1.
Effect of glucomannan supplementation on body weight in overweight and obese children: protocol of a randomised controlled trial.
Zalewski, BM, Szajewska, H
BMJ open. 2015;(4):e007244
Abstract
INTRODUCTION Glucomannan (GNN), a water-soluble dietary fibre derived from the plant Amorphophallus konjac, is marketed for weight reduction. The exact mechanisms by which GNN might exert its actions are unclear. However, it has been shown that GNN slows gastric emptying by forming a viscous gel of large volume, which increases the feeling of satiety. Current evidence on the effectiveness of GNN for weight reduction is sparse, and well-designed trials performed in children are needed to assess the efficacy of this modality. We aim to systematically evaluate the efficacy of GNN consumption for the management of children who are overweight or obese. METHODS AND ANALYSIS Children aged 6-17 years who are overweight or obese (based on the WHO growth criteria) will be randomly assigned to receive GNN or placebo (maltodextrin) (both at a dose of 3 g/day) for 3 months and will be followed-up for 3 months. Before the intervention, all children will receive dietetic advice, and they will be encouraged to engage in physical activity. The primary outcome measure will be the body mass index-for-age z-score difference between the groups at the end of the intervention. ETHICS AND DISSEMINATION The study was approved by the Bioethics Committee of the Medical University of Warsaw. The findings of this trial will be submitted to a peer-reviewed journal (paediatric, nutrition or gastroenterology). Abstracts will be submitted to relevant national and international conferences. TRIAL REGISTRATION NUMBER NCT02280772.
2.
Effect of oligofructose supplementation on body weight in overweight and obese children: a randomised, double-blind, placebo-controlled trial.
Liber, A, Szajewska, H
The British journal of nutrition. 2014;(12):2068-74
Abstract
Limited evidence suggests that the dietary inclusion of oligofructose, an inulin-type fructan with prebiotic properties, may increase satiety and, thus, reduce energy intake and body weight in overweight and obese adults. The aim of the present study was to assess the effect of oligofructose supplementation for 12 weeks on the BMI of overweight and obese children. A total of ninety-seven children aged 7-18 years who were overweight and obese (BMI >85th percentile) were randomly assigned to receive placebo (maltodextrin) or oligofructose (both at an age-dependent dose: 8 g/d for children aged 7-11 years and 15 g/d for children aged 12-18 years) for 12 weeks. Before the intervention, all children received dietetic advice and they were encouraged to engage in physical activity. The primary outcome measure was the BMI-for-age z-score difference between the groups at the end of the intervention. Data from seventy-nine (81%) children were available for analysis. At 12 weeks, the BMI-for-age z-score difference did not differ between the experimental (n 40) and control (n 39) groups (mean difference 0.002, 95% CI - 0.11, 0.1). There were also no significant differences between the groups with regard to any of the secondary outcomes, such as the mean BMI-for-age z-score, percentage of body weight reduction and the difference in total body fat. Adverse effects were similar in both groups. In conclusion, oligofructose supplementation for 12 weeks has no effect on body weight in overweight and obese children.