Correlation between dietary glycemic index and cardiovascular disease risk factors among Japanese women

Glycemic index, glycemic load, dietary insulin index, and dietary insulin load in relation to cardiometabolic risk factors among participants with atherosclerosis: a cross-sectional study

BACKGROUND

We examined the cross-sectional associations of dietary Glycemic Index (GI), Glycemic Load (GL), Dietary Insulin Index (DII), and Dietary Insulin Load (DIL) with cardiovascular disease (CVD) factors in subjects with atherosclerosis.

METHODS

The present cross-sectional study was conducted on subjects with atherosclerosis. Regular dietary intake was assessed using a 168-item semi-quantitative food frequency questionnaire (FFQ) and GI, GL, DIL, and DII were also calculated. Odds Ratio (OR) and 95% Confidence Intervals (CIs) were estimated for general and central obesity according to the GI, GL, DII, and DIL.

RESULTS

According to the continuous score of GL, there was a significant positive association between GL and central obesity for women in all models. Regarding the association between DIL score and biochemical variables, there was a significant positive association between Na and Aspartate transaminase (AST) with DII. Moreover, there was a significant positive association between LDL-c(p = 0.03) and AST (p = 0.04)with DIL score in all 3 models.

CONCLUSION

In this study, GL was associated with greater odds of central obesity in women, but not in men. Neither dietary DII nor DIL was associated with BMI and central obesity. GI, GL, DII, and DIL were significantly associated with some CVD risk biomarkers in subjects with atherosclerosis.

Dietary insulin index and load in relation to cardiometabolic risk factors in patients with type 2 diabetes mellitus: A cross-sectional study on the RaNCD cohort study

OBJECTIVES

The aim of the present study was to evaluate the link between the dietary insulin index (DII) and dietary insulin load (DIL) and cardiometabolic risk factors in patients with type 2 diabetes mellitus (T2DM).

METHOD

In this cross-sectional population-based study, 827 participants with diabetes were included based on the RaNCD (Ravansar Non-Communicable Disease) cohort study baseline data. DII and DIL were calculated based on standard formulas using food insulin index values published earlier. Logistic regression analysis was used to determine the association of DII and DIL with cardiovascular risk factors.

RESULTS

A significantly direct association was shown between DII and metabolic syndrome (MetS; odds ratio [OR], 1.32; 95% confidence interval [CI], 1.05-2.50). The odds of developing abdominal obesity in patients with the highest DII were almost twice as high as those with the lowest DII (OR, 2.06; 95% CI, 1.02-4.99). Patients in the top quintile of DIL had twice the odds of being obese than those in the bottom quintile. Furthermore, positive associations were found between DIL and both MetS (OR, 1.98; 95% CI, 1.10-4.21) and waist circumference (OR, 2.90; 95% CI, 1.10-7.20).

CONCLUSION

Higher DII and DIL were positively related to greater risks for both MetS and abdominal obesity among patients with T2DM. Additionally, higher DIL was associated with a higher risk for obesity in the Ravansar population. However, further prospective investigations are needed to clarify the cause-and-effect link between DII, DIL, and cardiovascular risk factors in patients with T2DM.

The Role of Dietary Glycemic Index and Glycemic Load in Mediating Genetic Susceptibility via MC4R s17782313 Genotypes to Affect Cardiometabolic Risk Factors among Apparently Healthy Obese Individuals

Background

The association of genetic and dietary factors with occurrence and progression of chronic diseases such as metabolic syndrome (MetS) has long been addressed but there is a lack of evidence for complex interrelationships, including direct and indirect effects of these variables. Hence, this study is aimed at evaluating the mediating role of glycemic indices in the association of melanocortin-4 receptor (MC4R) rs17782313 polymorphism, sociodemographic, and psychological factors with the risk of MetS in obese adults using structural equation modeling.

Methods

We performed a cross-sectional analysis of data from 287 apparently healthy adults. Dietary glycemic index (GI) and glycemic load (GL) were calculated from a validated 147-item food frequency questionnaire (FFQ). MC4R s17782313 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Structural equation modeling was used to explore direct and indirect effects of genetic and nongenetic factors on MetS.

Results

MC4R gene variant was directly associated with the risk of MetS (B = 0.010; P = 0.023). On the other hand, this variant was found to be indirectly and positively associated with LDL-C (B = 6.589; P = 0.042) through mediatory effects of GI and GL. Moreover, GI and GL also mediated indirect positive effects of sex and age on LDL-C (B = 3.970; P ≤ 0.01; B = 0.878; P ≤ 0.01, respectively) and HDL (B = 2.203; P ≤ 0.01; B = 0.129; P ≤ 0.01, respectively). MC4R rs17782313 polymorphism had positive effects on GI (B = 1.577; P ≤ 0.01) and GL (B = 1.235; P ≤ 0.01).

Conclusion

Our data may state a hypothesis of the mediating effect of quantity and quality of carbohydrates consumed in relationship between genetic susceptibility to obesity and cardiometabolic risk factors. Further analyses should be carried out in high-quality cohort studies in order to confirm the findings.

The association between dietary glycemic index and cardio-metabolic risk factors in obese individuals

Background:

The dietary glycemic index (GI) has been introduced as a novel index to elucidate the potential of foods to increase postprandial glucose. According to the limited available data about the association of GI with cardio-metabolic risk factors such as lipid profile, blood glucose markers, and blood pressure in developing countries, the current study was conducted to investigate this association in apparently obese individuals.

Method and material:

Three hundred forty-seven obese adults were recruited in the present cross-sectional study. A validated 147-food item semi-quantitative food frequency questionnaire (FFQ) was used to evaluate the usual dietary intake of study participants. Dietary GI was calculated using the international GI database. Fatty acid desaturase (FADs)2 gene variants were determined according to polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). ANOVA was used to compare study variables across different tertile of GI.

Results:

We found significant differences in terms of anthropometric parameters [weight (P = 0.038), waist circumference (WC) (P = 0.023), weight to hip ratio (WHR) (P = 0.007), and fat-free mass (FFM) (P < 0.001)] between different tertiles of GI. Similarly, energy and macronutrient intakes had a significant difference across dietary GI, and subjects with a higher dietary intake of energy and macronutrients (carbohydrate, protein, and total fat) were assigned to the third tertile of dietary GI (P < 0.001). While there was no significant difference in terms of cardio-metabolic risk factors in different dietary GI tertiles. Moreover, the total GI score was non-significantly higher in the TT genotype of FADS2 gene polymorphism compared with other genotypes. While no significant difference was observed between FADS2 genotype frequencies in different GI tertiles.

Conclusion:

Calculated dietary GI was associated with several cardio-metabolic risk factors in obese individuals. However, further prospective studies and clinical trials are needed to confirm our findings.

Mouse feeding study and microbiome analysis of sourdough bread for evaluation of its health effects

Sourdough bread fermented with yeast and lactic acid bacteria (LAB) is thought to have various beneficial health effects. However, its beneficial effects were not fully evaluated with in vivo mouse model. To evaluate these effects in vivo, a mouse feeding study and microbiome analysis of white bread containing 40% sourdough (WBS) and yeast-leavened white bread (WB) were performed. Although feed consumption and body weight increased with WBS, the glycemic index was reduced, suggesting a diabetes-lowering effect, probably due to the presence of dietary fiber and short-chain fatty acids (SCFA). In addition, a mineral absorption test showed that WBS increased magnesium absorption owing to phytate degradation during fermentation. Interestingly, WBS decreased total cholesterol and triglycerides, probably due to the dietary fiber and SCFA in LAB. In addition, the ratio of low- and high-density lipoprotein was decreased in WBS, implying potential risk reduction for cardiovascular disease. An immunomodulatory assay of WBS revealed that pro-inflammatory cytokines TNF-α and IL-6 were decreased, suggesting anti-inflammatory activity. Gluten degradation by fermentation and antioxidation activity of menaquinol/ubiquinol by gut microbiota also supported the anti-inflammatory activity of sourdough bread. Furthermore, some beneficial gut bacteria, including Akkermansia, Bifidobacterium, and Lactobacillus, were increased in WBS. In particular, Akkermansia has been associated with anti-inflammatory properties. Consequently, WBS has beneficial effects on health, including decreased glycemic index and cholesterol, increased mineral availability and absorption, anti-inflammatory properties, and establishment of healthy gut microbiota.

Revisiting the therapeutic potential of tocotrienol

The therapeutic potential of the tocotrienol group stems from its nutraceutical properties as a dietary supplement. It is largely considered to be safe when consumed at low doses for attenuating pathophysiology as shown by animal models, in vitro assays, and ongoing human trials. Medical researchers and the allied sciences have experimented with tocotrienols for many decades, but its therapeutic potential was limited to adjuvant or concurrent treatment regimens. Recent studies have focused on targeted drug delivery by enhancing the bioavailability through carriers, self-sustained emulsions, nanoparticles, and ethosomes. Epigenetic modulation and computer remodeling are other means that will help increase chemosensitivity. This review will focus on the systemic intracellular anti-cancer, antioxidant, and anti-inflammatory mechanisms that are stimulated and/or regulated by tocotrienols while highlighting its potent therapeutic properties in a diverse group of clinical diseases.

Associations between Dietary Glycemic Index and Glycemic Load Values and Cardiometabolic Risk Factors in Adults: Findings from the China Health and Nutrition Survey

Studies investigating the associations between dietary glycemic index (GI) and glycemic load (GL) values and cardiometabolic risk factors (CMRF) among Chinese populations are strikingly limited. To assess the associations between dietary GI and GL values and CMRF, including dyslipidemia, hyperglycemia, and hyperuricemia in Chinese adults, we extracted data of 7886 apparently healthy adults from the 2009 wave of the China Health and Nutrition Survey. Dietary GI and GL values were calculated using data collected from three consecutive 24 h dietary recalls. Fasting lipid, glucose, and uric acid concentrations were measured and CMRF were defined on the basis of established criteria. There were no significant associations between dietary GI values and CMRF, and analyzing the data by age, sex, body mass index (BMI), and region did not alter these results. Dietary GL values were positively associated with prevalence of hyperuricemia in all participants (Q4 compared with Q1: odds ratio (OR) = 1.46; 95% CI: 1.14, 1.87; p-trend = 0.0030) and prevalence of hypercholesterolemia in participants ≥ 60 years old (Q5 compared with Q1: OR = 1.72; 95% CI: 1.11, 2.68; p-trend < 0.0010). Higher dietary GL but not GI values were associated with increased prevalence of hyperuricemia in apparently healthy Chinese adults and hypercholesterolemia in older Chinese adults. Further studies are required to confirm the public health implication of these findings.

Factors associated with dietary glycemic index and glycemic load in pregnant women and risk for gestational diabetes mellitus

The risk of gestational diabetes mellitus (GDM) increases during the second trimester of pregnancy. However, the role of dietary glycemic index (GI) and glycemic load (GL) on GDM risk is controversial. We aimed to determine the association of established risk factors of GDM with GI and GL among healthy pregnant women, and whether GI and GL were subsequently related to GDM risk. Dietary GI and GL were assessed in healthy pregnant women from the Seremban Cohort Study using a food frequency questionnaire. After adjusting for energy intake, high GI was significantly associated with lower household income, shorter stature, higher proportion of carbohydrate intake, lower sugar proportion and lower fibre intake. High GL was significantly associated with younger maternal age, higher carbohydrate proportion and lower fibre intake. GI and GL intakes were not significantly associated with GDM risk. However, they were associated with a few established risk factors of GDM.

Dietary patterns in relation to lipid profiles among Iranian adults

Introduction: Lipid metabolism is one of the main concerns of cardiovascular disease and atherosclerosis. Little is known about the association between dietary patterns and dyslipidemia. Therefore, the present study aimed to determine such association among Iranian adults. Methods: This cross-sectional study was conducted on 1433 Iranian adults in Isfahan Healthy Heart Program (IHHP). Usual dietary intakes were assessed with the use of a 48 items food frequency questionnaire (FFQ). Factor analysis was used to identify dietary patterns. Three major dietary patterns were identified: western, semi healthy and healthy fat patterns. Results: After adjustment, subjects in the upper quartiles of western dietary pattern were more likely to have high total cholesterol concentrations than those in the first quartile (odds ratio [OR]: 2.07; 95% CI: 1.25-3.42). Individuals with greater adherence to western dietary pattern had greater odds of having high low-density lipoprotein-cholesterol (LDL-C) levels compared with those in the lowest quartiles (2.53; 1.45-4.40). Conclusion: Semi healthy dietary pattern was not associated with cardiovascular disease (CVD) risk factors. Same trend was observed for healthy fat dietary pattern. Significant association was found between western dietary pattern and dyslipidemia among Iranian adults.

Association between dietary glycemic index and liver enzymes level among apparently healthy adults

OBJECTIVE

The previous studies have revealed that there is a link between dietary glycemic index and lipid profile in overweight and obesity. The aim of study was to investigate whether the glycemic index is associated with liver enzymes.

METHOD

Anthropometric and biochemical parameters were measured in 265 participants. Dietary glycemic index (GI) was assessed by using a validated food-frequency questionnaire. With adjusting confounder variable, Binary logistic regression was also used to predict the relationship between liver enzymes and quartile of intake.

RESULTS

There was a significant difference between low and high GI diet for BMR (P = 0.01), FFM (P = 0.03), TG (P = 0.02), HDL (P = 0.002). The association between HDL and glycemic index remained significant after adjustment of sex and age (P = 0.03). Using the regression model following adjustment revealed that for each 1% increase in the degree of the GI, there was 11% elevation in liver enzyme abnormalities. In both groups of men and women, enzyme abnormalities positively correlated with GI, while only men showed remarkable correlation in all models (crude model: β = 0.07, OR = 1.07, CI = 0.98to 1.16). Additionally, an increase in the degree of GI caused an elevation in enzyme abnormalities by 7%. With adjusting sex, age, BMI, and Physical activity, a significance correlation was found between GI and Enzyme abnormalities (p-value = 0.03, OR = 1.115).

CONCLUSION

Our study indicated that high glycemic index diet led to the elevated levels of the liver enzymes, while being significant only in men.

Examining sex differences in glycemic index knowledge and intake among individuals with type 2 diabetes

AIM

We examined self-reported dietary behaviours and actual food intakes among adult men and women with type 2 diabetes participating in Alberta's Caring for Diabetes (ABCD) Study.

METHODS

Participants completed 3-day food records and questions about glycemic index (GI) concept knowledge and dietary behaviours. Daily average GI and glycemic load (GL) were calculated for all carbohydrates consumed. Dietary intake was analyzed using ESHA FoodPro (version 10.13.1). Sex differences in nutrient intakes were explored across categories of GI knowledge and dietary practices.

RESULTS

Participants (N=170) mean (SD) age 65.8 (9.6) years were 46.5% women, 90.6% Caucasian with a mean BMI of 31.3 (7.0)kg/m² and diabetes duration of 13.4 (8.6) years. Overall, 60% of men versus 40% of women consumed carbohydrates in quantities below Acceptable Macronutrient Distribution Ranges (AMDR). About 80% of men versus 90% of women consumed proteins above AMDR whereas 60% versus 65% of women consumed fats above AMDR. Fibre intake among men was lower than recommended (p<0.01). Men who reported having knowledge of the GI-concept also reported lower GI intake versus men who did not (p=0.03).

CONCLUSION

Sex differences exist in low-GI diabetes self-care dietary behaviours among adults with type 2 diabetes participating in this study. Gender-sensitive approaches for enhancing diabetes self-care low-GI dietary behaviour should be explored.

Glycemic load and coronary heart disease in a Mediterranean population: the EPIC Greek cohort study

BACKGROUND AND AIMS

High glycemic load (GL) has been associated with increased coronary heart disease (CHD) risk. We evaluated whether preference of low-GL foods conveys incremental benefits with respect to CHD, especially to people adhering to the traditional Mediterranean diet (MD).

METHODS AND RESULTS

We analyzed data from the Greek European Prospective Investigation into Cancer and Nutrition, including 20,275 participants free of cardiovascular diseases, cancer, or diabetes at baseline and without incident diabetes. Subjects completed a validated, semi-quantitative food frequency questionnaire at enrollment. We calculated a 10-point MD adherence score and the dietary GL, and estimated hazard ratios (HRs) for CHD incidence and mortality through Cox proportional hazard regression. After a median follow-up of 10.4 years, 417 participants developed CHD, and 162 died from the disease. A significant positive association of GL with CHD incidence emerged (HR for the highest versus the lowest tertile = 1.41, 95% confidence interval, CI: 1.05-1.90). HRs for CHD mortality exceeded unity but were not statistically significant. The association with GL was stronger among subjects with higher body mass index. High adherence to MD with low/moderate GL was associated with lower risk of CHD incidence (HR = 0.61, CI: 0.39-0.95) and mortality (HR = 0.47, 95% CI: 0.23-96).

CONCLUSION

High dietary GL increases the risk of CHD. Compared to a high GL diet with suboptimal adherence to the traditional Mediterranean pattern, a low/moderate GL diet that also conforms to the traditional MD principles could lead to a 40% reduced risk for CHD, and over 50% reduced risk for death from CHD.

Metabolic syndrome related health inequalities in Korean elderly: Korean National Health and Nutrition Examination Survey (KNHAES)

While the prevalence of metabolic syndrome is increasing, little is presently known about this syndrome in Korean elderly. This study aimed to group metabolic risk factors and to examine the associations between groups of health living conditions and metabolic syndrome using data from the Korean National Health Examination and Nutritional Assessment (KNHANES). A total of 1,435 subjects aged over 65 years old with both biochemical and dietary data information were obtained from the 4th and 5th KNHANES (2007–2012). Using stratified and multistage probability sample data, five components of metabolic syndrome were adopted to identify health inequalities. Our findings show that groups of health living conditions such as dietary pattern, body image, muscle mass, and fat mass were differentially associated with metabolic syndrome risk factors. Future studies are necessary to examine the underlying mechanisms of individual health living conditions to better understand the role of metabolic risk factors in metabolic syndrome in elderly.

Mediterranean diet pyramid: a proposal for Italian people

Bread was a staple in the traditional Mediterranean diet of the early 1960s, as well as nowadays; however, it was a stone ground sourdough bread in Nicotera and probably in the Greek cohorts of the Seven Countries Study. In the present review, the nutritional characteristics of this food are analyzed in relation to its protective effects on coronary heart disease, metabolic diseases and cancer. According to our traditions, cultural heritage and scientific evidence, we propose that only cereal foods with low glycemic index (GI) and rich in fiber have to be placed at the base of the Mediterranean diet pyramid, whereas refined grains and high GI starchy foods have to be sited at the top.

Effects of Carbohydrate and Dietary Fiber Intake, Glycemic Index and Glycemic Load on HDL Metabolism in Asian Populations

High-density lipoprotein (HDL) is a lipoprotein which has anti-atherogenic property by reverse cholesterol transport from the peripheral tissues to liver. Low HDL-cholesterol (HDL-C) levels are associated with the development of coronary artery diseases (CADs). Various epidemiological studies have suggested that the development of CAD increase in individuals with less than 40 mg/dL of HDL-C. In spite of accumulation of evidences which suggest a significant association between low HDL-C and cardiovascular diseases, effects of dietary factors on HDL metabolism remained largely unknown. There may be interracial differences in effects of dietary factors on HDL metabolism. Here we reviewed published articles about effects of carbohydrate and dietary fiber intake, glycemic index (GI) and glycemic load (GL), on HDL-C metabolism, regarding meta-analyses and clinical studies performed in Asian population as important articles. Low carbohydrate intake, GI and GL may be beneficially associated with HDL metabolism. Dietary fiber intake may be favorably associated with HDL metabolism in Asian populations.

The influence of fasting insulin level in post-gestational diabetes mellitus women receiving low-glycaemic-index diets

Post-gestational diabetes mellitus (GDM) women are recommended weight loss to manage increased cardio-metabolic risks. We investigated the effects of lowering diet glycaemic index (GI) on fasting blood glucose (FBG), serum lipids, body weight and composition of post-GDM women with varying fasting insulin levels (INS). Seventy-seven Asian, non-diabetic women with previous GDM (aged 20–40 years, mean BMI: 26.4±4.6 kg m⁻²) were recruited. At baseline, 20 subjects with INS <2 μIU ml⁻¹ and 18 with INS ⩾2 μIU ml⁻¹ received conventional dietary recommendations (CHDR) only. CHDR emphasised energy and fat intake restriction and encouraged increase in dietary fibre intakes. Twenty-four subjects with INS <2 μIU ml⁻¹ and 15 with INS ⩾2 μIU ml⁻¹, in addition to CHDR, received low-GI education (LGI). Changes in FBG, serum lipids, body weight and body composition were evaluated. Subjects with INS <2 μIU ml⁻¹ had similar outcomes with both diets. After 1 year, subjects with INS ⩾2 μIU ml⁻¹ who received LGI education had reductions in FBG and triglycerides. Subjects who received CHDR observed increase in both FBG and triglycerides (P<0.05). Among all subjects, diet GI was lower and dietary fibre intakes were higher in LGI compared with CHDR subjects (all P<0.05). Thus, in Asian post-GDM women with normal/higher INS, adding low-GI education to CHDR improved management of FBG and triglycerides.

Genotype by environment interaction effects on starch content and digestibility in potato (Solanum tuberosum L.)

Biochemically, starch is composed of amylose and amylopectin but can also be defined by its digestibility rates within the human intestinal tract, i.e., rapidly digested (RDS), slowly digested (SDS), or resistant (RS). The relative ratio of these starch components is the main contributor to differences in the glycemic index (GI) of carbohydrate sources. This study evaluated the digestible starch profile of 12 potato genotypes comprising elite breeding lines and commercial varieties in six environments, with the optimal profile defined as low RDS and high SDS. Genotype by environment interaction (GEI) analysis found significant (p = 0.05) genotypic and environmental effects for all digestibility rate components; however, interaction effects were only significant for SDS. Optimal starch profiles were identified for two genotypes, CV96044-3 and Goldrush. The desirable starch profile in these potato cultivars can be exploited in breeding programs for the improvement of starch profile and other important characteristics such as high yields and disease resistance.

Use of the glycemic index in nutrition education

Recently, the lack of studies providing practical guidance for the use of the glycemic index has been indicated as the cause of its little use in nutrition education. The aim of this study is to give instructions on the use of the glycemic index as a tool to be used in nutrition education to estimulate the consumption of low glycemic index foods. Studies published over the past 12 years, in addition to classic studies on this topic, found in the databases MedLine, ScienceDirect, SciELO and Lilacs exploring the importance of the glycemic index and the factors that affect the glycemic index were selected for this article. The preparation of lists grouping foods according to their glycemic index should be based on information found in tables and specific web sites. This is an interesting strategy that must be very carefully conducted, considering the eating habits of the assisted people. To reduce the postprandial blood glucose response, high glycemic index foods should be consumed in association with the following foods: high protein and low fat foods, good quality oils and unprocessed foods with high fiber content. Caffeine should also be avoided. The glycemic index should be considered as an additional carbohydrate-selection tool, which should be part of a nutritionally balanced diet capable of promoting and/or maintaining body weight and health.

Optimal energy distribution of carbohydrate intake for Japanese elderly patients with type 2 diabetes: the Japanese Elderly Intervention Trial

AIM

In diet therapy for diabetes, optimal energy intake and the energy distribution of macronutrients (protein : fat : carbohydrate [PFC] energy ratio) are important. We aimed to clarify the correlation between the PFC energy ratio and metabolic parameters including glycated hemoglobin A1c (HbA1c) and triglycerides in Japanese elderly patients with type 2 diabetes mellitus aged 65 years or older.

METHODS

Participants were 1173 diabetic patients aged 65 years or older with serum HbA1c level of >/=7.4% enrolled in the Japanese Elderly Diabetes Intervention Trial (J-EDIT). The participants were divided into four groups by the percentage of total energy intake (%E) of carbohydrate (C1: less than 55%E, C2: 55%E or more and less than 60%E, C3: 60%E or more and less than 65%E, and C4: 65%E or more). Relations of %E of carbohydrate to HbA1c and other metabolic parameters, energy intake and nutritional intake were examined. Furthermore, the subjects were divided into four categories by HbA1c levels by quartile method (Q1: less than 7.90%, Q2: 7.90% or more and less than 8.30%, Q3: 8.30% or more and less than 8.80%, Q4: 8.80% or more). Relations of HbA1c to other metabolic parameters, energy intake and nutritional intake were examined.

RESULTS

The mean HbA1c levels in the four groups were C1: 8.40%, C2: 8.50%, C3: 8.41% and C4: 8.36% in men, and C1: 8.51%, C2: 8.47%, C3: 8.35% and C4: 8.52% in women, respectively. There were no significant differences and linear trend in HbA1c levels across groups. The mean triglyceride levels were in the range of 122-128 mg/dL in men from C1 to C3, although it was significantly higher in C4 (177 mg/dL). The mean triglyceride levels were in the range of 128-136 mg/dL in women from C1 to C3, although it was significantly higher in Q4 (150 mg/dL). Amounts of protein and fat intakes decreased with an increase of %E of carbohydrate, although amount of carbohydrate intake did not change significantly. As a result, %E of protein and fat, and energy intake decreased in both men and women with an increase in %E of carbohydrate. Among the four quartiles divided by HbA1c levels, there were no significant differences in energy intake and PFC energy ratio.

CONCLUSIONS

The present study suggests that, within the range studied, the carbohydrate energy ratio has no correlation with HbA1c levels. However, serum triglyceride levels increased and high-density lipoprotein cholesterol levels decreased significantly, with an increase of %E of carbohydrate in men, and the same tendencies were observed in women. Furthermore, in patients with 65%E or more of carbohydrate, serum triglyceride levels exceeded 150 mg/dL, which is the recommended treatment target for diabetic patients. These results suggest that the ideal %E of carbohydrate for Japanese elderly type 2 diabetes is less than 65. The lower limit of %E of carbohydrate could not be determined from the present study.

Glycemic index and glycemic load are associated with some cardiovascular risk factors among the PREMIER study participants

BACKGROUND

The clinical significance of glycemic index (GI) and glycemic load (GL) is inconclusive.

OBJECTIVE

This study was conducted to examine the association of GI and GL with clinical cardiovascular disease (CVD) risk factors including body weight, blood pressure (BP), serum lipids, fasting glucose, insulin and homocysteine over time among the PREMIER participants.

DESIGN

PREMIER was an 18-month randomized lifestyle intervention trial, conducted from 2000 to 2002, designed to help participants reduce BP by following the Dietary Approaches to Stop Hypertension (DASH) dietary pattern, losing weight, reducing sodium and increasing physical activity. GI and GL were estimated from 24 h diet recall data at baseline, 6 and 18 months after intervention. PROC MIXED model was used to examine the association of changes in GI or GL with changes in CVD risk factors.

RESULTS

A total of 756 randomized participants, 62% females and 34% African Americans and who averaged 50.0±0.3 years old and 95.3±0.7 kg, were included in this report. Neither GI nor GL changes was associated with changes in any risk factors at 6 months. At 18 months, however, the GI change was significantly and positively associated with total cholesterol (TC) change only (p<0.05, β=23.80±12.11 mg/dL or 0.62±0.31 mmol/L) with a significant age interaction. The GL change was significantly associated with TC (p=0.02, β=0.28±0.15 mg/dL or 0.01±0.00 mmol/L) positively and with low density lipoprotein cholesterol (LDL-C) changes negatively (p=0.03, β=-0.01±0.00 mg/dL or -0.00±0.00 mmol/L), and significant age interactions were observed for both.

CONCLUSIONS

GI and GL was associated with TC and LDL-C after controlling for energy, fat and fiber intake and other potential confounders and the associations were modified by age. Further investigation into this relationship is important because of its potential clinical impact.

Potato consumption and cardiovascular disease risk factors among Iranian population

BACKGROUND

Previous studies investigated the effects of dietary glycaemic index and glycaemic load on cardiovascular risk factors. Little evidence is available regarding the association between potato intake and cardiovascular risk factors in Iran.

OBJECTIVE

This cross-sectional study was conducted in the first stage of Isfahan Healthy Heart Programme.

METHODS

A total of 4774 subjects were included in the present study. Dietary intake was assessed with a 49-item food frequency questionnaire. Biochemical assessments were done according to the standard protocol.

RESULTS

There were significant associations between potato consumption and diabetes mellitus (odds ratio (OR): 1.38; 95% CI: 1.14-1.67; p < 0.001), high fasting blood sugar level (OR: 1.40; 95% CI: 1.17-1.68; p < 0.001) and low serum high density lipoprotein level (OR: 1.10; 95% CI: 1.01-1.20; p = 0.02) remained after adjustments for possible confounding factors.

CONCLUSION

We found a positive relation between potato consumption, high fasting blood glucose level and diabetes mellitus.

Wholegrain oat-based cereals have prebiotic potential and low glycaemic index

Population studies show a positive association between increased dietary intake of wholegrains and reduced risk of cardiometabolic disorders. Consumption of wholegrain food has been associated with lower blood glucose and therefore may contribute to a low-glycaemic load diet. The ability to mediate a prebiotic modulation of gut microbiota has recently been suggested to have an inverse correlation with risk of cardiometabolic disease. To date very little work has been carried out on the functionality of wholegrain breakfast cereals in terms of glycaemic response or impact on gut microbiota. An investigation into identifying wholegrain-based breakfast cereals demonstrating both low glycaemic index (GI) and prebiotic attributes was performed. Afterin vitrodigestion, cereal samples were supplemented to pH-controlled anaerobic batch cultures of the human faecal microbiota. Total bacteria populations increased significantly (P < 0·05) in all treated cultures, and the fermentation of a wholegrain oat cluster cereal was associated with proliferation of theBifidobacteriumgenus (P = 0·02). Smaller, but significant increases in theBifidobacteriumgenus were observed for a further four oat-based cereals. Significant increases in theLactobacillus–Enterococcusgroup were observed for granola (P = 0·01), 100 % wholegrain aggregate (P = 0·04) and 70 % wholegrain loops (P = 0·01). Cereals demonstrating prebiotic potential were selected for GI determination in twelve healthy subjects. The wholegrain oat aggregate cereal achieved the lowest GI value (40), three other cereals ranged between 44 and 74, with instant porridge resulting in a GI value similar to the standard glucose control. The present study suggests that wholegrain oat-based breakfast cereals may be prebiotics and have the potential to have low GI.

Food intake and dietary glycaemic index in free-living adults with and without type 2 diabetes mellitus

A recent Cochrane review concluded that low glycaemic index (GI) diets are beneficial in glycaemic control for patients with type 2 diabetes mellitus (T2DM). There are limited UK data regarding the dietary GI in free-living adults with and without T2DM. We measured the energy and macronutrient intake and the dietary GI in a group (n = 19) of individuals with diet controlled T2DM and a group (n = 19) without diabetes, matched for age, BMI and gender. Subjects completed a three-day weighed dietary record. Patients with T2DM consumed more daily portions of wholegrains (2.3 vs. 1.1, P = 0.003), more dietary fibre (32.1 vs. 20.9 g, P < 0.001) and had a lower diet GI (53.5 vs. 57.7, P = 0.009) than subjects without T2DM. Both groups had elevated fat and salt intake and low fruit and vegetable intake, relative to current UK recommendations.

CONCLUSIONS

Patients with T2DM may already consume a lower GI diet than the general population but further efforts are needed to reduce dietary GI and achieve other nutrient targets.

An extract from brown rice inhibits signal transduction of angiotensin II in vascular smooth muscle cells

BACKGROUND

Health benefits of brown rice over white rice have been described previously. However, whether the outer bran of rice contains an ingredient useful to prevent cardiovascular diseases remains unknown. The subaleurone layer of rice, which is usually lost by milling brown rice for whitening, is rich in varied nutrients, suggesting that some ingredient contained within this layer may be beneficial for the cardiovascular system.

METHODS

To assess potential benefits of the subaleurone layer toward pathological vascular remodeling, we examined the effects of the layer extracts from Japanese rice (Oryza sativa var. japonica) on angiotensin II (Ang II)-induced signal transduction and hypertrophy in cultured rat vascular smooth muscle cells (VSMCs).

RESULTS

Pretreatment of the ethyl acetate extract (100 µg/ml), but not other extracts, inhibited Ang II (100 nmol/l)-induced immediate signal transduction events. Also, the extract diminished c-Fos expression and hypertrophic protein accumulation induced by Ang II in the cells.

CONCLUSION

These data suggest that an ingredient in the ethyl acetate extract from the subaleurone layer of rice has a protective effect toward cardiovascular diseases by interfering with signal transduction induced by Ang II.

Dietary glycemic index, glycemic load, and intake of carbohydrate and rice in relation to risk of mortality from stroke and its subtypes in Japanese men and women

We assessed the relationship of the dietary glycemic index (GI), glycemic load (GL), and intake of carbohydrate and rice, and risk of mortality from stroke and its subtypes. The cohort consisted of 12,561 men and 15,301 women residing in Takayama, Japan, in 1992. At the baseline, a food frequency questionnaire was administered; and the dietary GI, GL, and intake of carbohydrates and rice were estimated. Deaths from stroke occurring in the cohort were prospectively noted until 1999 with data from the office of the National Vital Statistics. The risk of mortality from stroke was assessed with a Cox proportional hazard model after adjusting for age; body mass index; smoking status; physical activity; history of hypertension; education; and intake of total energy, alcohol, dietary fiber, salt, and total fat. The risk of stroke subtypes was assessed in the age-adjusted model. The hazard ratios of total stroke comparing the highest vs the lowest quartiles of the dietary GI were 0.78 (95% confidence interval [CI], 0.41-1.47) with P(trend) = .50 in men and 2.09 (95% CI, 1.01-4.31) with P(trend) = .10 in women. Among women, the association was also significant with the risk of ischemic stroke (hazard ratio = 2.45; 95% CI, 1.01-5.92; P(trend) = .03); and a significant positive trend was also observed between dietary GL and mortality from hemorrhagic stroke (P(trend) = .05). The current study implies that diets with a high dietary GI increase the risk of mortality from stroke among Japanese women.

A high legume low glycemic index diet improves serum lipid profiles in men

Clinical studies have shown that fiber consumption facilitates weight loss and improves lipid profiles; however, the beneficial effects of high fermentable fiber low glycemic index (GI) diets under conditions of weight maintenance are unclear. In the Legume Inflammation Feeding Experiment, a randomized controlled cross-over feeding study, 64 middle-aged men who had undergone colonoscopies within the previous 2 years received both a healthy American (HA) diet (no legume consumption, fiber consumption = 9 g/1,000 kcal, and GI = 69) and a legume enriched (1.5 servings/1,000 kcal), high fiber (21 g/1,000 kcal), low GI (GI = 38) diet (LG) in random order. Diets were isocaloric and controlled for macronutrients including saturated fat; they were consumed each for 4 weeks with a 2-4 week break separating dietary treatments. Compared to the HA diet, the LG diet led to greater declines in both fasting serum total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) (P < 0.001 and P < 0.01, respectively). Insulin-resistant (IR) subjects had greater reductions in high density lipoprotein cholesterol (HDL-C; P < 0.01), and triglycerides (TAG)/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. Insulin-sensitive (IS) subjects had greater reductions in TC (P < 0.001), LDL-C (P < 0.01), TC/HDL-C (P < 0.01), and LDL-C/HDL-C (P = 0.02) after the LG diet, compared to the HA diet. In conclusion, a high legume, high fiber, low GI diet improves serum lipid profiles in men, compared to a healthy American diet. However, IR individuals do not achieve the full benefits of the same diet on cardiovascular disease (CVD) lipid risk factors.

Consumption of a high glycemic index diet increases abdominal adiposity but does not influence adipose tissue pro-oxidant and antioxidant gene expression in C57BL/6 mice

The hypothesis of this study is that consumption of a high glycemic index (GI) starch will increase adiposity, increase expression of the pro-oxidant enzyme (nicotinamide adenine dinucleotide phosphate [NADPH] oxidase), and decrease expression of the antioxidant enzymes (catalase, glutathione peroxidase [GPx], and superoxide dismutase [SOD]) in adipose tissue of mice. C57BL/6 mice (n = 5-8/group) were fed a diet containing either high-GI starch (100% amylopectin) or low-GI starch (60% amylose/40% amylopectin) under low-fat (LF) or high-fat (HF) conditions for 16 weeks. Meal tolerance tests (MTTs) indicated that the postprandial blood glucose response over 120 minutes for the high-GI mice under LF and HF conditions was significantly greater than for mice fed low-GI diets. This result was not due to increased food consumption by the high-GI mice during the MTT. Although there was no difference in body weight between mice fed high-GI or low-GI starch, LF high-GI mice had significantly greater adiposity compared to LF low-GI mice. High-fat mice had a significant increase in NADPH oxidase expression compared to LF mice, but there was no significant effect of starch on NADPH oxidase expression. High-fat diet significantly decreased the expression of GPx and catalase, but there was no significant effect of starch on GPx and catalase expression. There was no difference in SOD expression among any of the diet groups. In conclusion, high GI diets increase adiposity under LF conditions but do not influence pro-oxidant or antioxidant enzyme gene expression in adipose tissue of C57BL/6 mice.

Dietary glycemic index, glycemic load and blood lipid levels in middle-aged Japanese men and women

AIMS

This study investigated the association between dietary glycemic index (GI)/glycemic load (GL) and serum lipids in middle-aged Japanese men and women.

METHODS

The study participants were employees of a metal products factory in Japan: 2,257 men and 1,598 women aged 35 years or older. Dietary GI and GL were assessed using a self-administered diet history questionnaire. Serum lipid levels, adjusted for age, body mass index, alcohol consumption, smoking, physical activity, menopause status, and dietary intake of total energy, saturated fatty acids, monounsaturated fatty acids, polyunsaturated fatty acids, cholesterol and fiber, were compared among GI/GL quintiles for each gender.

RESULTS

No significant associations were observed between GI and adjusted serum lipids in men or women. In contrast, GL was inversely associated with HDL-cholesterol in men and women (p for trend=0.001 for men and < 0.001 for women), and positively associated with non-HDL-cholesterol (p for trend=0.010), LDL-cholesterol (p for trend=0.035) and triglycerides (p for trend=0.011) in women; however, alcohol drinking affected these associations; there was no association between GL and serum lipids in male nondrinkers and between GL and LDL-cholesterol in female nondrinkers.

CONCLUSION

GL was inversely associated with HDL-cholesterol and positively associated with non-HDL-cholesterol in Japanese women. These associations in men were not observed in nondrinkers. A high-GL diet for women may have an atherogenic effect through these serum lipid abnormalities.

Novel findings on the metabolic effects of the low glycaemic carbohydrate isomaltulose (Palatinose)

The slow digestible disaccharide isomaltulose (iso; Palatinose) is available as novel functional carbohydrate ingredient for manufacturing of low glycaemic foods and beverages. Although basically characterised, various information on physiological effects of iso are still lacking. Thus, the objective of the present study was to expand scientific knowledge of physiological characteristics of iso by a set of three human intervention trials. Using an ileostomy model, iso was found to be essentially absorbed, irrespective of the nature of food (beverage and solid food). Apparent digestibility of 50 g iso from two different meals was 95.5 and 98.8 %; apparent absorption was 93.6 and 96.1 %, respectively. In healthy volunteers, a single dose intake of iso resulted in lower postprandial blood glucose and insulin responses than did sucrose (suc), while showing prolonged blood glucose delivery over 3 h test. In a 4-week trial with hyperlipidaemic individuals, regular consumption of 50 g/d iso within a Western-type diet was well tolerated and did not affect blood lipids. Fasting blood glucose and insulin resistance were lower after the 4-week iso intervention compared with baseline. This would be consistent with possible beneficial metabolic effects as a consequence of the lower and prolonged glycaemic response and lower insulinaemic burden. However, there was no significant difference at 4 weeks after iso compared with suc. In conclusion, the study shows that iso is completely available from the small intestine, irrespective of food matrix, leading to a prolonged delivery of blood glucose. Regular iso consumption is well tolerated also in subjects with increased risk for vascular diseases.

Dietary glycemic index, dietary glycemic load, blood lipids, and coronary heart disease

Objective. To examine the associations of dietary glycemic index (GI) and dietary glycemic load (GL) with blood lipid concentrations and coronary heart disease (CHD) in nondiabetic participants in the Health Worker Cohort Study (HWCS). Materials and Methods. A cross-sectional analysis was performed, using data from adults who participated in the HWCS baseline assessment. We collected information on participants' socio-demographic conditions, dietary patterns and physical activity via self-administered questionnaires. Dietary GI and dietary GL were measured using a validated food frequency questionnaire. Anthropometric and clinical measurements were assessed with standardized procedures. CHD risk was estimated according to the sex-specific Framingham prediction algorithms. Results. IIn the 5,830 individuals aged 20 to 70 who were evaluated, dietary GI and GL were significantly associated with HDL-C, LDL-C, LDL-C/HDL-C ratio, and triglycerides serum levels. Subjects with high dietary GI have a relative risk of 1.56 (CI 95%; 1.13-2.14), and those with high dietary GL have a relative risk of 2.64 (CI 95%; 1.15-6.58) of having an elevated CHD risk than those who had low dietary GI and GL. Conclusions. Our results suggest that high dietary GI and dietary GL could have an unfavorable effect on serum lipid levels, which are in turn associated with a higher CHD risk.

Association of glycemic load with cardiovascular disease risk factors: the Women's Health Initiative Observational Study

OBJECTIVE

Associations between dietary glycemic load (GL) and cardiovascular disease risk factors, including plasma lipoprotein/lipid levels, blood pressure, and glucose metabolism factors, in the Women's Health Initiative Observational Study were examined.

METHODS

A random sample of 878 Observational Study participants (postmenopausal women 50-79 y of age) with baseline blood measurements (647 white, 104 black, 127 Hispanic) was included. Dietary GL was estimated from baseline food-frequency questionnaires, which assessed dietary intake over the previous 3 mo. At the baseline visit, participants completed demographic and health habit questionnaires, fasting blood samples were collected, anthropometric measurements were completed, and blood pressure was assessed.

RESULTS

In all participants combined, GL was inversely associated with high-density lipoprotein cholesterol (P for trend = 0.004) and positively associated with log(10)-transformed triacylglycerols (P = 0.008). Although there were no statistically significant interactions of race/ethnicity with associations between GL and cardiovascular disease risk factors, stratified results were suggestive, showing that GL was positively associated with total cholesterol (P = 0.018) and low-density lipoprotein cholesterol (P = 0.038) in Hispanics. In white subjects, there was a trend of reduced high-density lipoprotein cholesterol with higher GL (P = 0.003), whereas GL was positively associated with log(10)-transformed triacylglycerols (P = 0.015). Associations between GL and high-density lipoprotein cholesterol and between GL and triacylglycerols also differed by body mass index, although the interactions were not statistically significant.

CONCLUSION

Among these generally healthy postmenopausal women, GL was associated with high-density lipoprotein cholesterol and triacylglycerols. Suggestive effects of race/ethnicity and body mass index on these associations need to be confirmed in larger studies.

Fructose consumption: considerations for future research on its effects on adipose distribution, lipid metabolism, and insulin sensitivity in humans

Results from a recent study investigating the metabolic effects of consuming fructose-sweetened beverages at 25% of energy requirements for 10 wk demonstrate that a high-fructose diet induces dyslipidemia, decreases insulin sensitivity, and increases visceral adiposity. The purpose of this review is to present aspects of the study design which may be critical for assessment of the metabolic effects of sugar consumption. Collection of postprandial blood samples is required to document the full effects of fructose on lipid metabolism. Fasting triglyceride (TG) concentrations are an unreliable index of fructose-induced dyslipidemia. Differences in the short-term (24-h) and long-term (>2 wk) effects of fructose consumption on TG and apolipoprotein-B demonstrate that acute effects can differ substantially from those occurring after sustained fructose exposure. Investigating the effects of fructose when consumed ad libitum compared with energy-balanced diets suggest that additive effects of fructose-induced de novo lipogenesis and positive energy balance may contribute to dyslipidemia and decreased insulin sensitivity. Increases of intra-abdominal fat observed in subjects consuming fructose, but not glucose, for 10 wk indicate that the 2 sugars have differential effects on regional adipose deposition. However, the increase of fasting glucose, insulin, and homeostasis model assessment-insulin resistance at 2 wk and the lack of increase of 24-h systemic FFA concentrations suggest that fructose decreases insulin sensitivity independently of visceral adiposity and FFA. The lower postprandial glucose and insulin excursions in subjects consuming fructose and increased excursions in those consuming glucose do not support a relationship between dietary glycemic index and the development of dyslipidemia, decreased insulin sensitivity, or increased visceral adiposity.

Dietary carbohydrates and cardiovascular disease risk factors in the Framingham offspring cohort

OBJECTIVE

Evidence from observational studies has suggested that carbohydrate quality rather than absolute intake is associated with greater risk of chronic diseases. The aim of this study was to examine the relationship between carbohydrate intake and dietary glycemic index and several cardiovascular disease risk factors.

METHODS

We examined cross-sectional associations between total carbohydrate and dietary glycemic index (GI) intakes and several cardiovascular disease risk factors (CVD) in a sample of 2,941 Framingham Offspring Participants. CVD risk factors included waist, blood pressure, lipids, fasting insulin, fasting glucose, and the insulin sensitivity index (ISI(0,120)). Dietary intake was assessed by a food frequency questionnaire (FFQ) and categorized by quintiles of dietary intake.

RESULTS

After adjustment for potential confounding factors, dietary GI was positively associated with fasting triglycerides (mean: 115mg/dL in the lowest and 127 mg/dL in the highest quintile of intake; P for trend < 0.001), fasting insulin (26.8 and 28.9 microu/mL, respectively, P for trend < 0.0001), and inversely associated with HDL cholesterol (49 and 47 mg/dL, respectively, P for trend 0.003) and ISI(0,120) (26.8 and 25.1, P for trend < 0.001). There was no significant relationship between dietary GI and waist circumference, total cholesterol, LDL cholesterol and fasting glucose. Intakes of total carbohydrate were inversely associated with waist circumference and HDL cholesterol, and positively associated with fasting triglycerides.

CONCLUSION

These cross-sectional findings support the hypothesis that a high GI diet unfavorably affects CVD risk factors and therefore, substitution of high with low GI dietary carbohydrates may have reduce the risk of CVD.

Should glycemic index and glycemic load be considered in dietary recommendations?

High glycemic index (GI) and glycemic load (GL) have been proposed to be associated with increased risk of lifestyle diseases. Since protein intake varies little in humans, adherence to the common recommendation to reduce fat intake probably leads to increases in carbohydrate intake, which emphasizes the need to investigate the effects of carbohydrate on diet-related conditions and diseases. This review examines the epidemiological literature linking GI and GL to heart disease, insulin sensitivity, type 2 diabetes, dyslipidemia, and obesity among initially healthy people. The evidence for associations between GI and particularly GL and health among free-living populations is mixed. Only the positive association between GI and development of type 2 diabetes was consistent across cross-sectional and longitudinal studies for both sexes. Low GI/GL may protect against heart disease in women, and cross-sectional studies indicate low GI/GL may reduce high-density-lipoprotein cholesterol and triacylglycerol levels in both sexes. Based on the evidence found in this review, it seems premature to include GI/GL in dietary recommendations.

Índice glicêmico: uma abordagem crítica acerca de sua utilização na prevenção e no tratamento de fatores de risco cardiovasculares

As doenças cardiovasculares são consideradas um grande problema de saúde pública, uma vez que são a principal causa de morte no Brasil e no mundo. Essas doenças possuem etiologia multifatorial. Além da susceptibilidade genética, outros fatores, tais como idade e presença de hipertensão arterial, dislipidemias, obesidade, diabetes mellitus, inatividade física e alguns hábitos alimentares inadequados, são considerados importantes fatores de risco para o desenvolvimento de doenças cardiovasculares. O elevado consumo de carboidratos tem sido associado ao aumento da obesidade, às dislipidemias, à intolerância à glicose/diabetes mellitus e à resistência insulínica, estando, dessa forma, entre os fatores de risco das doenças cardiovasculares. Entretanto, existem controvérsias acerca da influência da qualidade do carboidrato ingerido no desenvolvimento de tais doenças, independentemente da quantidade ingerida. O índice glicêmico é um indicador da qualidade do carboidrato ingerido. Sua utilidade em condições de vida livre tem sido questionada, devido à interferência de vários fatores, os quais são difíceis de serem controlados sob tais condições. Este trabalho objetivou analisar criticamente os estudos que avaliaram o efeito do índice glicêmico dos alimentos na manifestação de doenças cardiovasculares e seus fatores de risco.

Dietary breads: myth or reality?

AIMS

To assess the differences in acute effects of whole wheat bread, wheat bran bread and rye bread--perceived as dietary (Low caloric!) breads--on glucose and insulin levels in patients with type 2 diabetes, as compared to white wheat bread.

METHODS

One hundred twenty one type 2 diabetic patients were randomized into three groups as whole wheat, wheat bran and rye bread groups. Each group ate 100 g of bread with water with in 10 min. Blood glucose measurements were made at every 30 min in 2 h. Insulin was measured at fasting and at the second hour in the patients who do not use insulin. The same processes were repeated on the following day, with white wheat bread for each group.

RESULTS

No significant difference was found in either glycemic or insulinemic effects between four types of breads when compared to each other (p=0.093 for glycemic effect and p=0.297 for insulinemic effect).

CONCLUSION

Three different bread types consumed as an alternative to white bread in Turkey, increase blood glucose levels of diabetic patients similar to white bread.

Validity of carbohydrate, glycaemic index and glycaemic load data obtained using a semi-quantitative food-frequency questionnaire

Objective

To assess the ability of a food-frequency questionnaire (FFQ) to rank Australians according to their intake of total carbohydrate, sugar, starch, fibre, glycaemic index (GI) and glycaemic load (GL).

Design

Cross-sectional sample from a population cohort.

Setting

Two postcode areas west of Sydney, Australia.

Subjects

From 1992 to 1994, a total of 2868 older Australians provided dietary data using a 145-item Willett-derived FFQ. A representative sub-sample of 78 subjects completed three 4-day weighed food records (WFRs). Pearson and Spearman correlations, Bland–Altman plots and weighted kappa values were calculated.

Results

Compared with the WFR, the FFQ provided higher mean estimates of all nutrients except starch and GI. All Pearson and/or Spearman correlations were greater than 0.5, except for GL. For GI, sugar, starch and fibre, the regression lines from the Bland–Altman analysis indicated a non-significant linear trend (P = 0.07, P = 0.36, P = 0.28 and P = 0.10, respectively). For GL and total carbohydrate, however, there was a significant linear trend (P = 0.006 and P < 0.0001, respectively), indicating that as the GL and carbohydrate intake of individuals increased, so did the magnitude of the error between the FFQ and WFR. Weighted kappa values all indicated moderate to good agreement, with the exception of GL which was only fair. The proportions of subjects correctly classified within one quintile for all of the nutrients were over 50% and gross misclassification was low (<10%).

Conclusion

This FFQ was able to rank individuals according to their intakes of total carbohydrate, sugar, starch, fibre and GI, but not as well for GL.

Reproducibility and relative validity of dietary glycaemic index and load assessed with a self-administered diet-history questionnaire in Japanese adults

Although many epidemiological studies have examined the association of dietary glycaemic index (GI) and glycaemic load (GL) with health outcomes, information on the reproducibility and relative validity of these variables estimated from dietary questionnaires is extremely limited. We examined the reproducibility and relative validity of dietary GI and GL assessed with a self-administered diet-history questionnaire (DHQ) in adult Japanese. A total of ninety-two Japanese women and ninety-two Japanese men aged 31–76 years completed the DHQ (assessing diet during the preceding month) and 4 d dietary records (DR) in each season over a 1-year period (DHQ1–4 and DR1–4, respectively) and the DHQ at 1 year after completing DHQ1 (DHQ5). We used intraclass correlations between DHQ1 and DHQ5 to assess reproducibility, and Pearson correlations between the mean of DR1–4 and mean of DHQ1–4 and between the mean of DR1–4 and DHQ1 to assess relative validity. Reproducibility correlations for dietary GI and GL were 0·57 and 0·69 among women and 0·65 and 0·58 among men, respectively. Validity correlations for dietary GI and GL assessed by DHQ1–4 were 0·72 and 0·66 among women and 0·65 and 0·71 among men, respectively. Corresponding correlations for DHQ1 were 0·53 and 0·58 among women and 0·57 and 0·60 among men, respectively. White rice was the major contributor to GI and GL in both methods (49–64 %). These data indicate reasonable reproducibility and relative validity of dietary GI and GL assessed by a DHQ for Japanese adults, whose dietary GI and GL are primarily determined by the GI of white rice.

Glycemic index and glycemic load in relation to food and nutrient intake and metabolic risk factors in a Dutch population

BACKGROUND

Previous studies on the glycemic index (GI) and glycemic load (GL) reported inconsistent findings on their association with metabolic risk factors. This may partly have been due to differences in underlying dietary patterns.

OBJECTIVE

We aimed to examine the association of GI and GL with food and nutrient intake and with metabolic risk factors including blood glucose, insulin, lipids, and high-sensitivity C-reactive protein (CRP).

DESIGN

The study entailed cross-sectional analyses of data from 2 joint observational studies, the CoDAM Study and the Hoorn Study.

RESULTS

In total, 974 subjects aged 42-87 y were included in the study. The mean (+/-SD) GI was 57 +/- 4 and the mean GL was 130 +/- 39. Dairy products, potatoes and other tubers, cereal products, and fruit were the main predictive food groups for GI. GL was closely correlated with intake of total carbohydrates (r(s) = 0.97), which explained >95% of the variation in GL. After adjustment for potential confounders, GI was significantly inversely associated with HDL cholesterol and positively associated with fasting insulin, the homeostasis model assessment index of insulin resistance, the ratio of total to HDL cholesterol, and CRP. No association was observed between GL and any of the metabolic risk factors, except for a borderline significant positive association with CRP.

CONCLUSIONS

In this population, a low-GI diet, which is high in dairy and fruit but low in potatoes and cereals, is associated with improved insulin sensitivity and lipid metabolism and reduced chronic inflammation. GL is highly correlated with carbohydrate intake and is not clearly associated with the investigated metabolic risk factors.

Dietary glycemic index, dietary glycemic load, blood lipids, and C-reactive protein

Carbohydrate quantity and quality may influence the risk of cardiovascular disease through blood lipid concentrations and inflammation. We measured dietary glycemic index (GI) and dietary glycemic load (GL) among 18137 healthy women > or = 45 years old without diagnosed diabetes using a food-frequency questionnaire. We assayed fasting total, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) cholesterol; LDL/HDL cholesterol ratio; triacylglycerols (TG); and C-reactive protein (CRP). We evaluated associations with dietary GI and GL using a cross-sectional design, adjusting for age, body mass index, lifestyle factors, and other dietary factors. Dietary GI was significantly associated with HDL and LDL cholesterol, LDL/HDL cholesterol ratio, TG, and CRP (comparing top to bottom quintile difference in HDL cholesterol = -2.6 mg/dL, LDL cholesterol = 2.2 mg/dL, LDL/HDL cholesterol ratio = 0.16, TG = 12 mg/dL, and CRP = 0.21 mg/L). Dietary GL was associated with HDL cholesterol, LDL/HDL cholesterol ratio, and TG (comparing top to bottom quintile HDL cholesterol = -4.9 mg/dL, LDL/HDL cholesterol ratio = 0.24, and TG = 13 mg/dL). Differences in blood lipids and CRP between extreme quintiles of dietary GI and GL were small, but may translate into a clinically meaningful difference in cardiovascular risk.

Convergence of obesity and high glycemic diet on compounding diabetes and cardiovascular risks in modernizing China: an emerging public health dilemma

As China is undergoing dramatic development, it is also experiencing major societal changes, including an emerging obesity epidemic, with the prevalence of overweight and obesity doubling in the past decade. However, the implications of a high glycemic index (GI) and glycemic load (GL) traditional Chinese diet are adversely changing in modern times, as a high-glycemic diet is becoming a greater contributor to diabetes and cardiovascular risks in a population with rising obesity and decreasing physical activity. Specifically, a high GI diet adversely impacts metabolism and appetite control regulation, and notably confers substantially greater risk of weight gain, type 2 diabetes, cardiovascular disease, and certain cancers among overweight and obese individuals (P<0.05 for all); leading to an emerging vicious cycle of compounding adverse health risks. Notably, while no elevated risk of cardiovascular disease and type 2 diabetes were observed with higher GL intake among normal weight individuals, among overweight individuals, higher GL was strongly associated with higher risk of coronary heart disease (RR=2.00, 95%CI: 1.31-2.96), stroke (RR=2.13, 1.28-3.53), and type 2 diabetes (RR=1.52, 1.22-1.89 among Chinese). Additionally, the influx of Western-diets rich in saturated fats and high-glycemic sugar-sweetened beverages also threaten the health of the population. This review highlights the emerging adverse convergence of a high-glycemic Asian diet with a Chinese society experiencing an emerging obesity epidemic, and the important implications of these combined factors on compounding cardiometabolic risks. Potential policy directions in China are also discussed.

Dietary glycemic index, dietary glycemic load and mortality among men with established cardiovascular disease

BACKGROUND/OBJECTIVES

In men with established cardiovascular disease, the effect of diets with high glycemic index (GI) and glycemic load (GL) is unknown. We tested the hypothesis that diets with higher GI and GL are associated with increased mortality in men with established cardiovascular disease.

SUBJECTS/METHODS

We measured dietary GI and GL using food-frequency questionnaires in 4617 men, 45-79 years old, with a history of cardiovascular disease. The men were followed for cardiovascular mortality (6-year follow-up, 608 cases) and all-cause mortality (8-year follow-up, 1303 cases) using the Swedish cause-of-death and death registers. We used Cox models with age as the timescale and adjusted for body mass index, physical activity, history of hypertension and diabetes, family history of myocardial infarction, aspirin use, cigarette smoking and dietary factors to estimate incidence rate ratios (RRs).

RESULTS

Comparing top to bottom quartiles of dietary GI, the RR for cardiovascular mortality was 0.86 (95% confidence interval (CI) 0.67-1.10, P for linear trend=0.21), and the RR for all-cause mortality was 1.00 (95% CI 0.85-1.19, P for linear trend=0.87). Compared to quartile 1, the RR for men with dietary GL in quartile 4 was 1.02 (95% CI 0.70-1.49, P for linear trend=0.81) for cardiovascular and 1.15 (95% CI 0.89-1.49, P for linear trend=0.20) for all-cause mortality.

CONCLUSIONS

In this population of men with prior cardiovascular disease, dietary GI and GL were not associated with cardiovascular or all-cause mortality.