Effects of total fibre or resistant starch-rich diets within lifestyle intervention in obese prediabetic adults.

PURPOSE: Starting from the evidence-based health benefits that resistant starch (RS) shows when added to the diet, our aim in this study was to evaluate the effects of increased fibre intake with two different levels of RS coming from regular daily consumed foods on normalization of glycaemia within lifestyle intervention in the population with risk factors for developing diabetes. METHODS: Study included 47 overweight and obese men and women with disordered glucoregulation and dyslipidaemia, aged between 45-74, divided into RS and Fibre group. Participants were subjected to the lifestyle and dietary intervention with low-fat and high-fibre (>25 g/day) diet for 12 months and were offered two different dietary advices aimed at increasing total fibre intake in Fibre group and at increasing RS intake in RS group. RESULTS: The intake of macronutrients and total fibre was similar between groups at the end of the study, but achieved RS intake was two times higher in the RS group. Decrease in total cholesterol and non-HDL-cholesterol was more pronounced in RS group in comparison with Fibre group (p = 0.010, p = 0.031, respectively), whereas in Fibre group, a more pronounced effect on glucoregulation was observed: significant fall in glycaemia after 2-h oral glucose tolerance test (7.93 vs 6.96 mmol/L, p = 0.034). CONCLUSION: At the end of the study, RS-rich diet failed to affect glycaemic control in prediabetic obese individuals in contrast to the regular fibre-rich diet, which indicated that fibre profile could be an important determinant of the effect of dietary intervention.

Increased Oxidized High-Density Lipoprotein/High-Density Lipoprotein-Cholesterol Ratio as a Potential Indicator of Disturbed Metabolic Health in Overweight and Obese Individuals.

BACKGROUND: We evaluated the qualitative characteristics of high-density lipoprotein (HDL) particles in metabolically healthy and unhealthy overweight and obese subjects. METHODS: The study involved 115 subject individuals classified as metabolically healthy and unhealthy, as in overweight and obese groups. Commercial enzyme-linked immunosorbent assay (ELISA) kits were used to measure oxidized HDL (OxHDL) and serum amyloid A (SAA) concentrations. Lipoprotein subfractions were separated using nondenaturing gradient gel electrophoresis. RESULTS: An independent association was shown between increased OxHDL/HDL-cholesterol ratio and the occurrence of metabolically unhealthy phenotype in the overweight and obese groups. The OxHDL/HDL-cholesterol ratio showed excellent and acceptable diagnostic accuracy in determination of metabolic health phenotypes (overweight group, AUC = 0.881; obese group, AUC = 0.765). Accumulation of smaller HDL particles in metabolically unhealthy subjects was verified by lipoprotein subfraction analysis. SAA concentrations did not differ significantly between phenotypes. CONCLUSIONS: Increased OxHDL/HDL-cholesterol ratio may be a potential indicator of disturbed metabolic health in overweight and obese individuals.

Dietary fat intake as risk factor for the development of diabetes: multinational, multicenter study of the Mediterranean Group for the Study of Diabetes (MGSD).

OBJECTIVE: To investigate the role of dietary factors in the development of type 2 diabetes. RESEARCH DESIGN AND METHODS: In the context of the Multinational MGSD Nutrition Study, three groups of subjects were studied: 204 subjects with recently diagnosed diabetes (RDM), 42 subjects with undiagnosed diabetes (UDM) (American Diabetes Association criteria-fasting plasma glucose [FPG] > or =126 mg/dl), and 55 subjects with impaired fasting glucose (IFG) (FPG > or =110 and <126 mg/dl). Each group was compared with a control group of nondiabetic subjects, matched one by one for center, sex, age, and BMI. Nutritional habits were evaluated by a dietary history method, validated against the 3-day diet diary. In RDM, the questionnaire referred to the nutritional habits before the diagnosis of diabetes. Demographic data were collected, and anthropometrical and biochemical measurements were taken. RESULTS: Compared with control subjects, RDM more frequently had a family history of diabetes (49.0 vs. 14.2%; P < 0.001), exercised less (exercise index 53.5 vs. 64.4; P < 0.01), and more frequently had sedentary professions (47.5 vs. 27.4%; P < 0.001). Carbohydrates contributed less to their energy intake (53.5 vs. 55.1%; P < 0.05), whereas total fat (30.2 +/- 0.5 vs. 27.8 +/- 0.5%; P < 0.001) and animal fat (12.2 +/- 0.3 vs. 10.8 +/- 0.3%; P < 0.01) contributed more and the plant-to-animal fat ratio was lower (1.5 +/- 0.1 vs. 1.8 +/- 0.1; P < 0.01). UDM more frequently had a family history of diabetes (38.1 vs. 19.0%; P < 0.05) and sedentary professions (58.5 vs. 34.1%; P < 0.05), carbohydrates contributed less to their energy intake (47.6 +/- 1.7 vs. 52.8 +/- 1.4%; P < 0.05), total fat (34.7 +/- 1.5 vs. 30.4 +/- 1.2%; P < 0.05) and animal fat (14.2 +/- 0.9 vs. 10.6 +/- 0.7%; P < 0.05) contributed more, and the plant-to-animal fat ratio was lower (1.6 +/- 0.2 vs. 2.3 +/- 0.4; P < 0.05). IFG differed only in the prevalence of family history of diabetes (32.7 vs. 16.4%; P < 0.05). CONCLUSIONS: Our data support the view that increased animal fat intake is associated with the presence of diabetes.

Characterisation of dietary fibre components in cereals and legumes used in Serbian diet.

The typical Serbian diet is characterised by high intake of cereal products and also legumes are often used. The content of total fibre as well as certain fibre fractions was determined in cereals, cereal products, and cooked legumes. The content of total fibre in cooked cereals and cereal products ranged from 2.5 to 20.8 g/100 g, and in cooked legumes from 14.0 to 24.5 g/100 g (on dry matter basis). Distribution of analysed fibre fractions and their quantities differed significantly depending on food groups. Fructans and arabinoxylans were the most significant fibre fractions in rye flakes, and ß-glucan in oat flakes, cellulose and resistant starch were present in significant amounts in peas and kidney beans. When the size of regular food portions was taken into consideration, the best sources of total dietary fibre were peas and kidney beans (more than 11 g/serving). The same foods were the best sources of cellulose (4.98 and 3.56 g/serving) and resistant starch (3.90 and 2.83 g/serving). High intake of arabinoxylans and fructans could be accomplished with cooked wheat (3.20 g and 1.60 g/serving, respectively). Oat (1.39 g/serving) and barley flakes (1.30 g/serving) can be recommended as the best sources of ß-glucan.