Jussara Carnevale de Almeida

Fiber intake and glycemic control in patients with type 2 diabetes mellitus: a systematic review with meta-analysis of randomized controlled trials

This systematic review with meta-analysis of randomized controlled trials (RCT) aimed to analyze the effect of fiber intake on glycemic control in patients with type 2 diabetes. Databases were searched up to November 2012 using the following medical subject headings: diabetes, fiber, and randomized controlled trial. Absolute changes in glycated hemoglobin and fasting plasma glucose were reported as differences between baseline and end-of-study measures. Pooled estimates were obtained using random-effects models. Of the 22,046 articles initially identified, 11 (13 comparisons; range of duration, 8-24 weeks) fulfilled the inclusion criteria, providing data from 605 patients. High-fiber diets, including diets with foods rich in fiber (up to 42.5 g/day; four studies) or supplements containing soluble fiber (up to 15.0 g/day; nine studies), reduced absolute values of glycated hemoglobin by 0.55% (95% CI -0.96 to -0.13) and fasting plasma glucose by 9.97 mg/dL (95% CI -18.16 to -1.78). In conclusion, increased fiber intake improved glycemic control, indicating it should be considered as an adjunctive tool in the treatment of patients with type 2 diabetes.

Effect of diet on adiponectin levels in blood

Dietary management has been considered an alternative means of modulating adiponectin levels. The purpose of this review is to examine the scientific evidence regarding the effect of diet on adiponectin levels in blood. Clinical trials were selected from Medline until April 2010 using the following MeSH terms: adipokines OR adiponectin AND diet OR lifestyle. A total of 220 articles were identified in the initial search, and 52 studies utilizing three different methods of dietary management were included in the present review: low-calorie diets (n = 9 studies), modification of diet composition (n = 33), and diet plus exercise (n = 10). Daily intake of fish or omega-3 supplementation increased adiponectin levels by 14-60%. Weight loss achieved with a low-calorie diet plus exercise increased adiponectin levels in the range of 18-48%. A 60-115% increase in adiponectin levels was obtained with fiber supplementation. In conclusion, dietary management can be an effective therapeutic means of increasing adiponectin levels. Studies investigating different forms of adiponectin and changes in the types of adipose tissue are necessary in order to elucidate the mechanisms involved in the modulation of adiponectin levels.

Intake of soluble fibers has a protective role for the presence of metabolic syndrome in patients with type 2 diabetes.

Background/Objectives:Dietary factors have been associated with metabolic syndrome (MS) in healthy individuals and specific ethnic groups. To evaluate possible associations of usual dietary factors with the presence of MS in patients with type 2 diabetes mellitus (DM).Subjects/Methods:In this cross-sectional study, 214 patients with type 2 DM without dietary counseling during previous 6 months were studied. After clinical and laboratory examinations, dietary intake was evaluated by 3-day weighed-diet records, whose reliability was confirmed by 24-h urinary nitrogen output. The presence of MS was defined according to International Diabetes Federation.Results:Patients with MS (n=174) had a lower intake of total (16.7±6.2 vs 19.5±6.5 g day−1; P=0.010) and soluble fibers (5.3±1.8 vs 6.0±2.7 g day−1; P=0.011) than patients without MS. In multiple logistic regression models, adjusted for gender and DM duration, variables associated with MS were soluble fibers (OR=0.86; 95% CI=0.74–0.98; P=0.046), soluble fibers from whole-grain foods (OR=0.43; 95% CI=0.25–0.76; P=0.002) and soluble fibers from fruits (OR=0.76; 95% CI=0.62–0.95; P=0.017). Whole-grain and fruits were the foods negatively associated with MS.Conclusions:The intake of soluble fibers, particularly from whole-grain foods and fruits, may have a protective role for the presence of MS in this selected sample of patients with type 2 DM.

Improvement of the metabolic syndrome profile by soluble fibre - guar gum - in patients with type 2 diabetes: a randomised clinical trial.

A diet rich in fibre seems to protect against the metabolic syndrome (MetS), but there is scarce information about the role of fibre intake in patients with the MetS and diabetes. The aim of the present study was to evaluate the effects of soluble fibre from partially hydrolysed guar gum (PHGG) on the MetS and cardiovascular risk factors in patients with type 2 diabetes. In the present randomised controlled clinical trial, forty-four patients with type 2 diabetes (males 38·6 %, age 62 (SD 9) years, diabetes duration 14·2 (SD 9·6) years) and the MetS underwent clinical, laboratory and dietary evaluations at baseline, 4 and 6 weeks. All patients followed their usual diet and the intervention group (n 23) received an additional 10 g/d of PHGG. In the intervention group, waist circumference (WC), glycated Hb (HbA1c), 24 h urinary albumin excretion (UAE) and serum trans-fatty acids (FA) were reduced in comparison with baseline after 4 and 6 weeks: WC 103·5 (SD 9·5) to 102·1 (SD 10) to 102·3 (SD 9·7) cm; HbA1c 6·88 (SD 0·99) to 6·64 (SD 0·94) to 6·57 (SD 0·84) %; 24 h UAE 6·8 (interquartile range 3·0-17·5) to 4·5 (interquartile range 3·0-10·5) to 6·2 (interquartile range 3·0-9·5) mg; trans-FA 71 (interquartile range 46-137) to 67 (interquartile range 48-98) to 57 (interquartile range 30-110) mg/l (P< 0·05 for all). The only change in the control group was weight reduction: 77·0 (SD 13·5) to 76·2 (SD 13·3) to 76·1 (SD 13·4) kg (P= 0·005). Other MetS components (blood pressure, TAG, HDL-cholesterol, fasting plasma glucose), total and LDL-cholesterol, C-reactive protein and endothelin-1 did not change in either group. In patients with type 2 diabetes and the MetS, the addition of PHGG to the usual diet improved cardiovascular and metabolic profiles by reducing WC, HbA1c, UAE and trans-FA.

Sources of Protein and Polyunsaturated Fatty Acids of the Diet and Microalbuminuria in Type 2 Diabetes Mellitus

Background: Albuminuria excretion rate above the reference range and below albustix positive proteinuria (20–199 μg/min) is known as microalbuminuria and has been associated with an increased risk of death and progression to renal failure. Besides hyperglicemia and high blood pressure levels, dietary factors can also influence albuminuria. Objective: To evaluate possible associations of dietary components (macronutrients and selected foods) with microalbuminuria in type 2 diabetic patients. Methods: In this cross-sectional study, 119 normoalbuminuric [NORMO; 24-h urinary albumin excretion (UAE) < 20 μg/min; immunoturbidimetry] and 62 microalbuminuric (MICRO; UAE 20–199 μg/min) type 2 diabetic patients, attending the Endocrine Division, Hospital de Clínicas de Porto Alegre (Brazil), without previous dietary counseling, underwent 3-day weighed-diet records, and clinical and laboratory evaluation. Results: MICRO patients consumed more protein (20.5 ± 4.4 vs. 19.0 ± 3.5% of total energy; p = 0.01) with a higher intake from animal sources (14.5 ± 4.7 vs. 12.9 ± 3.8% of total energy; p = 0.015) than NORMO patients. The intakes of PUFAs (8.6 ± 2.9 vs. 9.7 ± 3.3% of total energy; p < 0.03), PUFAs from vegetable sources (7.3 ± 3.4 vs. 8.6 ± 3.7% of total energy; p = 0.029), plant oils [0.2 (0.1–0.6) vs. 0.3 (0.1–0.9) mg/kg weight; p = 0.02] and margarines [3.3 (0–75.7) vs. 7.0 (0–51.7) g/day; p = 0.01] were lower in MICRO than in NORMO. In multivariate logistic regression models, adjusted for age, gender, presence of hypertension and fasting plasma glucose, intake of total protein (% of total energy; OR 1.104; 95% CI 1.008–1.208; p = 0.032) was positively associated with microalbuminuria. The intakes of total PUFAs (% of total energy; OR 0.855; 95%CI 0.762–0.961; p = 0.008), PUFAs from vegetable sources (% of total energy; OR 0.874; 95%CI 0.787–0.971; p = 0.012) and plant oils (mg/kg weight; OR 0.036; 95% CI 0.003–0.522; p = 0.015) were negatively associated with microalbuminuria. Conclusions: In type 2 diabetic patients, the high intake of protein and the low intake of PUFAs, particularly from plant oils, were associated with the presence of microalbuminuria. Reducing protein intake from animal sources and increasing the intake of lipids from vegetable origin might-reduce the risk of microalbuminuria.

The role of Dietary Approaches to Stop Hypertension (DASH) diet food groups in blood pressure in type 2 diabetes

The role of each Dietary Approaches to Stop Hypertension (DASH) diet component in blood pressure (BP) of patients with diabetes is still uncertain. The aim of the present study was to evaluate possible associations of the recommended food groups of the DASH diet eating plan with BP values in patients with type 2 diabetes. In the present cross-sectional study, 225 patients with type 2 diabetes (age 61·1 (SD 10·4) years; diabetes duration 13·1 (SD 9·1) years; males 48·4 %; BMI 28·5 (SD 4·3) kg/m(2); HbA1c 7·1 (SD 1·3) %; systolic BP 136·7 (SD 20·0) mmHg; diastolic BP 78·4 (SD 11·8) mmHg) without dietary counselling during the previous 6 months had their dietary intake assessed by 3 d weighed-diet records. Patients were divided into two groups according to BP tertiles: LOW BP (first tertile) and HIGH BP (second plus third tertiles). Multivariate logistic regression models demonstrated that the daily intake of 80 g of fruits per 4184 kJ (1000 kcal) (OR 0·781; 95 % CI 0·617, 0·987; P = 0·039) or 50 g of vegetables per 4184 kJ (1000 kcal) (OR 0·781; 95 % CI 0·618, 0·988; P = 0·040) reduced the chance of the presence of HIGH mean BP (MBP ≥ 92 mmHg) by 22 % each, adjusted for possible confounders. In conclusion, fruit and vegetables were the food groups of the DASH diet associated with reduced BP values in patients with type 2 diabetes, and their consumption might play a protective role against increased BP values.

Endothelial dysfunction and serum fatty acid composition in patients with type 2 diabetes mellitus

The aim of this study was to evaluate the possible association between serum fatty acids composition and endothelial dysfunction in patients with type 2 diabetes mellitus. A cross-sectional study was conducted with 125 normo- or microalbuminuric type 2 diabetes mellitus patients with serum creatinine <1.5 mg/dL. Serum fatty acids composition (gas chromatography), serum levels of endothelin-1 (ET-1) (enzyme-linked immunosorbent assay), fibrinogen, serum C-reactive protein, lipids, homeostasis model assessment resistance index (HOMA-R), and 24-hour urinary albumin excretion rate were measured. Serum levels of ET-1 were positively correlated with saturated fatty acids (r = 0.257, P = .025) and negatively correlated with polyunsaturated fatty acids (PUFAs) (r = -0.319, P = .005). Serum ET-1 levels were also positively correlated with systolic blood pressure, waist circumference, total cholesterol levels, triglycerides, and HOMA-R. In multiple linear regression models, only saturated fatty acids (R(2) = 0.317, P = .002) or PUFAs (R(2) = 0.314, P = .001) remained associated with ET-1 levels. Models were adjusted for systolic blood pressure, HOMA-R, waist circumference, triglycerides, body mass index, and smoking habit. The serum total PUFA levels showed an inverse correlation with urinary albumin excretion rate (r = -0.248, P = .012). In conclusion, in type 2 diabetes mellitus patients, the serum fatty acids composition was independently related to endothelial function evaluated by serum ET-1. Saturated fatty acids were associated with endothelial dysfunction (high levels of ET-1), whereas PUFAs had a protective role in endothelial function.

Antioxidant micronutrients and cardiovascular risk in patients with diabetes: a systematic review.

Background Inverse associations between micronutrient intake and cardiovascular outcomes have been previously shown, but did not focus on diabetic patients. Objective To systematically review the role of micronutrients in the development/presence of cardiovascular outcomes in patients with diabetes. Methods We searched Medline, Embase, and Scopus (January/1949-March/2012) for observational studies that evaluated micronutrients and cardiovascular outcomes in patients with diabetes, and then selected and extracted the data (two independent reviewers). Results From the 15 658 studies identified, five were included, comprising three case-control and two cohorts, with a follow-up of 7-15 years. A meta-analysis was not performed due to the different antioxidant micronutrients (types and measurement methods) and outcomes evaluated. The micronutrients assessed were vitamin C intake in diet and/ or supplementation, chromium and selenium in toenail samples, and α-tocopherol and zinc in serum levels. Intake of > 300 mg of vitamin C through supplementation was associated with increased risk of cardiovascular disease, coronary artery disease (CAD), and stroke (RR 1.69-2.37). High levels of α-tocopherol in serum were associated with 30% lower CAD risk in another study (HR 0.71; 95%CI 0.53-0.94). Among minerals (zinc, selenium, and chromium), an inverse association between zinc and CAD was observed; levels lower than 14.1 μmol/L were associated with an increased risk for CAD (RR 1.70; 95%CI 1.21-2.38). Conclusion The information available on this issue is scarce. Further prospective studies are needed to elucidate the role of these nutrients in the cardiovascular risk of patients with diabetes.

Protein intake estimated by weighed diet records in patients with type 2 diabetes: misreporting and intra-individual variability using 24-hour nitrogen output as criterion standard.

In patients with type 2 diabetes mellitus (DM), the factors associated with under- or overreporting of protein intake in nutrition assessment tools, as well as the variability of diet records, have not been fully established. The aim of this cross-sectional study was to evaluate factors associated with under- or overreporting of protein intake and its variability in patients with type 2 DM. Protein intake was estimated in 205 patients (aged 59.8+/-9.6 years) using 3-day weighed diet records and 24-hour nitrogen output (criterion standard). Twenty-three patients repeated the 3-day weighed diet records three times. Clinical, nutrition, and lifestyle evaluations were performed. Coefficients of variation were calculated for protein intake. Factors associated with under- and overreporting were assessed using multivariate logistic regression models. Coefficients of variation for protein intake estimated by weighed diet records or nitrogen output were similar (11.9% vs 11.3%; P>0.05). Using Beatons formula, a difference of 16.5% in protein intake between two 3-day weighed diet records was acceptable. The lowest A1c test tertile (< or =6.9%) was associated with protein intake underreporting (odds ratio [OR]=0.40; 95% confidence interval [CI]=0.16 to 0.99; P=0.046] after adjustment for sex, age, employment status, and living alone. Male sex (OR=6.66; 95% CI: 2.08 to 22.07; P=0.002), A1c test (OR=1.29; 95% CI: 1.02 to 1.64; P=0.036), and body mass index (OR=0.89; 95% CI: 0.80 to 0.994; P=0.039), adjusted for physical and employment status, education, and preparing ones own meals, were associated with overreporting. In conclusion, in patients with type 2 DM, a difference >16.5% in protein intake between two 3-day weighed diet records should be interpreted as a true discrepancy. Poor glucose control and male sex increase the chance of inaccurate 3-day weighed diet records.

Parallel Down-Regulation of FOXO1, PPARγ and Adiponectin mRNA Expression in Visceral Adipose Tissue of Class III Obese Individuals

Objective: Adipose tissue is responsible for secretion of several cytokines that mediate systemic effects on obesity and insulin resistance. Subcutaneous abdominal adipose tissue (SAT) and visceral adipose tissue (VAT) are metabolically different and have differences in their gene expression profile. Our study evaluated the expression of adiponectin, FOXO1, PPARγ, and SIRT1 in VAT and SAT of non-obese and class III obese subjects. Methods: The adipose tissue samples were obtained by surgery. Reverse transcripts of studied genes were determined by quantitative real-time polymerase chain reaction (qRT-PCR). Results: Comparing the different lipid depots, adiponectin expression was lower only in VAT of obese individuals (p = 0.043); FOXO1 and PPARγ levels were decreased in VAT of both groups. When non-obese and obese were compared, only adiponectin expression was lower in SAT and in VAT of obese subjects (p = 0.004 and p = 0.002, respectively). No difference was found with regard to SIRT1 levels in VAT or SAT in both groups. FOXO1 expression in SAT of obese subjects had a negative correlation with age (r = –0.683; p = 0.029) and triglyceride serum levels (r = –0.794; p = 0.006). Conclusion: The decrease mRNA expression of this genes in VAT, responsible for central adiposity, may be associated with an increased risk of obesity and co-morbidities.