Metabolic Impact on the Mitochondria-gut Microbiota Axis of Failure to Follow Restrictive Dietary Interventions in Subjects Living With Obesity

The study consists of an open-label randomized controlled clinical trial. The selected subjects will be men or women over 18 years of age with a body mass index (BMI) greater than or equal to 30 kg/m2, who meet the selection criteria, the subjects who will be randomly assigned to one of 3 dietary intervention groups. The study consisted of a dietary intervention with a duration of 8 weeks and a follow-up of 24 weeks after dietary intervention. The intervention groups will be as follows: 1. Calorie-restricted diet: Dietary recommendations will be given restricting 30% in energy (kcal) according to their usual diet with normal macronutrient distribution (20-30% protein, 50-60% carbohydrates, 20-30% fats). 2. Intermittent fasting diet: Dietary recommendations will be given according to the energy expenditure determined by indirect calorimetry with normal macronutrient distribution. Intermittent fasting will be used with a time-restricted model of 16:8. For 16 hours, they will not be able to eat or drink calories. In the other 8 hours, they need to adhere to the energy-restricted diet. 3. Ketogenic diet: Recommendation will be given according to the energy expenditure determined by indirect calorimetry, with the following distribution of macronutrients: 20-25% protein, 5-10% carbohydrates, 70-80% fat. Participants with calorie-restriction, intermittent fasting, or ketogenic diet dietary intervention will be provided with a food menu guide for fifteen days. After 8 weeks of the assigned intervention, patients will be provided with general dietary recommendations and will be invited to three more follow-up visits at 8, 16 and 24 weeks post-intervention. In addition, all participants will be provided with general recommendations for a physical activity plan for people living with obesity. To evaluate adherence to treatment, participants will be asked to fill out 2 logbooks every two weeks (1 during the week and 1 for the weekend) in which they must record the type, amount and place where they consumed the food at each feeding time. They will also be called once a week for a 24-hour reminder. Participants on the ketogenic diet will be given test strips to measure ketones in urine.