Glycemic index in the diet of European outpatients with type 1 diabetes: relations to glycated hemoglobin and serum lipids

BACKGROUND: Little is known about the variation of the glycemic index (GI) in the diet of European outpatients with type 1 diabetes and how the GI of a commonly consumed diet is associated with metabolic control. OBJECTIVE: The present study examined the calculated dietary GI of European outpatients with type 1 diabetes for possible relations to glycated hemoglobin (Hb A(1c)) and serum lipid concentrations. DESIGN: The relation of the GI (calculated from a 3-d dietary record) to Hb A(1c), serum cholesterol (total, LDL, and HDL), and fasting triacylglycerol was analyzed in 2810 people with type 1 diabetes from the EURODIAB Complications Study. RESULTS: The GI was independently related to Hb A(1c) (P = 0.0001). Compared with the highest GI quartile (median GI: 89), adjusted Hb A(1c) in the lowest GI quartile (median GI: 75) was 11% lower in patients from southern European centers and 6% lower in patients from northern, western, and eastern European centers. Of the serum lipids, only the HDL cholesterol in patients from these European centers was independently related to the GI (P = 0.002). In southern European centers, the consumption of pasta, temperate-climate fruit, white bread, and potatoes largely determined the patients' dietary GI, whereas in the northern, western, and eastern European centers, consumption of bread, potatoes, and temperate-climate fruit was most relevant. CONCLUSIONS: This study in European patients with type 1 diabetes showed that a lower dietary GI is related to lower Hb A(1c) concentrations, independently of fiber intake. The consumption of bread and pasta had the biggest effect on the overall dietary GI of European outpatients.     

Glycemic load, glycemic index, and pancreatic cancer risk in the Netherlands Cohort Study

BACKGROUND: Recent studies of pancreatic cancer suggest a role for hyperinsulinemia in carcinogenesis. Because insulin is secreted in response to elevated blood glucose concentrations, dietary factors that increase these concentrations may be important in pancreatic carcinogenesis. OBJECTIVE: The objective was to examine prospectively the relation between pancreatic cancer risk and dietary glycemic load (GL), overall glycemic index (GI), and intake of total carbohydrates and mono- and disaccharides. DESIGN: The Netherlands Cohort Study consisted of 120,852 men and women who completed a baseline questionnaire in 1986. After 13.3 y of follow-up, 408 pancreatic cancer cases were detected, 66% of which were microscopically confirmed. A validated 150-item food-frequency questionnaire, completed at baseline, was used to calculate carbohydrate and mono- and disaccharide intakes and the GL and GI of the diet. RESULTS: Dietary GL, GI, or intake of carbohydrates and mono- and disaccharides were not associated with pancreatic cancer risk in this cohort. Also, the associations were not modified by sex. Our results did not change after the analysis was restricted to microscopically confirmed pancreatic cancer cases or after individuals who reported a history of diabetes at baseline were excluded from the analyses. CONCLUSIONS: Overall, our findings do not support the hypothesis that GL, GI, or intake of carbohydrates and mono- and disaccharides are positively associated with pancreatic cancer risk. This is in agreement with previous prospective studies that investigated the relation between GL and GI and pancreatic cancer risk.     

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.     

Dietary glycemic index and load in relation to metabolic risk factors in Japanese female farmers with traditional dietary habits

BACKGROUND: Little is known about the relation of dietary glycemic index (GI) and glycemic load (GL) to metabolic risk factors, particularly in non-Western populations. OBJECTIVE: We examined the cross-sectional associations between dietary GI and GL and several metabolic risk factors in healthy Japanese women with traditional dietary habits. DESIGN: The subjects were 1354 Japanese female farmers aged 20-78 y from 5 regions of Japan. Dietary GI and GL were assessed with a self-administered diet-history questionnaire. Body mass index (BMI) was calculated as weight (kg) divided by the square of height (m). Fasting blood samples were collected for biochemical measurements. RESULTS: The mean dietary GI was 67, and the mean dietary GL (/1000 kcal) was 88 (GI for glucose = 100). White rice (GI = 77) was the major contributor to dietary GI and GL (58.5%). After adjustment for potential dietary and nondietary confounding factors, dietary GI was positively correlated with BMI (n = 1354; P for trend = 0.017), fasting triacylglycerol (n = 1349; P for trend = 0.001), fasting glucose (n = 764; P for trend = 0.022), and glycated hemoglobin (n = 845; P for trend = 0.038). Dietary GL was independently negatively correlated with HDL cholesterol (n = 1354; P for trend = 0.004) and positively correlated with fasting triacylglycerol (P for trend = 0.047) and fasting glucose (P for trend = 0.012). CONCLUSIONS: Both dietary GI and GL are independently correlated with several metabolic risk factors in subjects whose dietary GI and GL were primarily determined on the basis of the GI of white rice.     

Dietary glycemic index and glycemic load and the risk of type 2 diabetes in older adults

BACKGROUND: It is unclear whether immediate dietary effects on blood glucose influence the risk of developing type 2 diabetes. OBJECTIVE: The objective of this study was to examine whether the dietary glycemic index (GI) and glycemic load (GL) were associated with the risk of type 2 diabetes in older adults. DESIGN: The Health, Aging, and Body Composition Study is a prospective cohort study of 3075 adults who were 70-79 y old at baseline (n=1898 for this analysis). The intakes of specific nutrients and food groups and the risk of type 2 diabetes over a 4-y period were examined according to dietary GI and GL. RESULTS: Dietary GI was positively associated with dietary carbohydrate and negatively associated with the intakes of protein, total fat, saturated fat, alcohol, vegetables, and fruit. Dietary GL was positively associated with dietary carbohydrate, fruit, and fiber and negatively associated with the intakes of protein, total fat, saturated fat, and alcohol. Persons in the higher quintiles of dietary GI or GL did not have a significantly greater incidence of type 2 diabetes. CONCLUSIONS: These findings do not support a relation between dietary GI or GL and the risk of type 2 diabetes in older adults. Because dietary GI and GL show strong nutritional correlates, the overall dietary pattern should be considered.     

Association between carbohydrate intake and serum lipids

BACKGROUND: The effect of dietary carbohydrate on blood lipids has received considerable attention in light of the current trend in lowering carbohydrate intake for weight loss. OBJECTIVES: To evaluate the association between carbohydrate intake and serum lipids. METHODS: Blood samples and 24-hour dietary and physical activity recall interviews were obtained from each subject at quarterly intervals for five consecutive quarters between 1994 and 1998 from 574 healthy adults in Central Massachusetts. Relationships between serum lipids and dietary carbohydrate factors were assessed using linear mixed models and adjusting for other risk factors known to be related to blood lipids. Both cross-sectional and longitudinal results were reported. RESULTS: Cross-sectional analysis results from this study suggest that higher total carbohydrate intake, percentage of calories from carbohydrate, glycemic index (GI) and/or glycemic load (GL) are related to lower high-density lipoprotein cholesterol (HDL-C) and higher serum triacylglycerol levels, while higher total carbohydrate intake and/or GL are related to lower total and low-density lipoprotein cholesterol (LDL-C) levels. In a one-year longitudinal analysis, GL was positively associated with total and LDL-C levels, and there was an inverse association between percentage of calories from carbohydrate and HDL-C levels. CONCLUSIONS: Results suggest that there is a complex and predominantly unfavorable effect of increased intake of highly processed carbohydrate on lipid profile, which may have implications for metabolic syndrome, diabetes, and coronary heart disease. Further studies in the form of randomized controlled trials are required to investigate these associations and determine the implications for lipid management.     

Dietary glycemic index and glycemic load are associated with high-density-lipoprotein cholesterol at baseline but not with increased risk of diabetes in the Whitehall II study

BACKGROUND: Findings of the effect of dietary glycemic index (GI) and glycemic load (GL) on the risk of incident diabetes are inconsistent. OBJECTIVE: We examined the associations of dietary GI and GL with clinical variables at baseline and the incidence of diabetes. DESIGN: The 7321 white Whitehall II participants (71% men) attending screening in 1991-1993, free of diabetes at baseline, and with food-frequency questionnaire data were followed for 13 y. RESULTS: At baseline, dietary GI and GL were associated inversely with HDL cholesterol, and GI was associated directly with triacylglycerols. Dietary GI and GL were related inversely to fasting glucose and directly to 2-h postload glucose, but only the association between GI and 2-h postload glucose was robust to statistical adjustments for employment grade, physical activity, smoking status, and intakes of alcohol, fiber, and carbohydrates. High-dietary GI was not associated with increased risk of incident diabetes. Hazard ratios (HRs) across sex-specific tertiles of dietary GI were 1.00, 0.95 (95% CI: 0.73, 1.24), and 0.94 (95% CI: 0.72, 1.22) (adjusted for sex, age, and energy misreporting; P for trend = 0.64). Corresponding HRs across tertiles of dietary GL were 1.00, 0.92 (95% CI: 0.71, 1.19), and 0.70 (95% CI: 0.54, 0.92) (P for trend = 0.01). The protective effect on diabetes risk remained significant after adjustment for employment grade, smoking, and alcohol intake but not after further adjustment for carbohydrate and fiber intakes. CONCLUSION: The proposed protective effect of low-dietary GI and GL diets on diabetes risk could not be confirmed in this study.     

Dietary glycemic index and glycemic load in relation to HbA1c in Japanese obese adults: a cross-sectional analysis of the Saku Control Obesity Program

ABSTRACT: BACKGROUND: Dietary glycemic index or load is thought to play an important role in glucose metabolism. However, few studies have investigated the relation between glycemic index (GI) or load (GL) and glycemia in Asian populations. In this cross-sectional analysis of a randomized controlled trial, the Saku Control Obesity Program, we examined the relation between the baseline GI or GL and glycemia (HbA1c and fasting plasma glucose [FPG] levels), insulin resistance (HOMA-IR), beta-cell function (HOMA-beta), and other metabolic risk factors (lipid levels, diastolic and systolic blood pressure, and adiposity measures). METHODS: The participants were 227 obese Japanese women and men. We used multiple linear regression models and logistic regression models to adjust for potential confounding factors such as age, sex, visceral fat area, total energy intake, and physical activity levels. RESULTS: After adjustments for potential confounding factors, GI was not associated with HbA1c, but GL was positively associated with HbA1c. For increasing quartiles of GI, the adjusted mean HbA1c were 6.3%, 6.7%, 6.4%, and 6.4% (P for trend = 0.991). For increasing quartiles of GL, the adjusted mean HbA1c were 6.2%, 6.2%, 6.6%, and 6.5% (P for trend = 0.044). In addition, among participants with HbA1c >= 7.0%, 20 out of 28 (71%) had a high GL (>= median); the adjusted odds ratio for HbA1c >= 7.0% among participants with higher GL was 3.1 (95% confidence interval [CI] = 1.2 to 8.1) compared to the participants with a lower GL (= 150 mg/dL, 13 participants (81.3%) had a higher GL; the adjusted odds ratio for FPG >= 150 mg/dL among participants with a higher GL was 8.5 (95% confidence interval = 1.7 to 43.4) compared to those with a lower GL. In contrast, GI and GL were not associated with metabolic risk factors other than glycemia. CONCLUSIONS: Our findings suggest that participants with poor glycemic control tend to have a higher GL in an obese Japanese population.     

Dietary glycemic load and macronutrient intake in healthy Italian children

The objective is of this study is to examine the relationship of dietary glycemic load (GL) and overall glycemic index (OGI) with macronutrients intake, body mass index (BMI) and insulin sensitivity in healthy children. The subjects comprised of 105 healthy non-obese eight-years old children, 60 boys and 45 girls. A Food Frequency Questionnaire (FFQ) evaluating dietary habits, GL and OGI. Insulin sensitivity was evaluated by the homeostatic model assessment (HOMA). GL was positively associated with dietary total (correlation coefficient, r=0.57) and starch (r=0.67) carbohydrates, daily consumption of pasta and white bread, cooked potatoes, bakery products and cookies, and negatively with dietary fats (r=-0.52). OGI was positively associated with daily consumption of white bread and cookies, and negatively associated with soluble carbohydrates (r=-0.35), and consumption of fibres, proteins, fruit, legumes and carrots. No significant association was found of GL or OGI with BMI or insulin sensitivity. In healthy children, GL and OGI may represent a useful indicator of quality of diet.     

Association between dietary glycemic index, glycemic load, and body mass index in the Inter99 study: is underreporting a problem?

BACKGROUND: The few studies examining the potential associations between glycemic index (GI), glycemic load (GL), and body mass index (BMI) have provided no clear pictures. Underreporting of energy intake may be one explanation for this. OBJECTIVE: We examined the associations between GI, GL, and BMI by focusing on the confounding factor of total energy intake and the effect of exclusion of low energy reporters (LERs). DESIGN: This was a cross-sectional study of 6334 subjects aged 30-60 y. Dietary intake was estimated from a food-frequency questionnaire. GI and GL were estimated by using white bread as the reference food. Underreporting of energy intake was assessed as reported energy intake divided by basal metabolic rate (EI/BMR); LERs were defined as those having an EI/BMR < 1.14. Univariate and multiple linear regression models were used to test for associations between GI, GL, and BMI. The confounders were sex, age, smoking, physical activity, alcohol intake, and energy intake. All analyses were conducted on 1) the entire population and 2) a subsample excluding LERs. RESULTS: In the univariate analyses of the entire population, GL was inversely associated with BMI. No association was observed for GI. After full adjustment (including energy intake), both GI and GL were positively associated with BMI. When LERs were excluded, GL was positively associated with BMI in all analyses, and GI was positively associated with BMI in the multiple analyses. CONCLUSIONS: We showed a positive association between GI, GL, and BMI. Energy adjustment and the exclusion of LERs significantly affected the results of the analysis; thus, we stress the importance of energy adjustment.     

Higher glycemic index and glycemic load diet is associated with increased risk of esophageal squamous cell carcinoma: a case-control study

Several studies have indicated the association between intake of foods high in dietary glycemic index (GI) and glycemic load (GL) with an increased risk of digestive tract cancers. We hypothesized that GI and GL may be associated with risk of esophageal squamous cell carcinoma (ESCC) in a high-risk population in Iran. In total, we interviewed 47 cases with incident of ESCC and 96 frequency-matched hospital controls, then calculated the average dietary GI and GL via a validated food frequency questionnaire. Dietary GL was calculated as a function of GI, carbohydrate content, and frequency of intake of certain foods. Dietary GI and GL levels were significantly higher among the ESCC cases compared with the controls (P < .05). After adjustment for potential confounders, those in the highest tertile of dietary GI had 2.95 times higher risk of ESCC compared with those in the lowest (95% confidence interval, 1.68-3.35; P for trend = .002). In addition, being in the highest tertile of dietary GL was positively associated with an ESCC risk (odds ratio, 3.49; 95% confidence interval, 2.98-4.41; P for trend = .001). Findings of the present study indicate that diets with high GI and GL might have potentially unfavorable effects on ESCC risk and suggest a possible role for excess circulating insulin and related insulin-like growth factor 1 in esophageal cancer development.     

Dietary glycemic load assessed by food-frequency questionnaire in relation to plasma high-density-lipoprotein cholesterol and fasting plasma triacylglycerols in postmenopausal women

BACKGROUND: In metabolic studies, both greater carbohydrate intakes and higher glycemic indexes (GIs) raise fasting triacylglycerol concentrations. In epidemiologic studies, dietary glycemic load (GL) is positively associated with risk of coronary artery disease and type 2 diabetes. OBJECTIVE: We examined both the physiologic relevance of GI and GL and the ability of dietary questionnaires to measure these variables. DESIGN: In the Nurses' Health Study, we measured plasma triacylglycerol concentrations in fasting blood samples from 185 healthy postmenopausal women and HDL-cholesterol concentrations in an additional 95 nonfasting samples. Dietary carbohydrate, GI, and GL were assessed by use of semiquantitative food-frequency questionnaires. The cross-sectional associations between these 3 variables and plasma triacylglycerol and HDL were assessed, with adjustment for potential confounding factors. RESULTS: For the lowest and highest quintiles of GL, the multivariate-adjusted geometric mean triacylglycerol concentrations were 0.98 and 1.75 mmol/L (87 and 155 mg/dL; P for trend < 0.001). Both overall GI (P for trend = 0.03) and carbohydrate (P for trend < 0.01) contributed independently to the strong positive association between GL and fasting triacylglycerol concentrations. GL was also inversely associated with HDL-cholesterol concentrations. For the lowest and highest quintiles of GL, the mean HDL-cholesterol concentrations were 1.50 and 1.34 micromol/L (58 and 52 mg/dL; P for trend = 0.03). The relation between GL and fasting triacylglycerol concentrations differed significantly by body mass index (BMI; in kg/m(2)) categories (P < 0.001 for interaction). For the lowest to the highest quintiles of GL, the mean triacylglycerol concentrations were 0.92 and 2.24 mmol/L (81 and 198 mg/dL) in women with BMIs > 25 (P for trend < 0.001) and 1.02 and 1.42 mmol/L (90 and 126 mg/dL) in women with BMIs < or = 25 (P for trend < 0.001). CONCLUSION: These data support the physiologic relevance of the GL as a potential risk factor for coronary artery disease in free-living women, particularly those prone to insulin resistance. These findings also document the ability of a semiquantitative food-frequency questionnaire to assess dietary GIs and GLs.     

Whole grains, bran, and germ in relation to homocysteine and markers of glycemic control, lipids, and inflammation 1

BACKGROUND: Intake of whole grains is inversely associated with risk of diabetes and ischemic heart disease in observational studies. The lower risk associated with high whole-grain intakes may be mediated through improvements in glycemic control, lipid profiles, or reduced inflammation. OBJECTIVE: The aim was to examine whether the intake of whole grains, bran, and germ is related to homocysteine, plasma markers of glycemic control (fasting insulin, hemoglobin A1c, C-peptide, and leptin), lipids (total cholesterol, triacylglycerol, HDL cholesterol, and LDL cholesterol), and inflammation (C-reactive protein, fibrinogen, and interleukin 6). DESIGN: This was a cross-sectional study of the relations of whole grains, bran, and germ intakes with homocysteine and markers of glycemic control, lipids, and inflammation in 938 healthy men and women. RESULTS: Whole-grain intake was inversely associated with homocysteine and markers of glycemic control. Compared with participants in the bottom quintile of whole-grain intake, participants in the highest quintile had 17%, 14%, 14%, and 11% lower concentrations of homocysteine (P < 0.01), insulin (P = 0.12), C-peptide (P = 0.03), and leptin (P = 0.03), respectively. Inverse associations were also observed with total cholesterol (P = 0.02), HDL cholesterol (P = 0.05), and LDL cholesterol (P = 0.10). Whole-grain intake was not associated with the markers of inflammation. Whole-grain intake was most strongly inversely associated with markers of glycemic control in this population. CONCLUSION: The results suggest a lower risk of diabetes and heart disease in persons who consume diets high in whole grains.     

Dietary patterns related to glycemic index and load and risk of premenopausal and postmenopausal breast cancer in the Western New York Exposure and Breast Cancer Study

BACKGROUND: Reduced rank regression (RRR) has been used to identify dietary patterns that predict variation in a selected risk factor and may be useful in describing dietary exposures associated with glycemic index (GI) and glycemic load (GL). OBJECTIVE: To estimate breast cancer risk, we compared the relative utility of RRR-derived dietary patterns predictive of GI and GL with those of simple GI and GL. DESIGN: RRR was used to identify dietary patterns predicting GI and GL from food-frequency data obtained in the Western New York Exposure and Breast Cancer Study (1166 cases, 2105 controls). Odds ratios (ORs) and 95% CIs were estimated with unconditional logistic regression, adjusted for energy and nondietary breast cancer risk factors. RESULTS: Sweets, refined grains, and salty snacks explained 34% of the variance in GI and 68% of the variance in GL. In general, breast cancer risks were not associated with GI, GL, or dietary pattern score. However, we observed a significant reduction in postmenopausal breast cancer risk with GI and GL pattern scores combined (OR: 0.68; 95% CI: 0.50, 0.93), especially in women with a body mass index (in kg/m(2)) >or=25 (OR: 0.64; 95% CI: 0.44, 0.93). Conversely, in premenopausal women, increased risks were associated with high GL pattern scores only for women with a body mass index >or=25 (OR: 2.21; 95% CI: 1.04, 4.69). CONCLUSIONS: Although RRR may be useful in studies of diet and disease, our results suggest that RRR dietary patterns based on GI and GL provide similar information regarding the association between breast cancer, GI, and GL.     

Dietary glycemic load, glycemic index, and carbohydrate and risk of breast cancer in the Women's Health Initiative

Dietary glycemic load (GL), glycemic index (GI), and carbohydrate could be associated with breast cancer risk by influencing long-term blood glucose and insulin concentrations. We examined associations between GL, GI, and carbohydrate and incident breast cancer in 148,767 Women's Heath Initiative (WHI) participants. Dietary variables were estimated from food frequency questionnaires administered at baseline. Self-reported breast cancers during follow-up were confirmed by medical records review. Cox proportional hazards regression modeled time to breast cancer within quintiles of GL, GI, and carbohydrate. There were 6,115 total breast cancers after a median follow-up of 8.0 yr. We observed no associations between GL, GI, or carbohydrate and total incident breast cancer, with hazard ratios and 95% confidence intervals for the highest vs. lowest quintiles of 1.08, 0.92-1.29 (P for trend = 0.27); 1.01, 0.91-1.12 (P = 0.74); and 0.95, 0.80-1.14 (P = 0.98), respectively. There was a trend toward significance for the positive association between GL and in situ cancers (1.40, 0.94-2.13; P = 0.07). Although there was no evidence of associations between GL, GI, or carbohydrate and total breast cancer risk in WHI participants, the suggestion of an association between GL and risk of in situ cancers requires further investigation.     

Carbohydrate intake, glycemic index, glycemic load, and risk of postmenopausal breast cancer in a prospective study of French women

BACKGROUND: Diets high in carbohydrates may result in chronically elevated insulin concentrations and may affect breast cancer risk by stimulation of insulin receptors or through insulin-like growth factor I (IGF-I)-mediated mitogenesis. Insulin response to carbohydrate intake is increased in insulin-resistant states such as obesity. OBJECTIVE: We sought to evaluate carbohydrate intake, glycemic index (GI), and glycemic load (GL) and subsequent overall and hormone-receptor-defined breast cancer risk among postmenopausal women. DESIGN: A prospective cohort analysis of dietary carbohydrate and fiber intakes was conducted among 62 739 postmenopausal women from the E3N French study who had completed a validated dietary history questionnaire in 1993. During a 9-y period, 1812 cases of pathology-confirmed breast cancer were documented through follow-up questionnaires. Nutrients were categorized into quartiles and energy-adjusted with the regression-residual method. Cox model-derived relative risks (RRs) were adjusted for known determinants in breast cancer. RESULTS: Dietary carbohydrate and fiber intakes were not associated with overall breast cancer risk. Among overweight women, we observed an association between GI and breast cancer (RR(Q1-Q4): 1.35; 95% CI: 1.00, 1.82; P for trend = 0.04). For women in the highest category of waist circumference, the RR(Q1-Q4) was 1.28 (95% CI: 0.98, 1.67; P for trend = 0.10) for carbohydrates, 1.35 (95% CI: 1.04, 1.75; P for trend = 0.01) for GI, and 1.37 (95% CI: 1.05, 1.77; P for trend = 0.003) for GL. We also observed a direct association between carbohydrate intake, GL, and estrogen receptor-negative breast cancer risk. CONCLUSIONS: Rapidly absorbed carbohydrates are associated with postmenopausal breast cancer risk among overweight women and women with large waist circumference. Carbohydrate intake may also be associated with estrogen receptor-negative breast cancer.     

The Effect of a Low Fructose and Low Glycemic Index/Load (FRAGILE) Dietary Intervention on Indices of Liver Function,Cardiometabolic Risk Factors,and Body Composition in Children and Adolescents With Nonalcoholic Fatty Liver Disease (NAFLD)

Background: Nonalcoholic fatty liver disease (NAFLD) is a common liver disease in obese children. Diets high in added fructose (high fructose corn syrup; HFCS) and glycemic index (GI)/glycemic load (GL) are associated with increased risk of NAFLD. Lifestyle modification is the main treatment, but no guidelines regarding specific dietary interventions for childhood NAFLD exist. We hypothesized that reductions in dietary fructose (total, free, and HFCS)/GI/GL over 6 months would result in improvements in body composition and markers of liver dysfunction and cardiometabolic risk in childhood NAFLD. Methods: Children and adolescents with NAFLD (n = 12) and healthy controls (n = 14) 7–18 years were studied at baseline and 3 and 6 months post–dietary intervention. Plasma markers of liver dysfunction (ALT, AST, γGT), cardiometabolic risk (TG, total cholesterol, LDL‐HDL cholesterol, Apo‐B100, Apo‐B48, Apo‐CIII, insulin, homeostasis model of assessment of insulin resistance [HOMA‐IR]), inflammation (TNF‐α, IL‐6, IL‐10), anthropometric, and blood pressure (BP) were studied using validated methodologies. Results: Significant reductions in systolic BP (SBP), percentage body fat (BF), and plasma concentrations of ALT (P = .04), Apo‐B100 (P < .001), and HOMA‐IR were observed in children with NAFLD at 3 and 6 months (P < .05). Dietary reductions in total/free fructose/HFCS and GL were related to reductions in SBP (P = .01), ALT (P = .004), HOMA‐IR (P = .03), and percentage BF in children with NAFLD. Reductions in dietary GI were associated with reduced plasma Apo‐B100 (P = .02) in both groups. With the exception of Apo‐B100, no changes in laboratory variables were observed in the control group. Conclusion: Modest reductions in fructose (total/free, HFCS) and GI/GL intake result in improvements of plasma markers of liver dysfunction and cardiometabolic risk in childhood NAFLD.     

Whole-grain intake is favorably associated with metabolic risk factors for type 2 diabetes and cardiovascular disease in the Framingham Offspring Study

BACKGROUND: The influence of whole grains on cardiovascular disease risk may be mediated through multiple pathways, eg, a reduction in blood lipids and blood pressure, an enhancement of insulin sensitivity, and an improvement in blood glucose control. OBJECTIVE: The objective was to examine the association between diets rich in whole- or refined-grain foods and several metabolic markers of disease risk in the Framingham Offspring Study cohort. DESIGN: Whole-grain intake and metabolic risk markers were assessed in a cross-sectional study of 2941 subjects. RESULTS: After adjustment for potential confounding factors, whole-grain intake was inversely associated with body mass index (: 26.9 in the lowest and 26.4 in the highest quintile of intake; P for trend = 0.06), waist-to-hip ratio (0.92 and 0.91, respectively; P for trend = 0.005), total cholesterol (5.20 and 5.09 mmol/L, respectively; P for trend = 0.06), LDL cholesterol (3.16 and 3.04 mmol/L, respectively; P for trend = 0.02), and fasting insulin (205 and 199 pmol/L, respectively; P for trend = 0.03). There were no significant trends in metabolic risk factor concentrations across quintile categories of refined-grain intake. The inverse association between whole-grain intake and fasting insulin was most striking among overweight participants. The association between whole-grain intake and fasting insulin was attenuated after adjustment for dietary fiber and magnesium. CONCLUSION: Increased intakes of whole grains may reduce disease risk by means of favorable effects on metabolic risk factors.     

Dietary Glycemic Load,Glycemic Index,and Carbohydrate and Risk of Breast Cancer in the Women's Health Initiative

Dietary glycemic load (GL), glycemic index (GI), and carbohydrate could be associated with breast cancer risk by influencing long-term blood glucose and insulin concentrations. We examined associations between GL, GI, and carbohydrate and incident breast cancer in 148,767 Women's Heath Initiative (WHI) participants. Dietary variables were estimated from food frequency questionnaires administered at baseline. Self-reported breast cancers during follow-up were confirmed by medical records review. Cox proportional hazards regression modeled time to breast cancer within quintiles of GL, GI, and carbohydrate. There were 6,115 total breast cancers after a median follow-up of 8.0 yr. We observed no associations between GL, GI, or carbohydrate and total incident breast cancer, with hazard ratios and 95% confidence intervals for the highest vs. lowest quintiles of 1.08, 0.92–1.29 (P for trend = 0.27); 1.01, 0.91–1.12 (P = 0.74); and 0.95, 0.80–1.14 (P = 0.98), respectively. There was a trend toward significance for the positive association between GL and in situ cancers (1.40, 0.94–2.13; P = 0.07). Although there was no evidence of associations between GL, GI, or carbohydrate and total breast cancer risk in WHI participants, the suggestion of an association between GL and risk of in situ cancers requires further investigation.     

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

OBJECTIVE: To examine the correlation between dietary glycemic index (GI) and cardiovascular disease (CVD) risk factors among subjects who consume white rice as a staple food. DESIGN: A cross-sectional study was conducted to explore the associations between dietary GI, dietary glycemic load (GL) and dietary intakes, and CVD risk factors. Dietary GI and GL were calculated from a 3-day (including two consecutive weekdays and one holiday) dietary records. SETTING: A weight-reduction program at a municipal health center in Tokyo, Japan. SUBJECTS: A total of 32 women aged 52.5+/-7.2 y participated in the weight-reduction program. RESULT: The GI food list made for the current study calculated for 91% of carbohydrate intakes measured. The mean dietary GI was 64+/-6, and the mean dietary GL was 150+/-37. Individuals in the highest tertile of GI consumed more carbohydrate, mostly from white rice (P<0.001), and less fat (P<0.01). Individuals in all three groups by tertile of GL showed similar tendencies. In the lowest GI tertile, the highest concentration of HDL-cholesterol and lowest concentration of triacylglycerol and immunoreactive insulin were observed (P<0.01). In the lowest GL tertile, the highest concentration of HDL-cholesterol and the lowest concentration of triacylglycerol were observed (P<0.05). CONCLUSION: Calculated dietary GI and GL were positively associated with CVD risk factors among the Japanese women who consumed white rice as a staple food.