HIGH-FIBER DIET PROMOTES METABOLIC, HORMONAL, AND SATIETY EFFECTS IN OBESE WOMEN ON A SHORT-TERM CALORIC RESTRICTION

Abstract

ABSTRACT Background: Several mechanisms, including excessive hunger, account for patients’ difficulties in maintaining weight loss and dietary changes after caloric restriction. Objective: To evaluate the effect of short-term high-fiber calorie-restricted diet in appetite-regulating hormones, and hunger and satiety sensations in women with obesity. Methds: In a randomized controlled trial study, thirty women with body mass index (BMI) higher than 30 kg/m2, and aged from 20 to 50 years were hospitalized following a calorie-restricted diet (1000 kcal/day) for three days. The experimental group (n=15) received high-fiber diet and the control group (n=15), conventional diet. Body weight, BMI, resting energy expenditure (REE), acylated and total ghrelin, leptin, insulin and glucose, and hunger and satiety sensations were evaluated. Linear regression models with mixed effects (fixed and random effects) helped to assess the variables between the two groups and within the groups. Results: Body weight and BMI decreased in both the experimental and control groups (P<0.001). After the high-fiber diet, postprandial acylated ghrelin (P=0.04), glucose (P<0.001), insulin (P=0.04), and leptin (P=0.03) levels as well as the HOMA-IR index (P=0.01) decreased, whereas satiety improved (P=0.02). Obese women that followed the conventional diet had increased body fat percentage (P=0.04) and lower REE (P=0.02). The two diets did not differ in terms of hunger sensation. Conclusion: A short-term high-fiber diet improves satiety sensations and metabolic parameters while suppressing postprandial acylated ghrelin (60 minutes) and maintaining the resting energy expenditure.