Fortifying a meal with oyster mushroom powder beneficially affects postprandial glucagon-like peptide-1, non-esterified free fatty acids and hunger sensation in adults with impaired glucose tolerance: a double-blind randomized controlled crossover trial.

PURPOSE: Impaired glucose tolerance (IGT) is a pathophysiological condition characterized by insulin resistance with known metabolic consequences such as postprandial hyperglycemia and hypertriglyceridemia. We hypothesized that fortifying a meal with mushrooms rich in ß-glucans may diminish glucose and triglyceride responses by improving postprandial gastrointestinal hormone release. METHODS: In a randomized controlled crossover study, 22 subjects with IGT ingested a meal either enriched with 20 g powder (8.1 g ß-glucans) of oven-dried Pleurotus ostreatus (enriched meal, EN) or without enrichment (control meal, CON). Blood was collected before and repeatedly within 4 h after the meal to determine AUC of glucose (primary outcome), insulin, triglycerides, non-esterified free fatty acids (NEFAs), glucagon-like peptide-1 (GLP-1), gastric inhibitory polypeptide (GIP) and ghrelin. Appetite sensations (hunger, satiety, fullness, and desire to eat) were assessed before and after meal consumption by visual analog scales. RESULTS: Postprandial glucose, insulin, triglycerides, GIP and ghrelin concentrations as well as the corresponding AUCs did not differ between EN and CON. NEFAs-AUC was 14% lower (P = 0.026) and GLP-1-AUC 17% higher (P = 0.001) after EN compared to CON. Appetite ratings did not differ between treatments, except for hunger (AUC 22% lower after EN vs. CON; P = 0.031). CONCLUSION: The observed immediate postprandial metabolic changes indicate that an easily manageable fortification of a single meal with powder from dried oyster mushrooms as ß-glucan source may improve postprandial metabolism. If the effect is preserved long term, this measure can diminish the risk for further development of overweight/obesity and type 2 diabetes in subjects with IGT. CLINICAL TRIAL REGISTRATION: German Clinical Trial Register on 09/08/2018; trial-ID: DRKS00015244.

Impact of a Usual Serving Size of Flavanol-Rich Cocoa Powder Ingested with a Diabetic-Suitable Meal on Postprandial Cardiometabolic Parameters in Type 2 Diabetics-A Randomized, Placebo-Controlled, Double-Blind Crossover Study.

Randomized controlled trials indicate that flavanol-rich cocoa intake may improve postprandial glucose and lipid metabolism in patients with type 2 diabetes (T2D), based on studies with meals that impose a strong metabolic load. Hence, the aim of the present study was to investigate whether flavanol-rich cocoa powder ingested as part of a diabetic-suitable meal may beneficially affect glucose, lipid metabolism, and blood pressure (BP) in patients with T2D. Twelve adults with T2D, overweight/obesity, and hypertension ingested capsules with 2.5 g of flavanol-rich cocoa or microcrystalline cellulose with a diabetic-suitable breakfast in a randomized, placebo-controlled, double-blind crossover study. BP was measured and blood samples were taken before, 2 and 4 h after breakfast and capsule intake. Cocoa treatment did not affect glucose, insulin, homeostasis model assessment for insulin resistance (HOMA-IR), triglycerides, total cholesterol, low density lipoprotein-cholesterol, high density lipoprotein-cholesterol, and BP. For glucose, insulin and HOMA-IR, only effects by time were observed after both treatments. Thus, 2.5 g of flavanol-rich cocoa powder ingested as part of a diabetic-suitable meal does not seem to affect postprandial glucose and lipid metabolism and BP in stably-treated diabetics. Nevertheless, future studies with close-meshed investigations are desirable, providing realistic amounts of cocoa together with realistic meals rich in carbohydrates to subjects with T2D or metabolic syndrome, which do not afford pharmacological treatment.

A nutritive dose of pure (-)-epicatechin does not beneficially affect increased cardiometabolic risk factors in overweight-to-obese adults-a randomized, placebo-controlled, double-blind crossover study.

Background: Regular cocoa consumption has been shown to reduce blood pressure, improve lipid profiles, and increase insulin sensitivity and flow-mediated dilatation in healthy adults. It is assumed that these effects can be attributed to polyphenolic cocoa ingredients such as flavanols, especially to (-)-epicatechin. Nutritive intervention studies to prove this hypothesis are scarce. Objective: We aimed to evaluate whether regular consumption of 25 mg of pure (-)-epicatechin can affect increased cardiometabolic risk factors [blood pressure, glucose and lipid metabolism, low-density lipoprotein (LDL) oxidation] in overweight-to-obese subjects. Design: Forty-eight overweight or obese nonsmokers [body mass index (kg/m2) ≥25.0, ages 20-65 y] with clear signs of metabolic syndrome (blood pressure ≥130/85 mm Hg, glucose >5.55 mmol/L, or triglycerides >1.69 mmol/L or cholesterol >5.2 mmol/L in fasting blood) and without chronic diseases were included in a randomized, placebo-controlled, double-blind crossover study. Participants ingested daily 25 mg (-)-epicatechin (encapsulated) or placebo for 2-wk in random order (2-wk washout). After an overnight fast, blood pressure was monitored and blood samples were collected before and after both treatments. Anthropometric data were determined at each visit. Dietary intake was assessed by 3-d food records during both treatments and during run-in and washout phase. Results: Supplementation of pure (-)-epicatechin did not significantly affect blood pressure, glucose, insulin, homeostasis model assessment of insulin resistance, triglycerides, or total, LDL, or HDL cholesterol. Oxidized LDL, vitamins C and E, and ß-carotene in plasma were not modulated. Body weight, fat mass, fat distribution, and the intake of energy, nutrients, and (-)-epicatechin from food remained stable throughout the study. Conclusions: Daily intake of 25 mg of pure (-)-epicatechin for 2 wk does not reduce cardiometabolic risk factors in overweight-to-obese adults. Thus, the hypothesis that the cardioprotective effects of regular cocoa consumption are exclusively ascribed to (-)-epicatechin should be reconsidered. The study was registered at the German Clinical Trial Register as DRKS-ID: DRKS00009846.