Abstract

Objectives:  To compare the effects of two cereal products differing by their slowly digestible starch (SDS) content and by their glycaemic index (GI) on plasma glucose and insulin (Experiment I) and on subjective satiety scores (Experiment II) when eaten as part of a realistic breakfast.

Design:  A randomised double-blind within-subject design with subjects eating the breakfast with a high SDS (HSDS) or low SDS (LSDS) cereal product in counter-balanced order.

Subjects:  Twelve healthy young adults (6 males, 6 females) participated in both Experiments I and II and 12 adults (6 males, 6 females) were added to participate in Experiment II.

Methods:  In Experiment I, blood samples were drawn prior to and at various rates over a postprandial interval of 240 min for plasma glucose and insulin assays. In Experiment II, hunger and gastric fullness scales were rated prior to and every 30 min over the same postprandial interval as in Experiment I.

Results:  In Experiment I, plasma glucose and insulin incremental areas under the curves (iAUC) over 120 min were lower in the HSDS than in the LSDS condition (P = 0.03 and P = 0.004 respectively). Total AUC over the 240 min (tAUC) for plasma insulin but not glucose was lower in the HSDS than in the LSDS condition (P = 0.01). At 240 min, plasma glucose concentrations were higher in the HSDS than in the LSDS condition (P = 0.04). In Experiment II, hunger ratings were lower and gastric fullness ratings higher in the HSDS than in the LSDS but this difference occurred mainly between 90 and 160 min.

Conclusions:  A cereal product with a high SDS content reduces the postprandial glucose and insulin responses and increases the satiety of a breakfast.

KEYWORDS: slowly digestible starch, glycaemic index, satiety, insulin, cereal products, glucose response