To compare the effect of eating solid vs. drinking liquid forms of gelatin, sucrose and its component mixtures and whey protein on subjective appetite and food intake in young men.

Three randomized cross-over design experiments were used to compare the effect of solid and liquid forms of gelatin (6 g) in experiment 1, sucrose (75 g) and a mixture of 50% glucose/ 50% fructose (G50:F50) in experiment 2, and acid and sweet whey protein (50 g) in experiment 3 on healthy normal weight males . The controls were water (experiment 1 and 3) and calorie-free sweetened water with gelatin (sweet gelatin, experiment 1) or without gelatin (sweet control, experiment 2). Subjective average appetite was measured by visual analogue scales frequently over 1 h and ad libitum food intake was measured 1 h after the treatment consumptions.

Inclusion Criteria:

• Healthy lean males with BMI between 18- 24.9 kg/m2 and an age range of 19 to 28 years were recruited for the three experiments.

Exclusion Criteria:

• Diabetics (fasting blood glucose ≥ 7.0 mmol/L), smokers, breakfast skippers or dieters were excluded from the experiments. Individuals under medications or with a history of liver or kidney disease and major medical or surgical event within the last six months were excluded.