RESUMO
Dietary fibre is a generic term describing non-absorbed plant carbohydrates and small amounts of associated non-carbohydrate components. The main contributors of fibre to the diet are the cell walls of plant tissues, which are supramolecular polymer networks containing variable proportions of cellulose, hemicelluloses, pectic substances, and non-carbohydrate components, such as lignin. Other contributors of fibre are the intracellular storage oligosaccharides, such as fructans. A distinction needs to be made between intrinsic sources of dietary fibre and purified forms of fibre, given that the three-dimensional matrix of the plant cell wall confers benefits beyond fibre isolates. Movement through the digestive tract modifies the cell wall structure and may affect the interactions with the colonic microbes (e.g., small intestinally non-absorbed carbohydrates are broken down by bacteria to short-chain fatty acids, absorbed by colonocytes). These aspects, combined with the fibre associated components (e.g., micronutrients, polyphenols, phytosterols, and phytoestrogens), may contribute to the health outcomes seen with the consumption of dietary fibre. Therefore, where possible, processing should minimise the degradation of the plant cell wall structures to preserve some of its benefits. Food labelling should include dietary fibre values and distinguish between intrinsic and added fibre. Labelling may also help achieve the recommended intake of 14 g/1000 kcal/day.
Assuntos
Consenso , Fibras na Dieta/normas , Qualidade dos Alimentos , Rotulagem de Alimentos , Humanos , Internacionalidade , OrganizaçõesRESUMO
Type 2 diabetes mellitus (T2DM) is characterised by chronic low-grade inflammation, recently referred to as 'metaflammation', a relevant factor contributing to the development of both diabetes and its complications. Nonetheless, 'canonical' anti-inflammatory drugs do not yield satisfactory results in terms of prevention of diabetes progression and of cardiovascular events, suggesting that the causal mechanisms fostering metaflammation deserve further research to identify new druggable targets. Metaflammation resembles ageing-induced low-grade inflammation, previously referred to as inflammageing, in terms of clinical presentation and the molecular profile, pointing to a common aetiology for both conditions. Along with the mechanisms proposed to fuel inflammageing, here we dissect a plethora of pathological cascades triggered by gluco- and lipotoxicity, converging on candidate phenomena possibly explaining the enduring pro-inflammatory program observed in diabetic tissues, i.e. persistent immune-system stimulation, accumulation of senescent cells, epigenetic rearrangements, and alterations in microbiota composition. We discuss the possibility of harnessing these recent discoveries in future therapies for T2DM. Moreover, we review recent evidence regarding the ability of diets and physical exercise to modulate selected inflammatory pathways relevant for the diabetic pathology. Finally, we examine the latest findings showing putative anti-inflammatory mechanisms of anti-hyperglycaemic agents with proven efficacy against T2DM-induced cardiovascular complications, in order to gain insights into quickly translatable therapeutic approaches.
Assuntos
Senescência Celular/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/terapia , Dietoterapia/métodos , Exercício Físico/fisiologia , Animais , Sistema Cardiovascular/imunologia , Sistema Cardiovascular/metabolismo , Diabetes Mellitus Tipo 2/imunologia , Dietoterapia/tendências , Humanos , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/terapia , Estresse Oxidativo/fisiologiaAssuntos
Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus Tipo 2/tratamento farmacológico , Ácidos Graxos Ômega-3/uso terapêutico , Intolerância à Glucose/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Insulina de Ação Prolongada/uso terapêutico , Feminino , Humanos , MasculinoRESUMO
BACKGROUND: Findings from animal models suggest that selenium supplementation improves glucose metabolism. OBJECTIVE: To examine the effect of long-term selenium supplementation on the incidence of type 2 diabetes. DESIGN: Secondary analysis of a randomized, double-blind, placebo-controlled trial. SETTING: Areas of low selenium consumption of the eastern United States. PATIENTS: 1202 persons seen in dermatology clinics who did not have type 2 diabetes at baseline. INTERVENTION: Oral administration of selenium, 200 microg/d, or placebo. MEASUREMENTS: Incidence of type 2 diabetes. RESULTS: During an average follow-up of 7.7 years (SD, 2.7), type 2 diabetes developed in 58 selenium recipients and 39 placebo recipients (incidence, 12.6 cases per 1000 person-years vs. 8.4 cases per 1000 person-years, respectively; hazard ratio, 1.55 [95% CI, 1.03 to 2.33]). The lack of benefit of selenium supplementation on the incidence of type 2 diabetes persisted in analyses stratified by age, sex, body mass index, and smoking status. An exposure-response gradient was found across tertiles of baseline plasma selenium level, with a statistically significantly increased risk for type 2 diabetes in the highest tertile of baseline plasma selenium level (hazard ratio, 2.70 [CI, 1.30 to 5.61]). LIMITATIONS: Diabetes was a secondary outcome in the parent trial. Diagnoses of diabetes were self-reported but were validated in most participants. The sample was mostly older and white. CONCLUSIONS: Selenium supplementation does not seem to prevent type 2 diabetes, and it may increase risk for the disease. Click here for related information on selenium.
Assuntos
Antioxidantes/administração & dosagem , Diabetes Mellitus Tipo 2/prevenção & controle , Suplementos Nutricionais , Selênio/administração & dosagem , Idoso , Antioxidantes/efeitos adversos , Antioxidantes/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Selênio/efeitos adversos , Selênio/sangue , Fatores de Tempo , Estados UnidosRESUMO
Reducing the incidence of coronary heart disease with diet is possible. The main dietary strategies include adequate omega-3 fatty acids intake, reduction of saturated and trans-fats, and consumption of a diet high in fruits, vegetables, nuts, and whole grains and low in refined grains. Each of these strategies may be associated with lower generation of inflammation. This review examines the epidemiologic and clinical evidence concerning diet and inflammation. Dietary patterns high in refined starches, sugar, and saturated and trans-fatty acids, poor in natural antioxidants and fiber from fruits, vegetables, and whole grains, and poor in omega-3 fatty acids may cause an activation of the innate immune system, most likely by an excessive production of proinflammatory cytokines associated with a reduced production of anti-inflammatory cytokines. The whole diet approach seems particularly promising to reduce the inflammation associated with the metabolic syndrome. The choice of healthy sources of carbohydrate, fat, and protein, associated with regular physical activity and avoidance of smoking, is critical to fighting the war against chronic disease. Western dietary patterns warm up inflammation, while prudent dietary patterns cool it down.
Assuntos
Dieta , Gorduras na Dieta , Inflamação/fisiopatologia , Síndrome Metabólica/dietoterapia , Síndrome Metabólica/prevenção & controle , Antioxidantes , Citocinas , Dieta Mediterrânea , Fibras na Dieta , Ácidos Graxos Ômega-3 , Humanos , Síndrome Metabólica/fisiopatologiaRESUMO
OBJECTIVE: The aim of this systematic review was to determine the benefits of nutritional support in patients with type 1 or type 2 diabetes. RESEARCH DESIGN AND METHODS: Studies utilizing an enteral nutritional support intervention (oral supplements or tube feeding) were identified using electronic databases and bibliography searches. Comparisons of interest were nutritional support versus routine care and standard versus diabetes-specific formulas (containing high proportions of monounsaturated fatty acids, fructose, and fiber). Outcomes of interest were measures of glycemia and lipid status, medication requirements, nutritional status, quality of life, complications, and mortality. Meta-analyses were performed where possible. RESULTS: A total of 23 studies (comprising 784 patients) of oral supplements (16 studies) and tube feeding (7 studies) were included in the review, and the majority compared diabetes-specific with standard formulas. Compared with standard formulas, diabetes-specific formulas significantly reduced postprandial rise in blood glucose (by 1.03 mmol/l [95% CI 0.58-1.47]; six randomized controlled trials [RCTs]), peak blood glucose concentration (by 1.59 mmol/l [86-2.32]; two RCTs), and glucose area under curve (by 7.96 mmol.l(-1).min(-1) [2.25-13.66]; four RCTs, i.e., by 35%) with no significant effect on HDL, total cholesterol, or triglyceride concentrations. In addition, individual studies reported a reduced requirement for insulin (26-71% lower) and fewer complications with diabetes-specific compared with standard nutritional formulas. CONCLUSIONS: This systematic review shows that short- and long-term use of diabetes-specific formulas as oral supplements and tube feeds are associated with improved glycemic control compared with standard formulas. If such nutritional support is given long term, this may have implications for reducing chronic complications of diabetes, such as cardiovascular events.