The effect of intermittent fasting diets on body weight and composition

Abstract

Background & aims: This study was carried out to determine and compare the effects on anthropometric measurements of the Mediterranean Diet (MD) with daily energy restriction and four different intermittent fasting diets (IFD), which were created as an alternative to MD and gained popularity.

Methods: 360 people aged 18-65 years, with body mass index (BMI) between 27 and 35 kg/m² participated to the study. Demographic information, anthropometric measurements, physical activity and food consumption records were obtained by the researcher through weekly face-to-face interviews. The study lasted for 13 weeks, the first of which was a trial. Statistical significance level was accepted as 0.05. Participants were randomly assigned to 5 equal groups: Mediterranean Diet (MD), Week on Week off (WOWO), 6-Hour Time-Restricted Eating (TRE-6), 8-Hour Time-Restricted Eating (TRE-8), Alternative Day Diet (ADD). Of the 360 people who participated in the study, 32 (2 TRE-6, 7 WOWO, 1 MD, 16 ADD, 6 TRE-8) dropped out after the trial week.

Results: It was determined that throughout the study, body weights, BMI, arm circumferences and waist circumferences in all groups decreased significantly. However, trends in changes in body weights and BMIs did not differ between groups. While the energy, carbohydrate, protein and fat intakes of the participants did not change significantly during the study, fiber consumption increased considerably in the MD and WOWO groups.

Conclusions: It was observed that IFD were not superior to MD in terms of anthropometric measurements. The health effects and long-term consequences are not clear for IFD, unlike MD. For these reasons, it is thought that the most effective nutritional therapy that can be preferred for healthy weight loss is the energy-restricted MD model.

Keywords: Alternate day diet; Intermittent fasting diet; Weight loss.