For 7 d six volunteers consumed at breakfast a 50-g starch meal prepared from either potato-flakes bran or instant bean flakes. These meals were isocaloric and had the same analytical composition. The metabolic effect of the meals on plasma glucose and insulin levels and on energy expenditure were assessed over 6 h on days 1 and 7 of each diet period. No significant differences in the shape and magnitude of plasma glucose and insulin responses were observed between days 1 and 7 of the same diet. Maximum glucose and insulin responses were significantly lower after the bean meal than after the potato meal. Although each meal tested was digested at a different rate, substrate oxidation and energy expenditure over 6 h were very similar.