The Effect of Intermittent Fasting on Body Weight, BMI, Waist Circumference, and Fat Mass Percentage in Adults with Overweight or Obesity

Document Type : Research Paper


1 Biomedicine PhD. Centro Multidisciplinario de Investigaciones Tecnológicas, Universidad Nacional de Asunción, Paraguay.

2 Nutritionits. Universidad del Norte – Asunción, Paraguay.


Introduction: Fasting is a state of negative energy balance. Different fasting regimens have been used to achieve weight loss and other health benefits. To evaluate the effects of intermittent fasting on body weight, body mass index (BMI), waist circumference and fat mass percentage in people with overweight or obesity. Methods: This experimental study was conducted on 22 adults of both genders aged 18-60 years, who were overweight or obese. A gradual intermittent fasting intervention was performed for 4 weeks with 10 hours of fasting in the first week and 16 hours of fasting in the last week. Variables such as body weight, BMI, waist circumference, and fat mass percentage were evaluated before and after the intervention in two groups, with and without dietary recommendations (ad libitum). Results: At the end of the intervention, body weight, BMI, and waist circumference were significantly reduced in both groups, except for fat mass percentage. On the contrary, no statistically significant differences were found for all the parameters between groups (p>0.05). Conclusion: According to results, body weight, BMI, and waist circumference decreased significantly in the two groups after four weeks of intermittent fasting.


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