As a glucose containing drink has been reported to improve memory, and missing breakfast has been reported to adversely influence memory late in the morning, meals designed to differ in their ability to release glucose into the blood stream were contrasted. Using a factorial design, breakfasts containing 15, 30 or 50 g of carbohydrate and 1.5, 6 or 13 g of fibre were compared. The glucose tolerance of participants proved to be an important factor. Those with better tolerance reported better mood. Those eating breakfasts containing greater amounts of carbohydrate reported feeling tired rather than energetic. The amount of carbohydrate did not negatively affect memory in those with better glucose tolerance, however, the consumption of more carbohydrate resulted in more forgetting in those with poorer glucose tolerance. The effect with reactions times differed from memory in that a greater intake of carbohydrate resulted in faster responses later in the morning.