OBJECTIVE: To study the effect of simple vs complex carbohydrates (SCHO and CCHO respectively) containing breakfasts on blood parameters, hunger and satiety and mood. DESIGN: A 2-day, open, randomised, cross-over trial. SUBJECTS: A total of 26 male subjects (34±6y; BMI 23.4±2.2 kg m-2). MEASUREMENTS: Blood glucose, insulin, triacylglycerols (TG), free fatty acids (FFA) and cholecystokinin (CCK) were determined repeatedly for 4 h on both test days after a breakfast containing SCHO or CCHO. Feelings of hunger and satiety were determined at similar time points as well. Mood state was examined 3 h after breakfast consumption. RESULTS: Consumption of a SCHO breakfast resulted in higher glucose and insulin levels at 30 min after breakfast consumption. TG at 180 min, and FFA at 180 and 240 min were higher after SCHO breakfast than after CCHO breakfast. Satiety scores were higher after CCHO breakfast consumption for the first 90 min after intake. Furthermore, the item 'fatigue' was scored higher after SCHO breakfast than after CCHO breakfast intake. CONCLUSION: Consumption of a CCHO breakfast is favourable in comparison to a SCHO breakfast, because of the lower perception of 'fatigue' and the higher degree of satiety after consumption.