal-timing window. Dietitians provide standard guidance on protein adequacy (\~60-80 g/day unless otherwise indicated), hydration, and routine micronutrient supplementation per clinic practice. Follow-ups occur at 3, 6, and 12 months; outcomes include body weight, metabolic markers, appetite-related hormones, questionnaires, wearables, and stool samples. This arm controls for the effects of usual care and non-timing dietary counseling.

Behavioral: Standard Post-Bariatric Care (Control)

Early Time-Restricted Eating (eTRE)

EXPERIMENTAL

Participants consume all caloric intake within a fixed daytime 10-hour window (08:00-18:00) on ≥6 days/week. Water/unsweetened tea/black coffee are allowed outside the window. Diet composition follows bariatric guidelines (protein \~60-80 g/day, hydration, routine micronutrients). Dietitians provide structured meal-timing plans and problem-solving support; timing logs and wearables document adherence. Assessments at 3, 6, and 12 months mirror the control arm.

Behavioral: Early Time-Restricted Eating (eTRE)

Chronotype-Based Chrono-Nutrition (CB-CN)

EXPERIMENTAL

Meal timing is personalized to chronotype (morning/intermediate/evening) determined with the Munich Chronotype Questionnaire (MCTQ). Plans target an earlier first meal and completion of the last meal ≥3-4 h before habitual bedtime, with an eating window of \~10 h/day on ≥6 days/week, adjusted to chronotype using stepwise phase-advance strategies where needed. Diet composition follows bariatric guidelines (protein, hydration, micronutrients). Timing logs and wearables track adherence; visits at 3, 6, and 12 months.

Behavioral: Chronotype-Based Chrono-Nutrition (CB-CN)

Interventions

Early Time-Restricted Eating (eTRE) BEHAVIORAL

Participants consume all caloric intake within a fixed daytime 10-hour window (08:00-18:00) on ≥6 days/week. Water/unsweetened tea/black coffee are allowed outside the window. Diet composition follows bariatric guidelines (protein \~60-80 g/day, hydration, routine micronutrients). Dietitians provide structured meal-timing plans and problem-solving support; timing logs and wearables document adherence. Assessments at 3, 6, and 12 months mirror the control arm.

Early Time-Restricted Eating (eTRE)

Chronotype-Based Chrono-Nutrition (CB-CN) BEHAVIORAL

Meal timing is personalized to chronotype (morning/intermediate/evening) determined with the Munich Chronotype Questionnaire (MCTQ). Plans target an earlier first meal and completion of the last meal ≥3-4 h before habitual bedtime, with an eating window of \~10 h/day on ≥6 days/week, adjusted to chronotype using stepwise phase-advance strategies where needed. Diet composition follows bariatric guidelines (protein, hydration, micronutrients). Timing logs and wearables track adherence; visits at 3, 6, and 12 months.

Chronotype-Based Chrono-Nutrition (CB-CN)

Standard Post-Bariatric Care (Control) BEHAVIORAL

Participants receive routine post-bariatric nutritional care with no prescribed meal-timing window. Dietitians provide standard guidance on protein adequacy (\~60-80 g/day unless otherwise indicated), hydration, and routine micronutrient supplementation per clinic practice. Follow-ups occur at 3, 6, and 12 months; outcomes include body weight, metabolic markers, appetite-related hormones, questionnaires, wearables, and stool samples. This arm controls for the effects of usual care and non-timing dietary counseling.

Standard Post-Bariatric Care

Eligibility Criteria

• Age: 18 Years - 50 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Adults aged 18-50 years who underwent Sleeve Gastrectomy (SG) 6 Months prior to enrollment.
• Have achieved ≥50% of excess weight loss post-surgery (to ensure initial success).
• Current BMI between 25-40 kg/m².
• No major postoperative complications and cleared for a regular diet by their healthcare provider.
• Participants must be able to align their eating schedule within a daytime window (morning to evening), ensuring that the first meal is consumed in the early part of the day and the last meal is completed before late evening, in accordance with chrono-nutrition guidelines.

You may not qualify if:

• Pregnancy or planned pregnancy during the study period, and post menopaused females
• Current diagnosis of severe psychiatric illness that may interfere with adherence (e.g., untreated major depression, psychosis, severe eating disorders).
• Active malignancy or serious chronic disease unrelated to obesity that may confound outcomes (e.g., advanced renal failure, uncontrolled liver disease).
• Use of medications known to significantly alter circadian rhythm or metabolism (e.g., corticosteroids, melatonin therapy) within the last 3 months.
• Inability to comply with study requirements (dietary interventions, sample collection, or follow-up visits).Participants who have previously undergone revision bariatric surgery.
• Individuals following intermittent fasting regimens prior to the study.

Sponsors & Collaborators

• King Saud University: lead
• King Saud Medical City: collaborator

Study Sites (1)

King Saud Medical City

Riyadh, Saudi Arabia

Location

MeSH Terms

Conditions

Obesity; Obesity, Morbid

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Amani A Al-Farraj, Master

  King Saud University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Amani A Al-farraj, Master

CONTACT

+966508947215; Alfarrajamani@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Masking Details: Due to the behavioral nature of the dietary interventions, participants and care providers cannot be blinded. However, outcome assessors, including laboratory personnel and data analysts, will remain blinded to group allocation to minimize detection and analysis bias.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Ms.

Model Details: This study uses a parallel assignment design with three arms. Participants will be randomized in a 1:1:1 ratio to (1) standard post-bariatric nutritional care without specific meal timing (Control), (2) early time-restricted eating (eTRE); or (3) chronotype-based chrono-nutrition (CB-CN; meal timing tailored to individual chronotype using the Munich Chronotype Questionnaire). Each intervention follows bariatric guidelines emphasizing protein adequacy, hydration, and micronutrient supplementation. The model is designed to evaluate whether aligning meal timing with chronotype improves weight loss maintenance, metabolic health, gut microbiota composition, epigenetic regulation, and psychological outcomes at 12 months

Study Record Dates

• First Submitted: December 23, 2025
• First Posted: January 7, 2026
• Study Start: January 1, 2026
• Primary Completion (Estimated): December 1, 2027
• Study Completion (Estimated): December 1, 2028
• Last Updated: January 7, 2026

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

SA (1)