The aim of the present study was to analyse the differences between the breakfast habits of obese/overweight (O) (those with body mass index [BMI] above the 75th percentile) and normal weight schoolchildren (N) (those with BMI equal to or below the 75th percentile). A seven consecutive days "food record" was used to record the intake of foods at breakfast and throughout the rest of the day. O subjects, and in particular female O subjects, omitted breakfast more frequently and took significantly smaller quantities of cereals than did N subjects. The energy supplied by breakfast, measured as a percentage of energy expenditure, was significantly lower in O subjects (17.0 +/- 8.5% in males and 14.6 +/- 6.1% in females) than in N subjects (20.9 +/- 9.4% in males and 17.6 +/- 6.5% in females). With respect to the energy and nutrients supplied by breakfast, O subjects took lower quantities of carbohydrates, thiamin, niacin, pyridoxine, vitamin D and iron than did N subjects. The energy profiles of O subjects breakfasts were more imbalanced than those of N subjects. A significant difference was seen between the amounts of energy supplied by carbohydrates. Without doubt, O subjects have less satisfactory breakfast habits than N subjects. This might be a reflection of whole diet that is less adequate, however, it is possible that an inadequate breakfast contributes to the making of poor food choices over the rest of the day, and, in the long term, to an increased risk of obesity.