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Despite considerable research the evidence around the antidiabetic properties of cinnamon remains equivocal, and this may be due to varietal differences which is an aspect that is understudied. This study systematically compared the anti-hyperglycaemic properties of the four major commercial cinnamon types used around the world (Chinese; Cinnamomum cassia [CC], Indonesian; C. burmanii [IC], Vietnamese; C. loureirii [VC], and Ceylon; C. zeylanicum [SC]). LC-MS analysis showed distinct diffrences in the phytochemical profiles of cinnamon with SC showing the lowest coumarin concentration. CC and IC had the highest polyphenol levels and antioxidant potential, and all four types differed significantly in their content (P

The addition of vegetable to carbohydrate-based meals has been shown to improve postprandial glucose homeostasis. Inter-individual variation in responses preclude conclusive evidence, particularly in women. The sirtuins and associated genes involved in producing the chemical, nicotinamide adenine dinucleotide (NAD), are emerging as key players in blood glucose control and may contribute to variable responses. This study aimed to investigate effects of co-ingesting green leafy vegetables (GLV) on postprandial glucose regulation following a carbohydrate meal and factors affecting inter-individual variation particularly around the sirtuin system.Twenty-five women (BMI 24.8–30.5 kg/m2) were recruited to ‘The impact of Vegetables’ (VegGI) study on acute glycaemia and Glycaemia induced CVD risk in women: metabolic effects and Inter-individual variations. Postprandial glycaemic responses (GR) following rice (75 g of available carbohydrate), rice with bok choy (150g) or spinach (150g) were measured every 5 minutes for 4 hours using a Continuous Glucose Monitoring system (Medtronic Ltd). Anthropometric, cholesterol (Cholestech LDX, Alere), HbA1c (Afinion AS100, Alere) and insulin (Mercodia AB) measures were made in a fasted state. Oestradiol, progesterone, follicular stimulating hormone and testosterone were measured (ADVIA Centaur). Total RNA was extracted from postprandial blood collected at 0 h, 30 min, 1 h and 2 h in PAXgene blood RNA tubes (PreAnalytiX GmbH) using a Blood RNA Kit (Qiagen, Crawley, UK) and quality assessed by Agilent Bioanalyser (Agilent Technologies, Bracknell, UK). Gene expression was measured using the GenomeLab System and a custom designed multiplex assay, the hSIRTNADPlex (25 targets involved in the sirtuin signalling).Linear mixed models (ver.24.0; SPSS Inc) revealed no effect of GLV consumption on postprandial GR. Principal component analysis (SIMCA-P + 12.0 software, MKS Instruments UK Ltd.) of postprandial GR indicated inter-individual variation in the responses associated with the test meals. Partial Least Square (PLS) stratified the cohort into two subgroups based on sirtuin system gene expression profiles. Postprandial GR was a contributing factor in the stratification observed, together with BMI, plasma lipid, insulin and glucose levels, but not menopausal status.Preliminary evidence indicates that co-ingesting GLV with a carbohydrate meal does not reduce postprandial GR in women (BMI 24.8–30.5 kg/m2) and that significant inter-individual variation in postprandial GR may be linked to the sirtuin system, BMI, plasma lipid, insulin, and glucose levels but not menopausal status. Recruitment and data analysis are ongoing to increase group size and further assess contributing factors.This work was supported by Scottish Government's Rural and Environment Science and Analytical Services Division

Scope Green leafy vegetables (GLV) may improve postprandial glycaemic responses (PGR) and metabolic health. However, inter-individual variations (IIV) preclude conclusive evidence. Sirtuin system is emerging as a key player in blood glucose control. This study investigated IIV in PGR in women co-ingesting GLV with a carbohydrate meal and interactions with the sirtuin system. Methods and results Volunteers (n = 31 women) consumed rice, rice with bok choy or spinach (75g available carbohydrate) on separate occasions. Postprandial glucose, insulin, adropin and lipid levels were measured. Anthropometric measurements and sex hormones were measured. GeXP assay measured whole blood postprandial gene expression profiles of 25 markers involved in sirtuin signalling. GLV consumption had no significant effect on PGR which showed high variation. PGR correlated with age, but no other consistent associations were observed. Sirtuin gene expression profiles revealed distinct stratified subgroups associated with PGR, lipid, insulin, fat mass, waist/hip circumferences and adropin levels. Conclusion PGR to co-ingesting GLV with a carbohydrate meal were highly variable in this cohort and failed to reveal a significant reduction in PGR. Variable responses were largely independent of menopausal status and meal consumed. However, lower expression of sirtuin gene targets was associated with higher PGR and with markers linked to health status. This article is protected by copyright. All rights reserved.

Bread has become a widely consumed staple food in South-east Asia. However, there is very little data on the glycaemic potential of local commercial breads. The objective of this study was to comparatively assess the glycaemic potential of some commonly consumed commercial breads using a validated in vitro model. Sixteen types of breads representing the most popular brands and types were evaluated. The results showed that white and enriched white breads had a greater glycaemic potential than wholemeal breads (rapidly digestible starch (RDS) content450 mg of glucose/g of sample). The lowest glycaemic potential was observed for wholegrain breads (RDS content375 mg of glucose/g of sample). The glycaemic impact of some specialty breads such as pandan bread, milk bread and corn loaf was also examined. Whist the data show that South-east Asian breads have notably differential effects on glycaemia, it highlights the need to formulate Asian dietary guidelines for bread which will enable better food choice and glycaemic control.

Aqueous extracts (20% w/w) of dried berry fruits and skins were used as sources of phenolic compounds to fortify yogurt beverages. The total phenol and anthocyanin content of the reformulated yogurts were determined, and the antioxidant properties were compared to plain yogurt (C) during storage at 4 °C for a total period of four weeks. Yogurt beverages fortified with salal berry (SB) extracts contained higher amounts of phenolic compounds (>69.9 μg GAE/mL) and anthocyanins (>19.12 mg C3G/L) compared to drinks supplemented with blackcurrant pomace (BC) extract (>50.13 μg GAE/mL and >10.80 mg C3G/L respectively). Storage affected the stability of anthocyanins, whereas total phenol content remained unaffected. Yogurts with SB displayed the highest antioxidant capacity followed by samples with BC, which is attributed to the radical scavenging effect of the bioactive compounds present with antioxidant properties. The antioxidant capacity of the yogurt beverages fortified with fruit extracts was maintained during cold storage. Findings of this study indicate that SB and BC pomace can be used as functional ingredients to increase the antioxidant potential of yogurt beverages.

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.

The objective of the present study was to determine the glycaemic index (GI) and glycaemic load (GL) values of standard portion sizes of Southeast Asian traditional foods. A total of fifteen popular Southeast Asian foods were evaluated. Of these foods, three were soft drinks, while the other twelve were solid foods commonly consumed in this region. In total, forty-seven healthy participants (eighteen males and twenty-nine females) volunteered to consume either glucose at least twice or one of the fifteen test foods after a 10–12 h overnight fast. Blood glucose concentrations were analysed before consumption of the test food, and 15, 30, 45, 60, 90 and 120 min after food consumption, using capillary blood samples. The GI value of each test food was calculated by expressing the incremental area under the blood glucose response curve (IAUC) value of the test food as a percentage of each participant's average IAUC value, with glucose as the reference food. Among the fifteen foods tested, six belonged to low-GI foods (Ice Green Tea, Beehoon, Pandan Waffle, Curry Puff, Youtiao and Kaya Butter Toast), three belonged to medium-GI foods (Barley Drink, Char Siew Pau and Nasi Lemak), and the other six belonged to high-GI foods (Ice Lemon Tea, Chinese Carrot Cake, Chinese Yam Cake, Chee Cheong Fun, Lo Mai Gai and Pink Rice Cake). The GI and GL values of these traditional foods provide valuable information to consumers, researchers and dietitians on the optimal food choice for glycaemic control. Moreover, our dataset provides GI values of fifteen foods that were not previously tested extensively, and it presents values of foods commonly consumed in Southeast Asia.

Rice is the principle staple and energy source for nearly half the world's population and therefore has significant nutrition and health implications. Rice is generally considered a high glycemic index (GI) food, however, this depends on varietal, compositional, processing, and accompaniment factors. Being a major contributor to the glycemic load in rice eating populations, there is increasing concern that the rising prevalence of insulin resistance is as a result of the consumption of large amounts of rice. Devising ways and means of reducing the glycemic impact of rice is therefore imperative. This review gathers studies examining the GI of rice and rice products and provides a critical overview of the current state of the art. A table collating published GI values for rice and rice products is also included.

White rice is the main staple for the majority in the world. The effects of protein, fat and vegetables on the glycaemic and insulinaemic responses to a white rice-based meal have not been reported. The aim of this study was to determine the effect of co-ingesting a high-protein food (breast chicken), a fat (ground nut oil), a leafy vegetable or all three on the glycaemic and insulinaemic responses of white rice in healthy adults.This was a randomized crossover trial conducted at the Clinical Nutrition Research Centre in Singapore. Twelve healthy volunteers were given five test meals (white rice alone, white rice with chicken, white rice with oil, white rice with vegetable and white rice with chicken, oil and vegetable) once and the reference food (glucose solution) three times in a random order at 1-week intervals. Capillary blood samples were then drawn serially for 3 h, and glucose and insulin were analysed.The glycaemic response (GR) to white rice with chicken breast, ground nut oil and vegetable was significantly lower than to white rice alone. The glycaemic index (GI) of pure white rice was 96, whereas combined with chicken breast, ground nut oil and vegetable, it was 50. The addition of oil delayed the peak glucose response and reduced the iAUC, resulting in a GI value of 67. The addition of chicken and vegetable resulted in a GI value of 73 and 82, respectively. The insulinaemic index (II) of the white rice-based meals varied between 54 and 89. Chicken breast in the meal increased the insulinaemic response and decreased the GR. White rice II was lower than the glucose control, which indicated that the former was not as insulinogenic as the latter. White rice with vegetable had the lowest II.Co-ingesting chicken, oil or vegetable with white rice considerably influences its glycaemic and insulinaemic responses. Co-ingesting white rice with all three components attenuates the GR to a greater degree than when it is eaten with any single one of them, and that this is not at the cost of an increased demand for insulin.

Dietary proteins are essential for the life of all animals and humans at all stages of the life cycle. They serve many structural and biochemical functions and have significant effects on health and wellbeing. Dietary protein consumption has shown an upward trend in developed countries in the past two decades primarily due to greater supply and affordability. Consumption is also on the rise in developing countries as affluence is increasing. Research shows that proteins have a notable impact on glucose homeostasis mechanisms, predominantly through their effects on insulin, incretins, gluconeogenesis, and gastric emptying. Since higher protein consumption and impaired glucose tolerance can be commonly seen in the same population demographics, a thorough understanding of the former's role in glucose homeostasis is crucial both toward the prevention and management of the latter. This chapter reviews the current state of the art on proteins, amino acids, and their effects on blood glucose and insulin secretion.

Acknowledgment This work is part of the Strategic Research 2011–2016 and is funded by the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS).