Efficacy of Intermittent Fasting Versus Continuous Caloric Restriction in the Treatment of Significant Weight Regain After Bariatric Surgery

Summary

Intermittent fasting has gained relevance in recent years because it allows for significant weight loss with improvement in cardiovascular risk factors similar to calorie-restricted diets without people having to track calories every day, or prohibiting people from eating certain food groups. However, there is no data about its usefulness in patients with weight gain after bariatric surgery, or its long-term effects(9).

Research question: In patients with weight gain, being followed up in the obesity clinic, is intermittent fasting for 12 weeks, compared to calorie restriction, effective in terms of weight reduction?

H0: Change in weight from baseline to 12 weeks less than 5% H1: Change in weight from baseline to 12 weeks greater than or equal to 5%

Patients meeting the inclusion criteria will be identified. Once identified, they will be asked to participate in the study and, if they accept, they will be asked to complete and sign the informed consent form. The study will consist of three phases: a selection phase, an adaptation phase (1 to 2 weeks), a weight loss phase (12 weeks) and a maintenance phase (12 weeks).

At the first visit, patients will be randomized to two types of nutritional interventions: intermittent fasting or caloric restriction. During the weight loss phase, biweekly follow-up will be performed to ensure adherence to the assigned dietary intervention. At the end of the 12 weeks, patients can decide whether to continue the assigned dietary intervention or move to a maintenance plan. Anthropometric measurements and body composition will be measured at baseline, 12 and 24 weeks.

Conditions

• Obesity Prevention
• Bariatric Surgery Complications
• Intermittent Fasting

Interventions

OTHER

Intermittent Fasting

Participants in the alternate-day fasting group will receive biweekly telecounseling to ensure adherence to the prescribed dietary plan and to monitor for potential adverse events. During the 12-week weight loss phase, patients are instructed to restrict calories to 75% of usual intake 2 days per week. A daily intake of at least 2 liters of low-energy beverages (water, caffeine- and sugar-free beverages) is generally recommended on fasting days. Usual physical activity is encourage

OTHER

Continuous calorie restriction

Participants in the continuous calorie restriction group will receive biweekly nutritional counseling via Telecoaching to ensure adherence to the prescribed dietary plan. Based on weekly caloric intake obtained from the 7-day log, a model menu will be prescribed with a 25% daily calorie restriction divided among 3 meals every day consisting of macronutrient intake, with 20% of energy as fat, 40 to 50% as carbohydrate, and 20 to 30% as protein. They will be instructed to continue their usual physical activity.

Sponsors & Collaborators

• Pontificia Universidad Javeriana

  collaborator OTHER

• Hospital Universitario San Ignacio

  lead OTHER

Principal Investigators

• Diana C Henao, Endocrinologyst · Hospital Universitario San Ignacio

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Max Age

69 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2023-12-19

Primary Completion

2025-01-31

Completion

2025-06-30

Countries

• Colombia

Study Locations