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Background: Although dietary flavonoid intake has been associated with less weight gain, there are limited data on its impact on fat mass, and to our knowledge, the contribution of genetic factors to this relation has not previously been assessed. Objective: We examined the associations between flavonoid intakes and fat mass. Design: In a study of 2734 healthy, female twins aged 18-83 y from the TwinsUK registry, intakes of total flavonoids and 7 subclasses (flavanones, anthocyanins, flavan-3-ols, flavonols, flavones, polymers, and proanthocyanidins) were calculated with the use of food-frequency questionnaires. Measures of dual-energy X-ray absorptiometry-derived fat mass included the limb-to-trunk fat mass ratio (FMR), fat mass index, and central fat mass index. Results: In cross-sectional multivariable analyses, higher intake of anthocyanins, flavonols, and proanthocyanidins were associated with a lower FMR with mean ± SE differences between extreme quintiles of 20.036 0.02 (P-trend = 0.02),20.03 ± 0.02 (P-trend = 0.03), and 20.05 ± 0.02 (P-trend < 0.01), respectively. These associations were not markedly changed after further adjustment for fiber and total fruit and vegetable intakes. In monozygotic, intakediscordant twin pairs, twins with higher intakes of flavan-3-ols (n = 154, P = 0.03), flavonols (n = 173, P = 0.03), and proanthocyanidins (n = 172, P < 0.01) had a significantly lower FMR than that of their co-twins with within-pair differences of 3-4%. Furthermore, in confirmatory food-based analyses, twins with higher intakes of flavonolrich foods (onions, tea, and pears; P = 0.01) and proanthocyanidin-rich foods (apples and cocoa drinks; P = 0.04) and, in younger participants (aged <50 y) only, of anthocyanin-rich foods (berries, pears, grapes, and wine; P = 0.01) had a 3-9% lower FMR than that of their co-twins. Conclusions: These data suggest that higher habitual intake of a number of flavonoids, including anthocyanins, flavan-3-ols, flavonols, and proanthocyanidins, are associated with lower fat mass independent of shared genetic and common environmental factors. Intervention trials are needed to further examine the effect of flavonoid-rich foods on body composition. [ABSTRACT FROM AUTHOR]

Background: Passive overconsumption is the increase in energy intake driven by the high-fat energy-dense food environment. This can be explained in part because dietary fat has a weaker effect on satiation (i.e. process that terminates feeding). Habitually active individuals show improved satiety (i.e. process involved in post-meal suppression of hunger) but any improvement in satiation is unknown. Here we examined whether habitual physical activity mitigates passive overconsumption through enhanced satiation in response to a high-fat meal. Methods: Twenty-one non-obese individuals with high levels of physical activity (HiPA) and 19 individuals with low levels of physical activity (LoPA) matched for body mass index (mean = 22.8 kg/m²) were recruited. Passive overconsumption was assessed by comparing ad libitum energy intake from covertly manipulated high-fat (HFAT; 50% fat) or high-carbohydrate (HCHO; 70% carbohydrate) meals in a randomized crossover design. Habitual physical activity was assessed using SenseWear accelerometers (SWA). Body composition, resting metabolic rate, eating behaviour traits, fasting appetite-related peptides and hedonic food reward were also measured. Results: In the whole sample, passive overconsumption was observed with greater energy intake at HFAT compared to HCHO (p < 0.01), without any differences between activity groups (p > 0.05). SWA confirmed that HiPA were more active than LoPA (p < 0.01). HiPA had lower body fat and greater fat-free mass than LoPA (p < 0.05 for both) but did not differ in resting metabolic rate, eating behaviour traits, appetite-related peptides or food reward (p > 0.05 for all). Conclusions: Non-obese individuals with high or low physical activity levels but matched for BMI showed similar susceptibility to passive overconsumption when consuming an ad libitum high-fat compared to a high-carbohydrate meal. This occurred despite increased total daily energy expenditure and improved body composition in HiPA. Greater differences in body composition and/or physical activity levels may be required to impact on satiation. [ABSTRACT FROM AUTHOR]

Background: The beneficial cardiovascular effects of vegetables may be underpinned by their high inorganic nitrate content. Objective: We sought to examine the effects of a 6-wk once-daily intake of dietary nitrate (nitrate-rich beetroot juice) compared with placebo intake (nitrate-depleted beetroot juice) on vascular and platelet function in untreated hypercholesterolemics. Design: A total of 69 subjects were recruited in this randomized, double-blind, placebo-controlled parallel study. The primary endpoint was the change in vascular function determined with the use of ultrasound flow-mediated dilatation (FMD). Results: Baseline characteristics were similar between the groups, with primary outcome data available for 67 patients. Dietary nitrate resulted in an absolute increase in the FMD response of 1.1% (an ~24% improvement from baseline) with a worsening of 0.3% in the placebo group (P < 0.001). A small improvement in the aortic pulse wave velocity (i.e., a decrease of 0.22 m/s; 95% CI: -0.4, -0.3 m/s) was evident in the nitrate group, showing a trend (P = 0.06) to improvement in comparison with the placebo group. Dietary nitrate also caused a small but significant reduction (7.6%) in platelet-monocyte aggregates compared with an increase of 10.1% in the placebo group (P = 0.004), with statistically significant reductions in stimulated (ex vivo) P-selectin expression compared with the placebo group (P < 0.05) but no significant changes in unstimulated expression. No adverse effects of dietary nitrate were detected. The composition of the salivary microbiome was altered after the nitrate treatment but not after the placebo treatment (P < 0.01). The proportions of 78 bacterial taxa were different after the nitrate treatment; of those taxa present, 2 taxa were responsible for >1% of this change, with the proportions of Rothia mucilaginosa trending to increase and Neisseria flavescens (P < 0.01) increased after nitrate treatment relative to after placebo treatment. Conclusions: Sustained dietary nitrate ingestion improves vascular function in hypercholesterolemic patients. These changes are associated with alterations in the oral microbiome and, in particular, nitrate-reducing genera. Our findings provide additional support for the assessment of the potential of dietary nitrate as a preventative strategy against atherogenesis in larger cohorts. This trial was registered at clinicaltrials.gov as NCT01493752. [ABSTRACT FROM AUTHOR]

Background: The manipulation of the composition of foods consumed as between-meal snacks may aid daily energy restriction. Objectives: We compared the effects of the consumption of 2 energy-matched snack bars on appetite, energy intake (EI), and metabolic and endocrine responses. In addition, we investigated whether the acute effects of the consumption of snacks were maintained under free-living conditions and whether the habitual daily consumption of the snack over 14 d influenced these effects. Design: Ten lean men [mean ± SD age: 30.7 ± 9.7 y; body mass index (in kg/m²): 23.2 ± 2.8] consumed a whey protein and polydextrose (PPX) snack bar or an isoenergetic control snack bar as a midmorning, between-meal snack for 14 consecutive days in a double-blind, randomized, crossover design. The two 14-d intervention phases were separated by a 14-d washout period. On the first (day 1) and last (day 15) days of each intervention phase, appetite, food intake, and blood metabolite and endocrine responses were assessed under laboratory conditions. Free-living EI was recorded on days 4, 8, and 12 of interventions. Results: Total daily EI was significantly lower when the PPX snack was consumed during experimental days (10,149 ± 831 compared with 11,931 ± 896 kJ; P < 0.01), and daily EI remained lower when the PPX snack was consumed during the free-living part of the intervention (7904 ± 610 compared with 9041 ± 928 kJ; P < 0.05). The PPX snack was associated with lower glucose and ghrelin and higher glucagon-like peptide 1 and peptide tyrosine-tyrosine responses. Conclusion: The manipulation of the composition of foods consumed as snacks is an effective way to limit subsequent EI. This trial was registered at clinicaltrials.gov as NCT01927926. [ABSTRACT FROM AUTHOR]

Context: Cooling the neck region can improve the ability to exercise in a hot environment. It might improve performance by dampening the perceived level of thermal strain, allowing individuals to override inhibitory signals. Objective: To investigate whether the enhanced ability to exercise in a hot environment observed when cooling the neck region occurs because of dampening the perceived level of thermal strain experienced and the subsequent overriding of inhibitory signals. Design: Crossover study. Setting: Walk-in environmental chamber. Patients or Other Participants: Eight endurance-trained, nonacclimated men (age = 26 ± 2 years, height = 1.79 ± 0.04 m, mass = 77.0 ± 6.2 kg, maximal oxygen uptake [VO2max] = 56.2 ± 9.2 mL·kg-1·min-1) participated. Intervention(s): Participants completed 4 running tests at approximately 70% VO2max to volitional exhaustion: 2 familiarization trials followed by 2 experimental trials (cooling collar [CC] and no collar [NC]). Trials were separated by 7 days. Familiarization and NC trials were performed without a collar and used to assess the test variability. Main Outcome Measure(s): Time to volitional exhaustion, heart rate, rectal temperature, neck skin temperature, rating of perceived exertion, thermal sensation, and feeling scale (pleasure/displeasure) were measured. Results: Time to volitional exhaustion was increased by 13.5% ± 3.8% (CC = 43.15 ± 12.82 minutes, NC = 38.20 ± 11.70 minutes; t7 = 9.923, P < .001) with the CC, which reduced mean neck skin temperature throughout the test (P < .001). Participants terminated exercise at identical levels of perceived exertion, thermal sensation, and feeling scale, but the CC enabled participants to tolerate higher rectal temperatures (CC = 39.61 °C ± 0.45°C, NC = 39.18°C ± 0.7°C; t7 = -3.217, P = .02) and heart rates (CC = 181 ± 6 beats/min, NC = 178 ± 9 beats/min; t7 = -2.664, P = .03) at the point of termination. Conclusions: Cooling the neck increased the time taken to reach volitional exhaustion by dampening the perceived levels of thermal strain. [ABSTRACT FROM AUTHOR]