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Objective Low glycemic index (GI) foods have been suggested to minimize large fluctuations in blood glucose levels and reduce food intake. However, the majority of studies have been conducted on Caucasian populations with limited data on Asians. The objective of this study was to investigate how the provision of a low GI breakfast and afternoon snack affected daily blood glucose profiles and food intake. Materials and methods In a randomized, controlled crossover non blind design, 11 healthy Chinese male adults (body mass index 22.4 ± 1.3 kg m−2) attended two sessions where they consumed either a high or low GI breakfast and afternoon snack, and a standardized buffet lunch. Daily changes in glycemic response (GR) were measured using the Medtronic MiniMed (Northridge, CA) iPro™2 continuous glucose monitoring system (CGMS). The GR was further calculated to obtain the incremental area under the curve (IAUC). Glycemic variability was calculated as mean amplitude of glycemic excursion (MAGE) and energy intake (kcal) was measured quantitatively at the buffet lunch. Results Compared to the high GI intervention, the low GI intervention significantly reduced the GR following breakfast (p = 0.02), lunch (p = 0.02) and dinner (p = 0.05). The low GI treatment showed a reduction in daily AUC (p = 0.03). There was a significant reduction in IAUC after a low GI breakfast compared to the high GI breakfast (p = 0.03). The low GI breakfast resulted in a significantly lower food intake at lunch and a resulting decreased energy intake of 285 kcal (p = 0.02). The MAGE was significantly lower during the entire low GI treatment (p = 0.03). Conclusions Consumption of a low GI breakfast and afternoon snack was capable of attenuating 24-h blood glucose profiles, minimize glycemic excursions and reduce food intake in healthy Asian males. This simple dietary intervention may be an acceptable approach in improving overall glycemia and energy balance in Asians. Clinical trial registration number NCT02340507, Highlights • The impact of low and high glycemic index foods on 24 h blood glucose profile. • The CGMS provides detailed information on how diets affect longer term glycemia. • Low GI breakfast and afternoon snack minimize large blood glucose fluctuations. • Low GI foods reduce glycemic variability and total energy intake.

article i nfo Article history: Received 7 October 2011 Accepted 25 February 2012 In vitro, the addition of lipids to a carbohydrate food has been found to increase the digestibility of starch. In contrast, in vivo studies have shown that the addition of fat to a food can reduce the glycaemic response (GR). The aim of this study was to assess if delayed gastric emptying (GE) causes reduced GR with the addition of lipids to a carbohydrate food and if a relationship between GR and in vitro digestion of starch exists for high fat foods. Ten healthy volunteers were tested on five occasions after consuming pancakes containing 50 g of available carbohydrate and 202 kcal of sunflower oil, olive oil, butter, medium chain triglyceride (MCT) oil or a control containing no oil. GR was measured using fingerpick blood samples, satiety using visual analogue scales and GE using the 13 C octanoic acid breath test. There was a significant difference in GR between the different pancake breakfasts (p=0.05). The highest GR was observed following the control pancakes and the lowest following the olive oil pancakes. There were significant differences in GE half time, lag phase and ascension time (pb0.05) between the different pancakes with the control pancakes having the shortest GE time and the MCT pancakes the longest. There was a significant difference in satiety parameters fullness (p=0.003) and prospective consumption (p=0.050), with satiety being lowest following the control pancakes. There was a significant inverse correlation between the GR and all satiety parameters. A significant inverse correlation (p=0.009) was also observed between the digestibility of starch in vitro and GR in vivo. The paper indicates that the digestibility of starch in vitro does not predict the GR for high fat containing foods.

The effect of replacement of crude malva nut gum (CMG) at 0%, 2.5%, 5%, 7.5% and 10% w/w on pasting behaviour, textural properties and freeze–thaw stability of wheat flour was investigated. Replacement of wheat flour by CMG significantly elevated (p

The glycemic response (GR) to food is influenced by both intrinsic and extrinsic factors. A consistent observation in GR studies is the wide within- and between-individual variations. The authors hypothesize that between-individual variations in the GR, insulin response (IR) and gastric emptying occur even when food particle size is standardized. Volunteers were tested on 2 nonconsecutive days after an overnight fast in randomized order. On 1 day, the volunteers consumed large (>2000 μm) rice particles, and on the second day, small rice particles (500-1000 μm). Subsequently, gastric emptying using the sodium [(13)C] acetate breath test (for 240 minutes) and GR and IR (for 120 minutes) from finger-prick blood samples were measured. The incremental area under the curve (IAUC) for the GR for small particles varied 45% more compared with whole rice. The small particles elicited a significantly greater GR IAUC than the large particles. The standard deviations associated with the IR IAUC for the small particles was 140% greater than that of the large particles. The total IAUC for IR was also significantly greater for the small particles than the large particles. The between-individual variations associated with gastric emptying times were similar for both samples. The gastric emptying latency phase, lag, and half time were significantly shorter for the small particles. Ingesting small particles causes faster gastric emptying and produces greater glycemic and IRs. Between-individual variations in GR and IR can be observed even when all the food associated factors including ingested particle size (mastication) are controlled for in humans.

The degree of mastication varies significantly between individuals and may be a cause for the considerable interindividual variation observed in the glycemic response (GR) to a single food. Using rice as the model, the aim of this study was to determine if interindividual differences in mastication and resulting degree of particle breakdown affected in vitro and in vivo glycemic potency. In a randomized crossover design, using 15 subjects, the particle size distribution and in vitro digestibility of individuals' chewed rice were determined along with their in vivo blood GR. The rapidly digested starch (RDS) content in the masticated boluses, moreover, was measured during in vitro digestion. The particle size distribution of masticated rice differed significantly interindividually. In vitro digestion of rice decreased as particle size increased. The degree of particle size breakdown as a result of mastication correlated with the RDS content in the chewed food bolus and initial digestion rate in vitro. The quantity of undigested material remaining at the end of 120-minute in vitro digestion correlated significantly with the percentage of particles greater than 2000 microm in masticated rice. The percentage of particles smaller than 500 microm correlated significantly with in vivo GR at 30 minutes postingestion but not with the total incremental area under the blood glucose curve. The degree of habitual mastication may therefore potentially influence both the magnitude and pattern of the GR and may partly explain interindividual differences in it. Although the study sets the base for future research, firm conclusions can be reached only upon the completion of additional work.

Food products incorporated with soluble dietary fiber beta-glucan have shown varying effects on postprandial glycemia. The objective of the present study was to test the hypothesis that a food product fortified with barley beta-glucan and subjected to minimum processing and mild cooking might be effective in lowering glycemic response. In a randomized, single-blind, controlled crossover trial, 8 healthy human subjects (3 men, 5 women; aged 26-50 years; body mass index