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

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.