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Objective: Diets high in total and saturated fat are associated with insulin resistance. This study examined the effects of feeding monounsaturated, saturated, and trans fatty acids on insulin action in healthy adults., Research Design and Methods: A randomized, double-blind, crossover study was conducted comparing three controlled 4-week diets (57% carbohydrate, 28% fat, and 15% protein) enriched with different fatty acids in 25 healthy men and women. The monounsaturated fat diet (M) had 9% of energy as C18:1cis (oleic acid). The saturated fat diet (S) had 9% of energy as palmitic acid, and the trans fatty acid diet (T) had 9% as C18:1trans. Body weight was kept constant throughout the study. After each diet period, insulin pulsatile secretion, insulin sensitivity index (S(I)) by the minimal model method, serum lipids, and fat oxidation by indirect calorimetry were measured., Results: Mean S(I) for the M, S, and T diets was 3.44 +/- 0.26, 3.20 +/- 0.26, and 3.40 +/- 0.26 x 10(-4) min(-1). microU(-1). ml(-1), respectively (NS). S(I) decreased by 24% on the S versus M diet in overweight subjects but was unchanged in lean subjects (NS). Insulin secretion was unaffected by diet, whereas total and HDL cholesterol increased significantly on the S diet. Subjects oxidized the least fat on the M diet (26.0 +/- 1.5 g/day) and the most fat on the T diet (31.4 +/- 1.5 g/day) (P = 0.02)., Conclusions: Dietary fatty acid composition significantly influenced fat oxidation but did not impact insulin sensitivity or secretion in lean individuals. Overweight individuals were more susceptible to developing insulin resistance on high-saturated fat diets.

Objective: Dietary interventions in patients with type 2 diabetes (T2D) are important for preventing long-term complications. Although a healthy diet is crucial, there is still uncertainty about the optimal macronutrient composition. We performed a meta-analysis comparing diets high in cis-monounsaturated fatty acids (MUFA) to diets high in carbohydrates (CHO) or in polyunsaturated fatty acids (PUFA) on metabolic risk factors in patients with T2D.Research Design and Methods: We systematically reviewed PubMed, MEDLINE, and Cochrane databases and prior systematic reviews and meta-analyses to identify interventions assessing HbA1c, fasting plasma glucose and insulin, LDL and HDL cholesterol, triglycerides, body weight, or systolic/diastolic blood pressure. Meta-analyses were conducted using both fixed- and random-effects models to calculate the weighted mean difference (WMD) and 95% CI.Results: We identified 24 studies totaling 1,460 participants comparing high-MUFA to high-CHO diets and 4 studies totaling 44 participants comparing high-MUFA to high-PUFA diets. When comparing high-MUFA to high-CHO diets, there were significant reductions in fasting plasma glucose (WMD -0.57 mmol/L [95% CI -0.76, -0.39]), triglycerides (-0.31 mmol/L [-0.44, -0.18]), body weight (-1.56 kg [-2.89, -0.23]), and systolic blood pressure (-2.31 mmHg [-4.13, -0.49]) along with significant increases in HDL cholesterol (0.06 mmol/L [0.02, 0.10]). When high-MUFA diets were compared with high-PUFA diets, there was a significant reduction in fasting plasma glucose (-0.87 mmol/L [-1.67, -0.07]). All of the outcomes had low to medium levels of heterogeneity, ranging from 0.0 to 69.5% for diastolic blood pressure (Phet = 0.011).Conclusions: Our meta-analysis provides evidence that consuming diets high in MUFA can improve metabolic risk factors among patients with T2D. [ABSTRACT FROM AUTHOR]

The article determines the potential role of nonnutritive sweeteners (NNS) in helping Americans to adhere to population-wide reductions in added sugars intake in the context of current usage and health perspectives. Food products such as diet soft drinks, yogurts, desserts and gum contain NNS. It discusses consumer attitudes and rationale for using or avoiding NNS. It also examines the potential effects of NNS on body weight, cardio-metabolic variables and diabetes mellitus/glycemic response.

The article discusses a systematic review of literature on the role of macronutrients, eating patterns and foods on diabetes management. Medical nutrition therapy (MNT), which is said to be an effective way to manage diabetes, maintains optimal blood glucose levels and prevent and treat the complications of the disease. The researchers searched the PubMed database using various terms that include diabetes, low-fat diet and omega-3 fatty acid.

OBJECTIVE--Fat intake, especially monounsaturated fatty acid (MUFA), has been liberalized in diabetic diets to preserve HDL cholesterol and improve glycemic control, yet the exact sources have not been clearly defined. Therefore, we assessed the effect of mixed nut consumption as a source of vegetable fat on serum lipids and HbA1c in type 2 diabetes. RESEARCH DESIGN AND METHODS--A total of 117 type 2 diabetic subjects were randomized to one of three treatments for 3 months. Supplements were provided at 475 kcal per 2,000-kcal diet as mixed nuts (75 g/day), muffins, or half portions of both. The primary outcome was change in HbA1c. RESULTS--The relative increase in MUFAs was 8.7% energy on the full-nut dose compared with muffins. Using an intention-to-treat analysis (n = 117), full-nut dose (mean intake 73 g/day) reduced HbA1C. (-0.21% absolute HbA1c units, 95% CI -0.30 to -0.11, P < 0.001) with no change after half-nut dose or muffin. Full-nut dose was significantly different from half-nut dose (P = 0.004) and muffin (P = 0001), but no difference was seen between half-nut dose and muffins. LDL cholesterol also decreased significantly after full-nut dose compared with muffin. The LDL cholesterol reduction after half-nut dose was intermediate and not significantly different from the other treatments. Apolipoprotein (apo) B and the apoB:apoA1 ratio behaved similarly. Nut intake related negatively to changes in HbA1c (r = -0.20, P = 0.033) and LDL cholesterol (r = -0.24, P = 0.011). CONCLUSIONS--Two ounces of nuts daily as a replacement for carbohydrate foods improved both glycemic control and serum lipids in type 2 diabetes. [ABSTRACT FROM AUTHOR]

The article offers clinical care guidelines for the management of cystic fibrosis-related diabetes (CFRD) from a joint effort between the Cystic Fibrosis Foundation (CFF), the American Diabetes Association (ADA), and the Pediatric Endocrine Society (PES). CFRD is considered to be the most common comorbidity in cystic fibrosis (CF) patients. The article also discusses the screening tests for CFRD and the age of screening for CFRD.

OBJECTIVE-- Consumption of sugar-sweetened beverages (SSBs), which include soft drinks, fruit drinks, iced tea, and energy and vitamin water drinks has risen across the globe. Regular consumption of SSBs has been associated with weight gain and risk of overweight and obesity, but the role of SSBs in the development of related chronic metabolic diseases, such as metabolic syndrome and type 2 diabetes, has not been quantitatively reviewed. RESEARCH DESIGN AND METHODS-- We searched the MEDLINE database up to May 2010 for prospective cohort studies of SSB intake and risk of metabolic syndrome and type 2 diabetes. We identified 11 studies (three for metabolic syndrome and eight for type 2 diabetes) for inclusion in a random-effects meta-analysis comparing SSB intake in the highest to lowest quantiles in relation to risk of metabolic syndrome and type 2 diabetes. RESULTS-- Based on data from these studies, including 310,819 participants and 15,043 cases of type 2 diabetes, individuals in the highest quantile of SSB intake (most often 1-2 servings/day) had a 26% greater risk of developing type 2 diabetes than those in the lowest quantile (none or <1 serving/month) (relative risk [RR] 1.26 [95% CI 1.12-1.41]). Among studies evaluating metabolic syndrome, including 19,431 participants and 5,803 cases, the pooled RR was 1.20 [1.02-1.42]. CONCLUSIONS-- In addition to weight gain, higher consumption of SSBs is associated with development of metabolic syndrome and type 2 diabetes. These data provide empirical evidence that intake of SSBs should be limited to reduce obesity-related risk of chronic metabolic diseases. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- Weight loss through lifestyle changes is recommended for nonalcoholic fatty liver disease (NAFLD). However, its efficacy in patients with type 2 diabetes is unproven. RESEARCH DESIGN AND METHODS -- Look AHEAD (Action for Health in Diabetes) is a 16-center clinical trial with 5,145 overweight or obese adults with type 2 diabetes, who were randomly assigned to an intensive lifestyle intervention (ILI) to induce a minimum weight loss of 7% or a control group who received diabetes support and education (DSE). In the Fatty Liver Ancillary Study, 96 participants completed proton magnetic resonance spectroscopy to quantify hepatic steatosis and tests to exclude other causes of liver disease at baseline and 12 months. We defined steatosis >5.5% as NAFLD. RESULTS -- Participants were 49% women and 68% white. The mean age was 61 years, mean BMI was 35 kg/m², mean steatosis was 8.0%, and mean aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were 20.5 and 24.2 units/l, respectively. After 12 months, participants assigned to ILI (n = 46) lost more weight (-8.5 vs. -0.05%; P < 0.01) than those assigned to DSE and had a greater decline in steatosis (-50.8 vs. - 22.8%; P = 0.04) and in A1C (-0.7 vs. -0.2%; P = 0.04). There were no significant 12-month changes in AST or ALT levels. At 12 months, 26% of DSE participants and 3% (1 of 31) of ILI participants without NAFLD at baseline developed NAFLD (P < 0.05). CONCLUSIONS -- A 12-month intensive lifestyle intervention in patients with type 2 diabetes reduces steatosis and incident NAFLD. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- To search for a better dietary approach to treat postprandial lipid abnormalities and improve glucose control in type 2 diabetic patients. RESEARCH DESIGN AND METHODS -- According to a randomized crossover design, 18 type 2 diabetic patients (aged 59 ± 5 years; BMI 27 ± 3 kg/m²) (means ± SD) in satisfactory blood glucose control on diet or diet plus metformin followed a diet relatively rich in carbohydrates (52% total energy), rich in fiber (28g/1,000 kcal), and with a low glycemic index (58%) (high-carbohydrate/high-fiber diet) or a diet relatively low in carbohydrate (45%) and rich in monounsaturated fat (23%) (low-carbohydrate/high-monounsaturated fat diet) for 4 weeks. Thereafter, they shifted to the other diet for 4 more weeks. At the end of each period, plasma glucose, insulin, lipids, and lipoprotein fractions (separated by discontinuous density gradient ultracentrifugation) were determined on blood samples taken at fasting and over 6 h after a test meal having a similar composition as the corresponding diet. RESULTS -- In addition to a significant decrease in postprandial plasma glucose, insulin responses, and glycemic variability, the high-carbohydrate/high-fiber diet also significantly improved the primary end point, since it reduced the postprandial incremental areas under the curve (IAUCs) of triglyceride-rich lipoproteins, in particular, chylomicrons (cholesterol IAUC: 0.05 ± 0.01 vs. 0.08 ± 0.02 mmol/l per 6 h; triglycerides IAUC: 0.71 ± 0.35 vs. 1.03 ± 0.58 mmol/l per 6 h, P < 0.05). CONCLUSIONS -- A diet rich in carbohydrate and fiber, essentially based on legumes, vegetables, fruits, and whole cereals, may be particularly useful for treating diabetic patients because of its multiple effects on different cardiovascular risk factors, including postprandial lipids abnormalities. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- The effects of dietary macronutrient composition on metabolic profiles in patients with type 2 diabetes have been inconsistent. This meta-analysis aimed to elucidate the effect of replacing dietary fat with carbohydrate on glucose and lipid parameters in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS-- We searched for randomized trials that investigated the effects of two kinds of prescribed diets (a low-fat, high-carbohydrate [LFHC] diet and a high-fat, low-carbohydrate [HFLC] diet); in these studies, energy and protein intake did not differ significantly between the two dietary groups. Nineteen studies that included 306 patients met our inclusion criteria. Median diet composition of carbohydrate/fat in the LFHC and HFLC diets was 58%/24% and 40%/40%, respectively. RESULTS-- Changes in values for A1C, fasting plasma glucose (FPG), and total and LDL cholesterol did not differ significantly between the LFHC and HFLC groups. However, the LFHC diet significantly increased fasting insulin and triglycerides by 8% (P = 0.02) and 13% (P < 0.001), respectively, and lowered HDL cholesterol by 6% (P < 0.001) compared with the HFLC diet. There were positive associations among the magnitude of changes in FPG, fasting insulin, and triglycerides for the diets analyzed. However, stratified analysis indicated that the increase in triglycerides was insignificant when accompanied by energy intake restriction. CONCLUSIONS-- Our findings suggested that replacing fat with carbohydrate could deteriorate insulin resistance while the adverse effect on triglycerides from the LFHC diet could be avoided by restricting energy intake to a degree sufficient for the attainment of weight reduction. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- While women with prior gestational diabetes mellitus (GDM) are more likely to display features of the metabolic syndrome, including hypertension, in the years after delivery, it is unclear whether these components are also present before pregnancy. We examined the relationship between blood pressure (BP) measured before and during early pregnancy (<20 weeks) and the risk of GDM in a nested case-control study. RESEARCH DESIGN AND METHODS -- Case (n = 381) and control (n = 942) subjects were selected from a cohort of women delivering between 1996 and 1998 and screened for GDM between 24 and 28 weeks' gestation. GDM was defined by the National Diabetes Data Group criteria. BP and covariates data were obtained by review of the medical records. Women were categorized according to BP levels recommended by the American Heart Association outside of pregnancy: < 120/80 mmHg (normal), 120-139/80-89 mmHg (prehypertension), and ≥140 and/or ≥90 mmHg or use of antihypertensive medications (hypertension). RESULTS -- During early pregnancy, women with prehypertension had a small increased risk of GDM (odds ratio [OR] 1.56 [95% CI 1.16-2.10]), and women with hypertension had a twofold increased risk of GDM (2.04 [1.14-3.65]) compared with women with normal BP after adjusting for age, race/ethnicity, gestational week of BP, BMI, and parity. Similar results were seen among the subset of women with BP levels measured before pregnancy (1.44 [0.95-2.19] for prehypertension and 2.01 [1.01-3.99] for hypertension). CONCLUSIONS -- Clinicians should be aware that women presenting with hypertension may warrant early screening or intervention to prevent GDM. [ABSTRACT FROM AUTHOR]

The article reports on a study regarding consumption of hydrogenated vegetable oils (HVOs) versus nonhydrogenated vegetable oils (non-HVOs), risk of insulin resistance and the metabolic syndrome among Iranian adult women. It found that there is a significant association between HVO consumption, risk of insulin resistance and the metabolic syndrome among the subjects. Meanwhile, higher intakes of non-HVOs are said to be linked with lower risk of insulin resistance.

OBJECTIVE -- Muscle-strengthening activities (MSAs) may increase insulin sensitivity, thereby reducing the risk of diabetes. The purpose of this study was to assess the relationship between MSAs and insulin sensitivity among American adults. RESEARCH DESIGN AND METHODS -- We analyzed data on 4,504 adults without diabetes, aged 20-79 years, who participated in the National Health and Nutrition Examination Survey 1999-2004 and had information on MSAs. Self-reported frequency (times/week) of MSAs was grouped as low (<1), moderate (1-2.9), or high (≥3). Insulin sensitivity was measured by the fasting quantitative insulin sensitivity check index x 100 (QUICKI). RESULTS -- After adjustment for age, race/ethnicity, physical activity other than MSAs, BMI, smoking, alcohol consumption, and daily total caloric intake, the mean values for QUICKI by low, moderate, and high MSA were 33.6, 33.9, and 34.2, respectively (P for linear trend = 0.008) for men and 34.2, 34.6, 34.6, respectively (P for linear trend = 0.009) for women. Mean fasting insulin (picomols per liter) concentrations were 75.0, 68.9, and 65.9, respectively (P for linear trend = 0.017) for men and 66.9, 63.3, 61.2, respectively (P for linear trend = 0.007) for women. There were no significant differences across MSA groups for fasting glucose among men or women. CONCLUSIONS -- MSA is independently associated with higher insulin sensitivity among U.S. adults. Efforts to increase MSA may be a realistic, feasible, and effective method of reducing insulin resistance among the U.S. population. [ABSTRACT FROM AUTHOR]

The article focuses on cellular mechanisms for insulin resistance in normal pregnancy and gestational diabetes mellitus (GDM). It says that the lipogenic transcription factor PPAR-γ in adipose tissue declines in obese women during pregnancy and may shift genes in metabolic pathways to favor increased lipolysis and accelerate adipose tissue insulin resistance. It states that inflammation, placental hormones, reduced adiponectin secretion and excess lipolysis conspire to cause severe insulin resistance.

OBJECTIVE -- We sought to assess the intra- and interindividual variability of glycemic index value determinations for white bread using glucose as the reference food. RESEARCH DESIGN AND METHODS -- A total of 23 healthy adults (aged 20-70 years) completed up to three sets of two visits per set. Each pair of visits assessed the glycemic response to 50 g available carbohydrates from commercial white bread and glucose, administered in random order. Glycemic index values were calculated by dividing the 2-h incremental area under the serum glucose response curve after each commercial white bread challenge by the mean area under the curve (AUC) for glucose. RESULTS -- The mean ± SE ratio of the AUC after white bread intake by the AUC after glucose intake for the first set of determinations was 78 ± 15 (n = 23; coefficient of variation [CV] 94%). When using glycemic index values calculated with the subset of participants who completed three sets of tests (n = 14), glycemic index values for each of the three sets of determinations were 78 ± 10, 60 ± 5, and 75 ± 10, respectively. CVs were 50, 28, and 50%, respectively. The mean glycemic index value of these three sets was 71 ± 6, with a CV of 30%. When an ANOVA approach was applied to these data, the interindividual CV was 17.8%, and the intra-individual variation was 42.8%. CONCLUSIONS -- These data suggest that in response to a challenge of white bread relative to glucose, within-individual variability is a greater contributor to overall variability than among individual variability. Further understanding of all the sources of variability would be helpful in better defining the utility of glycemic index values. [ABSTRACT FROM AUTHOR]

The American Heart Association (AHA) and the American Diabetes Association (ADA) have each published guidelines for cardiovascular disease prevention: the ADA has issued separate recommendations for each of the cardiovascular risk factors in patients with diabetes, and the AHA has shaped primary and secondary guidelines that extend to patients with diabetes. This statement will attempt to harmonize the recommendations of both organizations where possible but will recognize areas in which AHA and ADA recommendations differ. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of apolipoprotein (apo)E4 allele on plasma LDL cholesterol response to calorie-restricted diet therapy in type 2 diabetic patients. There were no significant differences in baseline FPG levels, HbA1c levels, BMI, and plasma levels of total cholesterol, triglyceride, and HDL cholesterol between the two apoE genotype groups, but baseline plasma levels of LDL cholesterol were significantly higher in the apoE4/3 group than in the apoE3/3 group. Body weight decreased slightly and FPG levels decreased significantly after diet therapy in both apoE genotype groups. In the apoE3/3 group, only plasma levels of triglyceride decreased significantly after diet therapy, whereas in the apoE4/3 group, plasma levels of triglyceride, total cholesterol, and LDL cholesterol decreased significantly after diet therapy. The decrease (percentage of change) in total cholesterol (-16.3 vs. -6.6%) and LDL cholesterol (-15.6 vs. -0.7%) after diet therapy was significantly greater in the apoE4/3 group than in the apoE3/3 group. Calorie-restricted diet therapy is more effective in reducing plasma LDL cholesterol in type 2 diabetic patients with the apoE4 allele. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- To examine usual marine ω-3 fatty acid (mO-3FA) intake in individuals with diabetes; its association with adiposity, lipid, and glucose control; and its changes with behavioral lifestyle intervention for weight loss. RESEARCH DESIGN AND METHODS-- Cross-sectional and 1-year longitudinal analyses were performed on 2,397 Look AHEAD (Action for Health in Diabetes) participants. Look AHEAD is a cardiovascular outcome trial evaluating the effects of intensive lifestyle intervention for weight loss in overweight/obese subjects with type 2 diabetes. RESULTS -- Baseline mO-3FA intake was 162 ± 138 mg/day. It was inversely associated with triglycerides (β = -0.41, P < 0.001) and weakly with HDL (β = 4.14, P = 0.050), after multiple covariate adjustment. One-year mO-3FA and fried/sandwich fish intake decreased with intensive lifestyle intervention (P < 0.001). CONCLUSIONS -- mO-3FA intake in Look AHEAD participants was low but associated favorably with lipids. These results encourage investigation on the potential benefits of increasing mO-3FA intake in lifestyle interventions for weight loss in individuals with diabetes. [ABSTRACT FROM AUTHOR]

OBJECTIVE -- Subjects with the metabolic syndrome have reduced HDL cholesterol concentration and altered metabolism of high-density lipoprotein (Lp)A-I and LpA-I:A-II particles. In the metabolic syndrome, fenofibrate and atorvastatin may have differential effects on HDL particle kinetics. RESEARCH DESIGN AND METHODS -- Eleven men with metabolic syndrome were studied in a randomized, double-blind, crossover trial of 5-week intervention periods with placebo, fenofibrate (200 mg/day), and atorvastatin (40 mg/day). LpA-I and LpA-I:A-II kinetics were examined using stable isotopic techniques and compartmental modeling. RESULTS-- Compared with placebo, fenofibrate significantly increased the production of both LpA-I:A-II (30% increase; P < 0.001) and apoA-II (43% increase; P < 0.001), accounting for significant increases of their corresponding plasma concentrations (10 and 23% increases, respectively), but it did not alter LpA-I kinetics or concentration. Atorvastatin did not significantly alter HDL concentration or the kinetics of HDL particles. CONCLUSIONS -- In the metabolic syndrome, fenofibrate, but not atorvastatin, influences HDL metabolism by increasing the transport of LpA-I:A-II particles. [ABSTRACT FROM AUTHOR]

The article focuses on a study that examined whether the preβ1-high density lipoprotein (HDL) concentration is elevated in type 2 diabetic patients and whether elevated preβ1-HDL concentration is a predictor of carotid atherosclerosis. It found that the absolute preβ1-HDL concentration was associated with carotid atherosclerosis but not with glycemic control or other HDL markers.