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.
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.
• 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.
King Saud University
Lead sponsor
King Saud Medical City
Collaborator