Abstract

Introduction: Various studies have demonstrated the effectiveness of vegetarian diets in reducing obesity and its associated health risks. However, available evidence in the Latin American context is limited. Therefore, this study aims to compare the effects of a low-fat ovo-lacto-vegetarian diet and an omnivorous diet on nutritional status, waist circumference, and body composition in overweight adult women. Methods: A quasi-experimental study was conducted over 30 days with 26 women aged 20 to 55 years. Participants were randomly assigned to two groups (13 participants each): one following a low-fat omnivorous diet and the other a low-fat ovo-lacto-vegetarian diet. Body weight, Body Mass Index (BMI), waist circumference, Fat Mass (FM), and Fat-Free Mass (FFM) were assessed before and after the intervention. Results: Both diets significantly reduced body weight, BMI, and waist circumference. Although no significant differences were observed in FM and FFM between groups, the vegetarian group showed a greater reduction in waist circumference. Conclusion: Low-fat diets, regardless of their source (plant-based or omnivorous), when properly guided and followed in the short term, improve anthropometric and cardiovascular risk parameters such as body weight and waist circumference in overweight adult women. © 2025 Sociedad Chilena de Nutrición, Bromatología y Toxicología.