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AbstractEating at night has been linked to impaired glucose metabolism and dyslipidaemia that is likely a consequence of an underlying disrupted circadian rhythm in metabolic processes. An understanding of the mechanisms causing metabolic disruption after eating at night is important for prevention and management of disease risk factors. The aim of this study was to explore the transcriptomic differences in nutrient metabolism after eating a meal at night compared with the same meal in the morning. In a cross over design, 10 healthy adults fasted for > 10 hours and then completed two acute meal challenges at 8am and 8pm on non-consecutive days separated by a wash out. Fasting and postprandial blood samples were collected to assess glucose and insulin responses. For a subset of five participants RNA sequencing was completed on the Illumina NextSeq500. Total RNA was extracted from peripheral blood mononuclear cells at fasting (baseline) and 2 h after the test meal, the quality of all samples was above RIN 8 (AATI Fragment Analyzer). Differential expression analysis was completed using the DESeq2 package. False discovery rate correction was applied at the pathway analysis level, conducted in PathVisio. Postprandial blood glucose was significantly higher at 8pm vs. 8am (208.8(154.1)mmol/L.3hr vs 36.4(99.6)mmol/L.3hr, p = 0.005) no concurrent changes in insulin responses were observed (p = 0.100). Under fasting conditions, 704 genes were differentially expressed between morning and night, with 60% of these genes being down regulated at night. The meal challenges were associated with changes in gene expression compared with fasting in the morning 552 genes were differentially expressed and 532 genes were differentially expressed in the evening, however only 7% were commonly differentially regulated at both times of day. Pathway analysis of the differentially expressed genes identified that more immune system and signal transduction path

Gut appetite hormone responses may be influenced by meal macronutrients and obesity. The primary aim of this study was to examine in adolescents with obesity and of healthy weight the effect of a high-protein and a high-carbohydrate meal on postprandial gut appetite hormones. A postprandial cross-over study with adolescents 11–19 years old was undertaken. Participants consumed, in random order, a high 79% carbohydrate (HCHO) and a high 55% protein (HP) meal. Ghrelin, glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and self-reported appetite were assessed for four hours postprandial. Total energy intake from an ad libitum lunch and remaining 24 h was assessed. Eight adolescents with obesity (OB) and 12 with healthy weight (HW) participated. Compared with HW, OB adolescents displayed a smaller ghrelin iAUC (−25,896.5 ± 7943 pg/mL/4 h vs. −60,863.5 ± 13104 pg/mL/4 h) (p = 0.008) with no effect of meal (p > 0.05). The suppression of ghrelin relative to baseline was similar between OB and HW. Ghrelin suppression was greater following the HP vs. HCHO meal (effect of meal, p = 0.018). Glucose and insulin response were greater following HCHO vs. HP, with responses more marked in OB (time × weight × meal interaction, p = 0.003 and p = 0.018, respectively). There were no effects of weight or macronutrient on GLP-1 or PYY, appetite or subsequent energy intake. The present study demonstrates that dietary protein can modulate postprandial ghrelin responses; however, this did not translate to subsequent changes in subjective appetite or energy intake

The aim of this study was to explore the reliability and precision of body compartment measures, in particular visceral adipose tissue, in weight stable adults over a range of BMIs using GE-Lunar iDXA. Weight-stable participants aged 18⁻65 years had a total body composition scan on GE-Lunar iDXA either on three separate occasions over a three month period (n = 51), or on a single occasion for duplicate scans with repositioning (n = 30). The coefficient of variation (CV%) and least significant change (LSC) of body compartments were calculated. The CV was higher for all measures over three months (range 0.8⁻5.9%) compared with same-day precision-scans (all < 2%). The CV for visceral adipose tissue (VAT) was considerably higher than all other body compartments (42.2% three months, 16.2% same day scanning). To accurately measure VAT mass using the GE iDXA it is recommended that participants have a BMI ≥ 25 kg/m², or VAT mass > 500 g. Changes observed in VAT mass levels below 500 g should be interpreted with caution due to lack of precision and reliability. All other compartmental measures demonstrated good reliability, with less than 6% variation over three months.

Purpose: Although poor oral hygiene practices can have serious health consequences, a large number of adults brush or floss their teeth less than the recommended time or not at all. This study examined the mediating effect of two key self-regulatory processes, self-efficacy and planning, as the mechanisms that translate dental flossing intentions into behavior. Method: Participants (N = 629) comprised young adults attending a major university in Queensland, Australia. A longitudinal design guided by sound theory was adopted to investigate the sequential mediation chain for the effect of dental flossing intentions (time 1) on behavior (time 3) via self-efficacy and planning (time 2). Results: A latent variable structural equation model with standardized parameter estimates revealed the model was a good fit to the data. Controlling for baseline flossing, the effect of intentions on behavior was mediated via self-efficacy and planning, with 64 % of the flossing variance accounted for by this set of predictors. Controlling for age and sex did not change the results. Conclusion: The results extend previous research to further elucidate the mechanisms that help to translate oral hygiene intentions into behavior and make a significant contribution to the cumulative empirical evidence about self-regulatory components in health behavior change.

Introduction: Sleep restriction has been associated with poor dietary habits and is an increased risk factor for obesity. Whether obstructive sleep apnoea (OSA) confers a similar risk is uncertain. Comorbid depression and anxiety are common and are also well known to affect eating and physical activity patterns. This study aimed to compare the eating behaviours, appetite, mood, and levels of physical activity among those with and without OSA. Method(s): Data was prospectively collected from patients presenting over a 12 month period for a diagnostic sleep study. Anthropometric body measurements were collected using a body stat BIA, and patients were asked to complete medical, lifestyle, sleep, depression, anxiety and physical activity questionnaires prior to their sleep study. Eating habits were further analysed by way of the EPIC 24 hr food recall diary. Sleep has been analysed via a full in-lab polysomnogram. Patients without OSA were compared to patients with OSA. Result(s): 50 patients have been recruited to the study. 30 patients (60%) had OSA (taken as an apnoea-hypopnoea index of >5/hour) and 20 patients (40%) had a normal AHI (<=5/hour). 73% of subjects with OSA were male. Patients with OSA were older, with an average age of 48 years compared to 38 years. There was no difference in Epworth sleepiness score (8 and 7 respectively). There was no significant difference in average weight between the two groups, (82.5 kg versus 90.7 kg) or body mass index (28.97 vs 30.7). Patients without OSA tended to have higher depression and anxiety scores as measured by the PHQ-9 and GAD-7, respectively. Patients with OSA had a significantly higher total and saturated fat intake compared to patients without. The total and saturated fat questionnaire was used to assess this intake, with a score of >70 indicative of an urgent need to change the fat intake in the diet and a score between 50-70 suggesting that step I dietary recommendations are required. The average score of pati

Background: Excess body weight is a risk factor for obstructive sleep apnoea (OSA). The aim of the systematic review was to establish whether weight loss via lifestyle interventions such as diet and exercise are useful in the treatment of OSA. Method(s): A literature search was conducted between 1980 and February 2012. Systematic reviews and randomised controlled trials (RCTs) with participants who had OSA, were overweight or obese, and who had undergone lifestyle interventions with the aim of improving sleep apnoea were included. Meta analyses were conducted for a subset of RCTs with appropriate data. Result(s): Two systematic reviews and eight RCTs were included. Meta-analyses were conducted for four RCTs comparing intensive lifestyle interventions to a control. The overall weighted mean differences for weight change, change in apnoea -hypopnoea index (AHI) and change in oxygen desaturation index of >=4% were as follows: -13.76 kg (95% confidence interval (CI) -19.21, --8.32), -16.09 (95% CI -25.64, -6.54) and -14.18 (95% CI -24.23, -4.13), respectively. Although high heterogeneity within the meta analyses, all studies favoured the interventions. Long-term follow-up data from three RCTs suggest that improvements in weight and AHI are maintained for up to 60 months. Conclusion(s): Intensive lifestyle interventions are effective in the treatment of OSA, resulting in significant weight loss and a reduction in sleep apnoea severity. Weight loss via intensive lifestyle interventions could be encouraged as a treatment for mild to moderate OSA.Copyright © 2014.

Childhood obesity is a growing concern internationally. For prevention and treatment of obesity it would be beneficial to provide nutritional advice promoting the consumption of foods that provide a high level of satiety ('fullness') and which are low in energy ('calories'). The major nutrients in food: carbohydrate, protein and fat (i.e. macronutrients), influence the body's internal signals that control appetite. Seven obese and twelve healthy weight adolescents 12-19 years were randomised to complete 2 testing days involving the consumption of a high carbohydrate (79%) or high protein (55%) breakfast. Self reported hunger and fullness, and appetite hormones or energy expenditure were collected postprandially over 4 hours. This was followed by an ad libitum lunch and a 24 hour food recall. Preliminary results to date indicate differences in appetite between groups. Following the high protein breakfast, the obese group were significantly less hungry (p = 0.024) compared to the healthy weight group after 4 hours. Following the high carbohydrate breakfast, the obese group consumed significantly less at the buffet lunch per kg of body weight (p = 0.034) compared to the healthy weight group. The associations seen thus far indicate a relationship between macronutrient intake, body weight and subjective appetite sensations. Further recruitment to achieve the desired subject numbers, and ultimate analysis of the full set of outcomes including appetite hormones and energy expenditure will generate quality evidence towards the understanding and development of dietary advice for children.

The mammalian target of rapamycin (mTOR) pathway is the primary regulator of muscle protein synthesis. Metabolic syndrome (MetS) is characterized by central obesity and insulin resistance; little is known about how MetS affects the sensitivity of the mTOR pathway to feeding.