Evidence indicates that postprandial glucose concentrations may be manipulated by reducing energy consumption at dinner and increasing energy intake at breakfast. It is possible that the effects may be largest for dysglycaemic individuals, particularly those who are inactive on a daily basis. We aim to test the hypothesis that an increased energy intake at breakfast can improve blood glucose metabolism during periods of prolonged sitting in overweight/obese men and women with prediabetes.
To date, nine adults (age: 58 ± 5 y, BMI: 33 ± 4 kg/m2) with prediabetes (IFG and/or IGT) have completed two 10 h laboratory visits in a randomized order consisting of sitting uninterrupted for breakfast, lunch and dinner meals of either 20%/30%/50% energy intake (Dinner condition) or 50%/30%/20% energy intake (Breakfast condition), respectively, with the same meal composition (50% carbohydrate, 20% protein, 30% fat). Continuous glucose monitors (CGM) measured interstitial [glucose] from 0800 on a trial day to 0800 the morning after.
The total 24 h area under the curve (AUC) [glucose] was not different between conditions (P=0.49) nor was the mean amplitude of glucose excursions (MAGE; P=0.22). The incremental AUC (iAUC) between breakfast and lunch was higher in the Breakfast condition (P=0.01) but between lunch and dinner was greater for the Dinner condition (P=0.001). No difference in iAUC between conditions from dinner to 0800 the following day (P=0.08) was observed.
Our preliminary findings indicate that while the total 24 h AUC and the MAGE do not support a difference in blood glucose regulation in response to a large breakfast, a more consistent blood glucose concentration profile was observed across a day in the Breakfast condition. These findings suggest that a larger breakfast balanced by a smaller dinner may hold some benefit for the acute regulation of blood glucose during prolonged sedentary behavior in dysglycaemic individuals.