Viscosity of fiber preloads affects food intake in adolescents
Received 27 June 2008; received in revised form 11 September 2008; accepted 16 September 2008. published online 22 January 2009.
Abstract
Background and aims
Dietary fiber that develops viscosity in the gastrointestinal tract is capable of addressing various aspects of food intake control. The aim of this study was to assess subsequent food intake and appetite in relation to the level of viscosity following three liquid preloads each containing 5g of either a high (novel viscous polysaccharide; NVP), medium (glucomannan; GLM), or low (cellulose; CE) viscosity fiber.
Methods and results
In this double-blind, randomized, controlled and crossover trial, 31 healthy weight adolescents (25 F:6 M; age 16.1±0.6 years; BMI 22.2±3.7kg/m2) consumed one of the three preloads 90min prior to an ad libitum pizza meal. Preloads were identical in taste, appearance, nutrient content and quantity of fiber, but different in their viscosities (10, 410, and 700poise for CE, GLM, and NVP, respectively). Pizza intake was significantly lower (p=0.008) after consumption of the high-viscosity NVP (278±111g) compared to the medium-viscosity GLM (313±123g) and low-viscosity CE (316±138g) preloads, with no difference between the GLM and CE preloads. Appetite scores, physical symptoms and 24-h intake did not differ among treatment groups.
Conclusion
A highly viscous NVP preload leads to reduced subsequent food intake, in terms of both gram weight and calories, in healthy weight adolescents. This study provides preliminary evidence of an independent contribution of viscosity on food intake and may form a basis for further studies on factors influencing food intake in adolescents.
aDepartment of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
bDepartment of Medicine, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
cClinical Nutrition and Risk Factor Modification Center, St. Michael's Hospital and Li Ka Shing Knowledge Institute, Toronto, Ontario, Canada
dCanadian Centre for Functional Medicine, Coquitlam and Food, Nutrition and Health Program, Faculty of Land and Food Systems, University of British Colombia, Vancouver, British Columbia, Canada
eDivision of Endocrinology and Metabolism, St. Michael's Hospital, Toronto, Ontario, Canada
Corresponding author. Clinical Nutrition and Risk Factor Modification Centre, St Michaels’ Hospital, 70 Richmond St E, Suite 100, Ontario, M5C 1N8 Canada. Tel.: +1 416 864 5525; fax: +1 416 864 5538.
ABSTRACT