Dissociation of the glycaemic and insulinaemic responses to whole and skimmed milk

In most carbohydrate-containing foods, the blood insulin response is predictable and is closely linked to the food's glycaemic index ( GI). A single study, examining whole milk and fermented milk products made from whole milk, recently reported a large dissociation between the GI and insulinaemic index ( II) in healthy normal adults. Because the fat component of a food may influence the GI and II, it is unclear if a similar dissociation may exist for skimmed milk in normal adults. We determined the GI and II of both skimmed and whole milk in nine healthy, male ( n 6) and female ( n 3) subjects ( 23.6 ( SD 1.4) years). No significant ( P > 0.05) differences existed between GI and II for skimmed and whole milks. Significant ( P < 0.05) differences were observed between the actual and predicted areas under the insulin curves for both skimmed milk ( predicted 1405 ( SD 289) pmol x min/1; actual 6152 ( SD 1177) pmol x min/1) and whole milk ( predicted 1564 ( SD 339) pmol x min/1; actual 5939 ( SD 1095) pmol x min/1). Consequently, a large and similar dissociation of the GI and II existed for both whole milk ( 42 ( SD 5) and 148 ( SD 14)) and skimmed milk ( 37 ( SD 9) and 140 ( SD 13)). It is concluded that the dissociation of the GI and II in milk is not related to its fat content.