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Background: Recently, we demonstrated that whey protein (WP) combined with low dietary fiber improved lipemia, a risk factor for cardiovascular disease in subjects with abdominal obesity. In the present study, we investigated the effects of intake of WP and dietary fiber from enzyme-treated wheat bran on other metabolic parameters of the metabolic syndrome. Methods: The study was a 12-week, double-blind, randomized, controlled, parallel intervention study. We randomized 73 subjects with abdominal obesity to 1 of 4 iso-energetic dietary interventions: 60 g per day of either WP hydrolysate or maltodextrin (MD) combined with high-fiber (HiFi; 30 g dietary fiber/day) or low-fiber (LoFi; 10 g dietary fiber/day) cereal products. We assessed changes in insulin sensitivity, gut hormones (GLP-1, GLP-2, GIP, and peptide YY), body composition, 24-h BP, resting energy expenditure and respiratory exchange ratio (RER), and appetite. Results: Sixty-five subjects completed the trial. Subjective hunger ratings were lower after 12 weeks of WP compared with MD, independent of fiber content (P = 0.02). We found no effects on ratings of satiety, fullness or prospective food consumption for either of the interventions. Intake of WP combined with LoFi increased the postprandial peptide YY response. There were no effects of WP or fiber on insulin sensitivity, body composition, energy expenditure, incretins, or 24-h BP. Conclusions: WP consumption for 12 weeks reduced subjective ratings of hunger in subjects with abdominal obesity. Neither WP nor dietary fiber from wheat bran affected insulin sensitivity, 24-h BP, gut hormone responses, body composition, or energy expenditure compared with MD and low dietary fiber.

BACKGROUND/OBJECTIVES: To investigate whether intake of whey protein and butter naturally enriched in medium-chain fatty acids (MC-SFAs) (C6-C12) affected body composition, insulin sensitivity, blood pressure (BP) and plasma cholesterol concentrations.SUBJECTS/METHODS: A 12-week randomised, double-blinded, intervention study was completed in 52 abdominally obese adults. Subjects were assigned to one of four dietary supplementations: 63 g per day of milk fat with either high- (8.5 g per day) or low-MC-SFA (6.9 g per day) content combined with 60 g per day of whey or casein.We examined changes in the body composition by dual-energy X-ray absorption scan, insulin sensitivity using homoeostatic model assessment of insulin resistance (HOMA-IR) and Matsuda index, and diurnal BP and plasma cholesterol concentrations. Two-factor analysis of variance was used to examine the impact of MC-SFA content and protein type.RESULTS: We observed that lean body mass increased by 981 g (95% confidence interval (CI): 248-1713; P=0.010) after high-MC-SFA compared with low-MC-SFA supplementation. Concomitantly, total body-fat percentage increased by 0.70 percentage points (95% CI: 0.10-1.31; P=0.024) after intake of low-MC-SFA butter compared with intake of high-MC-SFA butter. Both changes were independent of protein type (P=0.96 and P=0.99, respectively). We found no difference in HOMA-IR, Matsuda index, diurnal BP or plasma cholesterol concentrations related to MC-SFA content or protein type.CONCLUSIONS: Enhanced intake of MC-SFA increased the lean body mass and caused a significantly lower total body-fat percentage compared with lower intake of MC-SFA. Consequently, the composition of dairy fat should be considered when evaluating the impact of dairy products on body composition.European Journal of Clinical Nutrition advance online publication, 9 November 2016; doi:10.1038/ejcn.2016.207.

Several studies emphasise that arabinoxylan and β-glucan have more beneficial effects on glucose metabolism than low-dietary fibre (DF) meals. Less attention has been paid to the effects of concentrated DF compared with whole grain. We compared the effects of DF and whole grain on glucose, hormone responses and appetite in subjects with the metabolic syndrome (MetS).Fifteen subjects with MetS participated in this acute, randomised, cross-over intervention study. The test breads provided 50 g of digestible carbohydrate: wheat bread with concentrated arabinoxylan (AX) or β-glucan (BG), rye bread with kernels (RK) and wheat bread (WB) as control. Blood samples were drawn for 270 min to determine glucose, insulin, glucagon-like peptide-1, glucose-dependent insulinotropic peptide (GIP) and ghrelin. Appetite score was addressed every 30 min. Ad libitum energy intake (EI) was measured 270 min after test meals.Compared with WB, BG and RK induced lower initial glycaemic responses (P0.001), whereas AX only reduced the glucose peak value (P0.001). RK reduced insulin (P0.001) and GIP responses (P0.001) compared with the other breads. BG lowered insulin responses more than AX (P0.001). AX, BG and RK increased satiety feeling (P0.001) more than WB, but did not differ significantly in terms of subsequent EI (P=0.089).BG and RK had beneficial impact on the glucose response, whereas AX had only effect on the postprandial glucose peak. The impact of the AX bread was influenced by higher protein content. Whether the metabolic effects of the breads are still present to mixed meals remains to be tested.

To study the postprandial blood glucose and insulin responses to exchangeable amounts of simple and complex carbohydrates, eight non-insulin-dependent diabetic subjects consumed 227 g apple, 280 g orange or 50 g white bread on three separate days. The mean postprandial blood glucose response area to white bread (404 +/- 95 mM x 240 min) was significantly higher compared with orange (131 +/- 34 mM x 240 min; P less than 0.05) and apple (157 +/- 57 mM x 240 min; P less than 0.05). Thr glycaemic indices of the fruits were identical: 44 +/- 13 (orange) and 40 +/- 11 (apple). The low glycaemic response to orange and apple may be ascribed to the high content of fructose which is rapidly cleared and metabolized by the liver, without elevating the blood glucose.