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This paper describes the compilation of a special edition of the AUSNUT2011-2013 food composition database that includes glycemic index (GI) values. A 6-step, systematic methodology was used to assign GI to 5644 foods included in AUSNUT2011-2013. A total of 1752 (31%) foods were assigned a GI of 0 owing to low carbohydrate content; 363 (6%) had a direct match in 1 of the 4 data tables used; 1738 (31%) were assigned the GI of a 'closely related' food item; 1526 (27%) were assigned the weighted mean GI of ingredients; 205 (4%) were assigned the median GI of their corresponding food subgroup; 49 (<1%) were assigned a GI of 0 because they were not a significant source of carbohydrate in typical diets; and 5 (<1%) were assigned a default GI. We propose that this database should be used for all future Australian GI research until a subsequent version/update is compiled. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between glycemic index (GI), glycemic load (GL) and diabetes in a sample of older Australians. Design: 3654 people aged 49 years or older, representing 88% of permanent residents in the two postcode areas west of Sydney, underwent a detailed medical examination. The medical examination included a history of diabetes and associated risk factors. Fasting pathology tests, including plasma glucose, were obtained for 88% of the 3654 residents, and a 145-item semiquantitative food frequency questionnaire (FFQ) was completed by 89% of the residents. Outcomes: A history of diabetes was reported by 218 people (6%), including 111 (7%) men and 107 (5.2%) women. Another 66 (2.2%) people had a FBG ≥ 7.0 mM, indicating they had undiagnosed Type 2 diabetes. Therefore a total of 8.2% of people had diabetes, which is slightly higher than the estimate for Australian adults determined by the AusDiab study (7.5%). In addition to this, 127 (4.2%) people had impaired fasting glycaemia. The mean (±SD) GI and GL was calculated from the FFQ's and determined to be 56.5 (4.2) and 133 (45.8) units respectively. Valid food frequency data was available for 164 people with diabetes. People with diabetes had significantly lower mean GI (55.4±5.05 vs 56.34±4.16, P=0.007) and GL (118.4±41.15 vs 133.98±45.91, P<0.0001) than people who did not have diabetes. Conclusion: People with diabetes living in Australia choose a diet with a significantly lower average GI and GL than Australians who do not have diabetes. [ABSTRACT FROM AUTHOR]

Background: Dietary intervention in cystic fibrosis (CF) has historically focused on high-energy diets to address malnutrition, with little attention on diet quality. With increased survival, CF complications such as impaired glucose tolerance (IGT) and cystic fibrosis related diabetes (CFRD) have increased in prevalence. In the absence of consensus on the management of IGT, the role of dietary intake, specifically carbohydrate quality, requires consideration., Aims: The aims of this study were to: 1) determine nutritional quality of dietary intake at an adult CF clinic and compare this to the Australian Dietary Guidelines 2) explore relationships between dietary intake, including glycaemic index (GI) and glycaemic load (GL), and glucose response variables using continuous glucose monitoring (CGM)., Methods: Adults attending a Sydney hospital were recruited to undergo CGM for five-seven days and record dietary intake using a food record over the CGM period. The relationship between variables of dietary intake, including GI and GL and variables of glycaemic response, including mean amplitude of glycaemic excursions (MAGE), percentage of time in hyperglycaemic and euglycaemic range, were determined., Results: Eighteen participants completed the study with 87 full days of dietary and CGM data. Dietary intake was higher than recommendations in the Australian Dietary Guidelines in relation to grains and protein foods and only slightly higher in saturated fat. Bivariate correlations showed dietary GI was significantly positively associated with percentage of time in hyperglycaemic range. Dietary GL was significantly associated with SD, MAGE and percentage of time in euglycaemic range on CGM. Results remained significant when controlled for energy intake in partial correlation analyses., Conclusions: This study suggests GI and GL may be important dietary factors influencing glucose metabolism in CF. Further studies exploring low GI or GL diets as a dietary intervention in CF are the next step., Competing Interests: Conflict of Interest JBM is President of not-for-profit Glycaemic Index Foundation, director of a GI testing service and author of books about the GI., (Copyright © 2019 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Aims: The PREVIEW lifestyle intervention study (ClinicalTrials.gov Identifier: NCT01777893) is, to date, the largest, multinational study concerning prevention of type-2 diabetes. We hypothesized that the initial, fixed low-energy diet (LED) would induce different metabolic outcomes in men vs women., Materials and Methods: All participants followed a LED (3.4 MJ/810 kcal/daily) for 8 weeks (Cambridge Weight Plan). Participants were recruited from 8 sites in Europe, Australia and New Zealand. Those eligible for inclusion were overweight (BMI ≥ 25 kg/m 2 ) individuals with pre-diabetes according to ADA-criteria. Outcomes of interest included changes in insulin resistance, fat mass (FM), fat-free mass (FFM) and metabolic syndrome Z-score., Results: In total, 2224 individuals (1504 women, 720 men) attended the baseline visit and 2020 (90.8%) completed the follow-up visit. Following the LED, weight loss was 16% greater in men than in women (11.8% vs 10.3%, respectively) but improvements in insulin resistance were similar. HOMA-IR decreased by 1.50 ± 0.15 in men and by 1.35 ± 0.15 in women (ns). After adjusting for differences in weight loss, men had larger reductions in metabolic syndrome Z-score, C-peptide, FM and heart rate, while women had larger reductions in HDL cholesterol, FFM, hip circumference and pulse pressure. Following the LED, 35% of participants of both genders had reverted to normo-glycaemia., Conclusions: An 8-week LED induced different effects in women than in men. These findings are clinically important and suggest gender-specific changes after weight loss. It is important to investigate whether the greater decreases in FFM, hip circumference and HDL cholesterol in women after rapid weight loss compromise weight loss maintenance and future cardiovascular health., (© 2018 The Authors. Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)

Background/objectives: The effect of added sugar on health is a topical area of research. However, there is currently no analytical or other method to easily distinguish between added sugars and naturally occurring sugars in foods. This study aimed to develop a systematic methodology to estimate added sugar values on the basis of analytical data and ingredients of foods., Subjects/methods: A 10-step, stepwise protocol was developed, starting with objective measures (six steps) and followed by more subjective estimation (four steps) if insufficient objective data are available. The method developed was applied to an Australian food composition database (AUSNUT2007) as an example., Results: Out of the 3874 foods available in AUSNUT2007, 2977 foods (77%) were assigned an estimated value on the basis of objective measures (steps 1-6), and 897 (23%) were assigned a subjectively estimated value (steps 7-10). Repeatability analysis showed good repeatability for estimated values in this method., Conclusions: We propose that this method can be considered as a standardised approach for the estimation of added sugar content of foods to improve cross-study comparison.

Background: Puberty is a so-called critical period for overweight development and is characterized by physiological insulin resistance during mid-puberty. This study addressed the hypothesis that habitual consumption of a diet inducing higher levels of postprandial glycemia or insulinemia during puberty may have an unfavorable effect on the body composition in young adulthood., Methods: Multivariate regression analysis was performed on 262 participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study with at least two 3-day weighed dietary records during puberty (baseline: girls 9-14 years; boys 10-15 years) and anthropometric measurements in young adulthood (18-25 years). A published dietary glycemic index was assigned to each carbohydrate-containing food. Similarly, each food was assigned a food insulin index (insulinemic response to a 1 MJ portion of food relative to 1 MJ of glucose) using 121 values measured at Sydney University., Results: Dietary glycemic index or glycemic load during puberty was not related to body composition in young adulthood. In contrast, a higher dietary insulin index and a higher dietary insulin load during puberty were associated with higher levels of percentage of body fat (%BF) in young adulthood, even after adjustment for early life, socioeconomic and nutritional factors; %BF in energy-adjusted tertiles of dietary insulin index were 22.9 (95% confidence intervals (CI): 21.6, 24.1), 24.5 (23.2, 25.7), 24.7 (23.5, 25.9) %, P (for trend)=0.01; %BF in energy-adjusted tertiles of dietary insulin load were 22.8 (95% CI: 21.5, 24.0), 24.5 (23.2, 25.7), 24.8 (23.6, 26.0) %, P (for trend)=0.01. Adjustment for baseline %BF attenuated these relationships (P (for trend)=0.1 and=0.08, respectively). Dietary insulin demand was not related to body mass index., Conclusion: This study suggests a prospective adverse influence of dietary insulin demand during puberty on %BF in young adulthood. Postprandial increases in insulinemia rather than increases in glycemia appear to be implicated in an unfavorable development of body composition.

Our aim was to design a selection of foods with differing proportions of protein but equal palatability in two settings, Sydney Australia and Kingston Jamaica. The foods were manipulated to contain 10, 15 or 25% E as protein with reciprocal changes in carbohydrate to 60, 55 or 45% E and dietary fat was kept constant at 30%. Naïve participants did not identify a difference in protein between the versions. On average, the versions were rated equal in pleasantness (Sydney-10%: 44±2, 15%: 49±2 and 25%: 49±2 Kingston-10%: 41±3, 15%: 41±3 and 25%: 37±3).

Background and Purpose: It is unclear whether diets with high glycemic index (GI) and low cereal fiber (CF) are associated with greater risk of stroke. We aimed to assess the relationship between dietary GI and CF content, retinal microvasculature changes, and stroke-related mortality., Methods: The study consisted of a population-based cohort, 49+ years, examined at baseline (1992 to 1994). At baseline, participants completed validated food frequency questionnaires. Mean GI was calculated using an Australian database. Retinal arteriolar and venular diameters were measured from photographs. Mortality data were derived using the Australian National Death Index., Results: Over 13 years, 95 of 2897 participants (3.5%) died from stroke. Increasing GI (hazard ratio, 1.91; 95% CI, 1.01 to 3.47, highest versus lowest tertile) and decreasing CF (hazard ratio, 2.13; 95% CI, 1.19 to 3.80, lowest versus highest tertile) predicted greater risk of stroke death adjusting for multiple stroke risk factors. Persons consuming food in the highest GI tertile and lowest CF tertile had a 5-fold increased risk of stroke death (hazard ratio, 5.06; 95% CI, 1.67 to 15.22). Increasing GI and decreasing CF were also associated with retinal venular caliber widening (P(trend)<0.01). Adjustment for retinal venular caliber attenuated stroke death risk associated with high GI by 50% but did not affect the risk associated with low CF consumption., Conclusions: High-GI and low-CF diets predict greater stroke mortality and wider retinal venular caliber. The association between a high-GI diet and stroke death was partly explained by GI effects on retinal venular caliber, suggesting that a high-GI diet may produce deleterious anatomic changes in the microvasculature.

Background: Although dietary carbohydrates are thought to play a role in cataractogenesis, few epidemiologic studies have examined links between carbohydrate nutrition and cataract., Objectives: We investigated the associations between dietary glycemic index (GI), glycemic load (GL), total carbohydrate intake, and 10-y incident nuclear, cortical, and posterior subcapsular cataract., Design: Of 3654 baseline participants in an Australian population aged >/=49 y (1992-1994), 933 were seen after 5 and/or 10 y, had completed a detailed semiquantitative food-frequency questionnaire, had no previous cataract surgery or baseline cataract, and had photographs taken to assess incident cataract with the Wisconsin Cataract Grading System. Dietary information was collected with a validated food questionnaire. GI was calculated from a customized database of Australian foods. GI, GL, and all other nutrients were energy adjusted. Hazard ratios (HRs) and 95% CIs were calculated with the use of discrete logistic models., Results: After age, sex, diabetes, and other factors were controlled for, each SD increase in GI significantly predicted incident cortical cataract (HR: 1.19; 95% CI: 1.01, 1.39). Participants within the highest compared with the lowest quartile of GI were more likely to develop incident cortical cataract (HR: 1.77; 95% CI: 1.13, 2.78; P for trend = 0.035). These findings were similar after excluding participants with diabetes, although they were slightly attenuated and marginally nonsignificant (HR: 1.16; 95% CI: 0.98, 1.37, per SD increase in GI). No association was found between GI and nuclear or posterior subcapsular cataract and between GL or carbohydrate quantity and any cataract subtype., Conclusion: In an Australian cohort, poorer dietary carbohydrate quality, reflected by high GI, predicted incident cortical cataract.

Both postprandial hyperglycemia and insulin resistance (IR) have implications for the development of cardiovascular disease. The present study was designed to examine differences in postprandial glycemia and insulin sensitivity among young adults of different ethnic origins. Lean, healthy subjects (n = 60) from five ethnic groups [20 European Caucasians, 10 Chinese, 10 South East (SE) Asians, 10 Asian Indians and 10 Arabic Caucasians] were matched for age, body mass index, waist circumference, birth weight and current diet. A 75-g white bread carbohydrate challenge was fed to assess postprandial glycemia and insulinemia. Insulin sensitivity was assessed in three groups by the euglycemic-hyperinsulinemic clamp and in all subjects by homeostasis model assessment (HOMA) modeling. Postprandial hyperglycemia (incremental area under the curve) and insulin sensitivity (M-value) both showed a twofold variation among the groups (P < 0.001) and were significantly related to each other (R(2) = 56%, P < 0.001). Young SE Asians had the highest postprandial glycemia and lowest insulin sensitivity, whereas European and Arabic Caucasian subjects were the most insulin sensitive and carbohydrate tolerant. These findings suggest that IR is evident even in lean, young adults of some ethnic groups and is associated with significant increases in postprandial glycemia and insulinemia in response to a realistic carbohydrate load.

Objective: To determine and compare the glycaemic index (GI) values of a range of Vietnamese foods in two racial groups., Design and Subjects: Twelve healthy subjects (six Asian and six Caucasian) consumed 50 g carbohydrate portions of a reference food (glucose sugar) and nine Vietnamese foods (three rices, three noodle products and three sweet foods) in random order after an overnight fast. The reference food was tested on two separate occasions, and the Vietnamese foods were each tested once. Capillary blood samples were taken at time 0 (fasting), 15, 30, 45, 60, 90 and 120 min from the start of each meal. Samples were analysed for plasma glucose and the incremental areas under the plasma glucose curves (AUC) were used to calculate the GI values of the test foods, using glucose as the reference food (ie GI value of glucose=100). The mean GI value of each food was calculated for the entire group of subjects (n=12) and for both racial groups (n=6)., Results: The three rices had surprisingly high GI values (86-109), whereas the noodle products had relatively low GI values (39-61). The sugar-rich foods produced intermediate GI values (54-79). The GI values for the nine foods calculated separately for the two racial groups were not significantly different from each other (P=0.26)., Conclusions: The GI values derived from Caucasian subjects are likely to be applicable to Asian populations. Varieties of imported rice from Thailand were found to have high GI values. Alternative low-GI staples, such as rice noodles, may be preferable for Asian/Vietnamese people with diabetes., Sponsorship: This study was funded by the University of Sydney.

Background: In animal studies, sialic acid supplementation is associated with increases of gangliosides in the brain and improved learning ability. Only limited data are available on the sialic acid content of human milk and infant formulas., Objective: We compared the concentrations of oligosaccharide-bound, protein-bound, and free sialic acid in milk from mothers of full-term and preterm infants and in a range of infant formulas., Design: The milk from 20 and 14 mothers of full-term and preterm infants (mean gestational age: 31 +/- 3 wk), respectively, was collected at 4 stages of lactation (colostrum, transition, 1 mo, and 3 mo) and compared with 21 different infant formulas., Results: Total sialic acid concentrations were highest in colostrum (x +/- SEM: 5.04 +/- 0.21 mmol/L in full term) and decreased by nearly 80% over the next 3 mo. Human milk from mothers of preterm infants contained 13-23% more sialic acid than did milk from mothers of full-term infants at 3 of the 4 lactation stages (P < 0.02). The sialic acid content of most formulas was <25% of that found in mature human milk (P < 0.01). Most of the sialic acid in the formulas ( approximately 70%) was bound to glycoproteins, whereas in human milk most sialic acid was bound to free oligosaccharides., Conclusions: Human milk, including milk from mothers of preterm infants, is a rich source of oligosaccharide-bound sialic acid, which contrasts with the relatively small amounts found in infant formulas. The nutritional significance of sialic acid is presently unknown, but it is plausible that it is a conditional nutrient that contributes to sialic acid accretion in the brain.