Study of the Effects of Time-Restricted Feeding on the Immune Function of Individuals With Obesity (OBESIMM)

Exploring the Effects of Time-Restricted Feeding on the Immune Function of Obese Individuals: A Multi-Omic Approach

The goal of this randomized trial is to: 1) investigate the immunological landscape of patients with obesity and conduct an in-depth functional characterization of their immune system; and 2) precisely define the effects of time-restricted feeding (TRF) on immune function in patients with obesity; 3) define the immunomodulatory properties of white adipocytes in response to TRF, and 4) uncover the underlying mechanisms by which TRF modulates the immune system patients with obesity through a multi-omics approach.

The main questions it aims to answer are: i) what is the underlying cause of impaired immunocompetence in patients with obesity? ii) how nutritional interventions improve the immune function of patients with obesity? Patients with obesity following TRF (8 h eating window ranging from 6-8 am to 14-16 pm) will be compared to patients with obesity without TRF control schedule (14h eating window ranging from 6-8 am to 8-10 pm). The dietary intervention will begin 10 weeks before the scheduled date for bariatric surgery in patients with obesity. In addition to patients with obesity, the present study aims to recruit a group of a reference healthy group (BMI between18.5-24.9 kg/m²) that will not receive any nutritional intervention.

The following endpoints will be collected: Body weight and composition using Bioelectrical Impedance Analysis, resting energy expenditure (REE) using indirect calorimetry, blood glucose levels using a continuous glucose monitoring (CGM) device, metabolic parameters (fasting blood glucose levels, C-peptide, HbA1c, insulin, HOMA-IR, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, hepatic enzymes), and cytokine profile.

Blood, stool, and white adipose tissue (WAT) samples will be collected to establish metagenomic, transcriptomic, cytomic and metabolomic analyses

Study Overview

• Status: Recruiting
• Conditions: Obesity and Obesity-related Medical Conditions
• Intervention / Treatment: Other: Time-restrictred feeding; Other: Non-time restricted feeding

• Study Type: Interventional
• Enrollment (Estimated): 45
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Josep A. Villena Delgado; Phone Number: + 34 937372429; Email: josep.villena@vhir.org

Study Locations

• Spain
  • Barcelona, Spain, 08035
    • Recruiting
    • Vall Hebron Barcelona Hospital Campus
    • Principal Investigator: ANDREEA CIUDIN
    • Contact: Josep A. Villena Delgado; Phone Number: + 34 937372429; Email: josep.villena@vhir.org
    • Principal Investigator: Ramón Vilallonga

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Patients with obesity

• Women
• Age 18-64 years
• Body mass Index between 40-50 kg/m²
• Scheduled bariatric surgery 10-12 weeks after the nutritional intervention
• Self-reported eating pattern window of more than 14h
• Three meal eating pattern
• Stable body weight (less than 10% of current body weight during the last 3 months)
• Patients who have a favorable decision from the multidisciplinary team meetings after multidisciplinary nutritional follow-up of at least 6 months and history of failure with non-surgical weight loss methods
• Social security affiliation
• Written consent
• Good understanding of the Catalan or Spanish languages

Exclusion Criteria:

• Diabetes type I or II
• Major cardiovascular disease
• Pregnancy
• Medication that could affect the study outcomes (i.e. anti-inflammatory drugs, antibiotics, immunosuppressors)
• Use products intended for weight loss
• Night work shift
• Past record of malignant tumors
• Serious liver dysfunction or chronic kidney disease
• Eating disorders
• Chronic viral disease (Hepatitis B or C, HIV) or inflammatory systemic diseases (i.e. Crohn's disease, rheumatoid arthritis)
• Serious cardiovascular or cerebrovascular disease within 6 months before randomization
• Severe gastrointestinal diseases or gastrointestinal surgery in the 12 months before randomization
• Under guardianship, curatorship, deprived of liberty
• Unable or unwilling to sign the informed consent form.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Time-restricted feeding; Women with grade 3 obesity (BMI 40-50 kg/m²) who are scheduled for bariatric surgery and follow a time-restricted feeding (TRF) pattern consisting of an 8 h eating window (from 6-8 am to 14-16 pm) followed by a 16 h fasting period.	Other: Time-restrictred feeding; Time-restricted feeding pattern consisting of an 8 h eating window (from 6-8 am to 14-16pm) followed by a 16 h fasting period.
Experimental: Non-Time restricted feeding; Women with grade 3 obesity (BMI 40-50 kg/m²) who are scheduled for bariatric surgery and follow a 14h eating window (from 6-8 am to 8-10pm), followed by a 10 h fasting period.	Other: Non-time restricted feeding; 14h eating window (from 6-8 am to 8-10 pm), followed by a 10 h fasting period.
No Intervention: Control; Women with a healthy body weight without any dietary intervention.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inflammatory cytokine IL-1β	The mean difference in inflammatory cytokine IL-1β in patients with obesity after 10 weeks under TRF versus patients withobesity without TRF.	10 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percent of weight change from baseline		Baseline, 10 weeks
Change in body composition (lean and fat mass) from baseline		Baseline, 10 weeks
Change in resting energy expenditure from baseline		Baseline, 10 weeks
Change in fasting blood glucose levels from baseline		Baseline, 10 weeks
Change in fasting C-peptide from baseline		Baseline, 10 weeks
Change in HbA1c from baseline		Baseline, 10 weeks
Change in fasting insulin levels from baseline		Baseline, 10 weeks
Change in HOMA-IR from baseline		Baseline, 10 weeks
Change in lipid profile from baseline	Baseline, 10 weeks	Baseline, 10 weeks
Change in hepatic enzymes from baseline		Baseline, 10 weeks
Change in cytokine profile from baseline		Baseline, 10 weeks
Changes in blood metabolome		Baseline, 10 weeks
Changes in gut microbiome		Baseline, 10 weeks
Changes in adipose tissue metabolome		Baseline, 10 weeks
Changes in gene expression profile		Baseline, 10 weeks
Changes in blood immune cell populations		Baseline, 10 weeks
Changes in adipose tissue immune cell populations		Baseline, 10 weeks

Collaborators and Investigators

• Sponsor: Hospital Universitari Vall d'Hebron Research Institute

Study record dates

Study Major Dates

• Study Start (Actual): March 21, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: February 27, 2025
• First Submitted That Met QC Criteria: February 27, 2025
• First Posted (Actual): March 5, 2025

Study Record Updates

• Last Update Posted (Actual): June 8, 2025
• Last Update Submitted That Met QC Criteria: June 4, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Overweight; Obesity
• Other Study ID Numbers: PR(AG)68/2023

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data (IPD) that underlie results in publication could be shared. IPD detailed in theprotocol of a planned metaanalysis could be shared.
• IPD Sharing Time Frame: Two years after the last publication.
• IPD Sharing Access Criteria: Data sharing must be accepted by the sponsor and the PI based on a scientific project and scientific involvement of the PI team. Collaboration will be fostered. The founder could be involved in the decision. Teams wishing obtain IPD must meet the sponsor and IP team to present scientifics (and commercial) purpose, IPD needed, format of data transmission, and timeframe. Technical feasibility and financial support will be discussed before mandatory contractualization. Processing of shared data must comply with EuropeanGeneral Data Protection Regulation (GDPR).
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

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