SUN-720 - Comparative Effects of Intermittent Fasting and Caloric Restriction on Metabolic Syndrome: A Randomized Clinical Trial in Nicaragua.

Background;
Metabolic syndrome is a significant public health concern associated with obesity, insulin resistance, and increased cardiometabolic risk. Although daily caloric restriction is commonly recommended for weight management, long-term adherence is often limited. Intermittent fasting has emerged as an alternative dietary strategy; however, comparative clinical evidence in Latin American populations remains limited.

Objective: To compare the effects of intermittent fasting and daily caloric restriction on body weight, anthropometric measurements, cardiometabolic risk markers, and quality of life in adults with metabolic syndrome.
Methods

A randomized, open-label clinical trial was conducted in adults aged 20–70 years diagnosed with metabolic syndrome at a tertiary teaching hospital in León, Nicaragua (2023–2024). Participants (n=60) were randomly assigned to intermittent fasting (5:2 protocol with 16-hour fasting on two nonconsecutive days per week; n=30) or daily caloric restriction (500–800 kcal/day deficit; n=30) for three months. Outcomes included body weight, anthropometric parameters, cardiometabolic risk markers (lipid profile, fasting glucose, blood pressure, and diabetes risk score), quality of life (FANTASTIC questionnaire), adherence, and adverse effects. Between-group comparisons were performed using Student’s t-test or Mann–Whitney U test for quantitative variables and chi-square tests for categorical variables. Statistical significance was set at p< 0.05.

Results;
Participants were predominantly female (68.3%), aged 30–45 years (43.3%), and residents of León (95%). Intermittent fasting was associated with a statistically significant reduction in body weight compared with baseline (p=0.03). Both interventions resulted in favorable changes in anthropometric and cardiometabolic risk markers; however, differences between the intermittent fasting and caloric restriction groups were not statistically significant. Quality of life was rated as “Good” in 65% of participants, with no significant differences between groups. Adherence rates were comparable between interventions, and no clinically relevant adverse effects were reported.

Conclusion;
Conclusion

Intermittent fasting resulted in significant weight loss and demonstrated effects on cardiometabolic risk markers, quality of life, adherence, and safety similar to those of daily caloric restriction. These findings suggest that intermittent fasting is a feasible and flexible dietary strategy for managing metabolic syndrome. Larger and longer-term studies are warranted to confirm these results and evaluate sustained cardiometabolic outcomes.

Keywords
Intermittent fasting; caloric restriction; metabolic syndrome; cardiometabolic risk; obesity

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