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

Document Type : Research Paper


1 Biomedicine PhD. Multidisciplinary Center for Technological Investigations - National University of Asuncion, Paraguay.

2 Nutritionist. North University, Asuncion, Paraguay.



Introduction: Fasting is a state of negative energy balance and, as such, different fasting regimens have been used to achieve weight loss as well as other health benefits. To evaluate the effects of intermittent fasting on body weight, body mass index (BMI), waist circumference and percentage of fat mass in people with overweight or obesity. Methods: an experimental study that included 22 adults of both sexes between 18 and 60 years of age who were overweight or obese. A gradual intermittent fasting intervention was performed starting with 10 hours of fasting the first week and ending with 16 hours of fasting in the last week (4 weeks). Variables such as body weight, BMI, waist circumference and percentage of fat mass were evaluated before and after the intervention in two groups, one with dietary recommendations and the other without recommendations (ad libitum). Results: 63.6% were female, the average age was 38.8 years, 68.1% had a university education level, 50% were single, and 36.3% were dedicated to their profession as a job occupation. At the end of the intervention, in both groups, body weight, BMI and waist circumference were significantly reduced, except for % fat mass.  On the contrary, when the results between groups were compared, no statistically significant differences were found for all the parameters (p>0.05) in all cases. Conclusion: Overall in the two groups, body weight, BMI and waist circumference decreased significantly after four weeks of intermittent fasting.


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  • Receive Date: 08 March 2022
  • Revise Date: 26 April 2022
  • Accept Date: 09 May 2022
  • First Publish Date: 09 May 2022