study of the effects of time-restricted feeding on the immune function of individuals with obesity

Conditions: Obesity and Obesity-related Medical Conditions

Summary: 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


Eligibility criteria:
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.