Acute effects of dietary fibre and glycaemic carbohydrate on appetite and food intake in healthy males

The aim of this research was to describe the effect of equal weights of insoluble fibre (wheat bran) and glycaemic carbohydrate (glucose) on appetite and food intake over 1 and 2 h in healthy men. In a crossover design, high-fibre (F; 41 g insoluble fibre) cereal, low-fibre (W; 1 g fibre) cereal, F plus glucose (FG; 41 g glucose), and W plus glucose (WG; 41 g glucose) were administered to young men after an overnight fast. Treatments had similar fat, protein, volume and weight. In the first experiment, subjective appetite was measured at 15 min intervals before an ad libitum meal at 60 min. In the second experiment, subjective appetite was measured at 15 min intervals for the first 60 and 30 min intervals for the second 60 min before an ad libitum meal at 120 min. In experiment 1, ad libitum food intake was lower after the F, WG and FG cereals compared to W (3.1, 2.98, 2.96 and 3.59 MJ, respectively). Total energy intake (cereal + ad libitum) was lower after F compared to W and WG (4.1, 4.6, and 4.7 MJ, respectively). In experiment 2, the WG cereal significantly reduced ad libitum food intake compared to W (3.90 and 4.57 MJ, respectively). These results suggest that a serving of 41 g insoluble fibre reduces food intake independent of its weight and volume and similar to an equal weight of glucose within 60 min, but this effect is not maintained after 120 min.