Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium that causes pneumonia in immunocompromised humans and severe pulmonary damage in patients with cystic fibrosis. Imbalanced fatty acid incorporation in membranes, including increased arachidonic acid and decreased DHA concentrations, is known to play a critical role in chronic inflammation associated with bacterial infection. Other lipids, such as EPA and alkylglycerols, are also known to play a role in inflammation, particularly by stimulating the immune system, decreasing inflammation and inhibiting bacterial growth. In this context, the goal of the present study was to assess the effect of dietary DHA/EPA, in a 2:1 ratio, and alkylglycerols, as natural compounds extracted from oils of rays and chimeras, respectively, on the inflammatory reaction induced by P. aeruginosa pulmonary infection in mice. To this end, mice were fed with a control diet or isolipidic, isoenergetic diets prepared with oils enriched in DHA/EPA (2:1) or alkylglycerols for 5 weeks before the induction of acute P. aeruginosa lung infection by endotracheal instillation. In our model, DHA/EPA (2:1) significantly improved the survival of mice after infection, which was associated with the acceleration of bacterial clearance and the resolution of inflammation leading to the improvement of pulmonary injuries. By contrast, alkylglycerols did not affect the outcomes of P. aeruginosa infection. Our findings suggest that supplementation with ray oil enriched in DHA/EPA (2:1) can be considered as a preventive treatment for patients at risk for P. aeruginosa infection.

Pathogenic invasion by Escherichia coli and Salmonellae remains a constant threat to the integrity of the intestinal epithelium and can rapidly induce inflammatory responses. At birth, colostrum consumption exerts numerous beneficial effects on the properties of intestinal epithelial cells and protects the gastrointestinal tract of newborns from pathogenic invasion. The present study aimed to investigate the effect of colostrum on the early and late inflammatory responses induced by pathogens. The short-term (2 h) and long-term (24 h) effects of exposure to heat-killed (HK) E. coli and Salmonella enterica Typhimurium on gene expression in the porcine intestinal epithelial cell (IPEC-J2) model were first evaluated by microarray and quantitative PCR analyses. Luciferase assays were performed using a NF-κB-luc reporter construct to investigate the effect of colostrum whey treatment on the activation of NF-κB induced by HK bacteria. Luciferase assays were also performed using NF-κB-luc, IL-8-luc and IL-6-luc reporter constructs in human colon adenocarcinoma Caco-2/15 cells exposed to dose–response stimulations with HK bacteria and colostrum whey. Bovine colostrum whey treatment decreased the expression of early and late inflammatory genes induced by HK bacteria in IPEC-J2, as well as the transcriptional activation of NF-κB-luc induced by HK bacteria. Unlike that with colostrum whey, treatment with other milk fractions failed to decrease the activation of NF-κB-luc induced by HK bacteria. Lastly, the reduction of the HK bacteria-induced activation of NF-κB-luc, IL-8-luc and IL-6-luc by colostrum whey was dose dependent. The results of the present study indicate that bovine colostrum may protect and preserve the integrity of the intestinal mucosal barrier in the host by controlling the expression levels of early and late inflammatory genes following invasion by enteric pathogens.

Both Fe deficiency and poor n-3 fatty acid status have been associated with behavioural changes in children. In the present study, we investigated the effects of Fe and DHA+EPA supplementation, alone or in combination, on physical activity during school days and on teacher-rated behaviour in healthy Fe-deficient school children. In a 2 × 2 factorial design, children (n 98, 6–11 years) were randomly assigned to receive (1) Fe (50 mg) plus DHA (420 mg)+EPA (80 mg), (2) Fe plus placebo, (3) placebo plus DHA+EPA or (4) placebo plus placebo as oral supplements (4 d/week) for 8·5 months. Physical activity was measured during four school days at baseline and endpoint using accelerometers, and data were stratified into morning class time (08.00–10.29 hours), break time (10.30–11.00 hours) and after-break class time (11.01–12.00 hours) for analysis. Classroom behaviour was assessed at endpoint using Conners’ Teacher Rating Scales. DHA+EPA supplementation decreased physical activity counts during morning class time, increased sedentary physical activity, and decreased light- and moderate-intensity physical activities. Consistently, DHA+EPA supplementation increased sedentary physical activity and decreased light-intensity physical activity during after-break class time. Even though there were no treatment effects found on teacher-rated behaviour, lower physical activity during morning class time was associated with lower levels of teacher-rated hyperactivity and oppositional behaviour at endpoint. Despite a positive association between Fe status and physical activity during break time at baseline, Fe supplementation did not affect physical activity during break time and class time. Our findings suggest that DHA+EPA supplementation may decrease physical activity levels during class time, and further indicate that accelerometry might be a useful tool to assess classroom behaviour in healthy children.

Wheat bran extract (WBE), containing arabinoxylan-oligosaccharides that are potential prebiotic substrates, has been shown to modify bacterial colonic fermentation in human subjects and to beneficially affect the development of colorectal cancer (CRC) in rats. However, it is unclear whether these changes in fermentation are able to reduce the risk of developing CRC in humans. The aim of the present study was to evaluate the effects of WBE on the markers of CRC risk in healthy volunteers, and to correlate these effects with colonic fermentation. A total of twenty healthy subjects were enrolled in a double-blind, cross-over, randomised, controlled trial in which the subjects ingested WBE (10 g/d) or placebo (maltodextrin, 10 g/d) for 3 weeks, separated by a 3-week washout period. At the end of each study period, colonic handling of NH3 was evaluated using the biomarker lactose[15N, 15N′]ureide, colonic fermentation was characterised through a metabolomics approach, and the predominant microbial composition was analysed using denaturing gradient gel electrophoresis. As markers of CRC risk, faecal water genotoxicity was determined using the comet assay and faecal water cytotoxicity using a colorimetric cell viability assay. Intake of WBE induced a shift from urinary to faecal 15N excretion, indicating a stimulation of colonic bacterial activity and/or growth. Microbial analysis revealed a selective stimulation of Bifidobacterium adolescentis. In addition, WBE altered the colonic fermentation pattern and significantly reduced colonic protein fermentation compared with the run-in period. However, faecal water cytotoxicity and genotoxicity were not affected. Although intake of WBE clearly affected colonic fermentation and changed the composition of the microbiota, these changes were not associated with the changes in the markers of CRC risk.

Consumption of carbohydrate-containing foods leads to transient postprandial rises in blood glucose concentrations that vary between food types. Higher postprandial glycaemic exposures have particularly been implicated in the development of chronic cardiometabolic diseases. Reducing such diet-related exposures may be beneficial not only for diabetic patients but also for the general population. A variety of markers have been used to track different aspects of glycaemic exposures, with most of the relevant knowledge derived from diabetic patients. The assessment of glycaemic exposures among the non-diabetic population may require other, more sensitive markers. The present report summarises key messages of presentations and related discussions from a workshop organised by Unilever intended to consider currently applied markers of glycaemic exposure. The particular focus of the meeting was to identify the potential applicability of glycaemic exposure markers for studying dietary effects in the non-diabetic population. Workshop participants concluded that markers of glycaemic exposures are sparsely used in intervention studies among non-diabetic populations. Continuous glucose monitoring remains the optimal approach to directly assess glycaemic exposure. Markers of glycaemic exposure such as glycated Hb, fructosamine, glycated albumin, 1,5-anhydroglucitol and advanced glycation end products can be preferred dependent on the aspect of interest (period of exposure and glucose variability). For all the markers of glycaemia, the responsiveness to interventions will probably be smaller among the non-diabetic than among the diabetic population. Further validation and acceptance of existing glycaemic exposure markers applied among the non-diabetic population would aid food innovation and better design of dietary interventions targeting glycaemic exposure.

Dietary intake/status of the trace mineral Se may affect the risk of developing hypertensive conditions of pregnancy, i.e. pre-eclampsia and pregnancy-induced hypertension (PE/PIH). In the present study, we evaluated Se status in UK pregnant women to establish whether pre-pregnant Se status or Se supplementation affected the risk of developing PE/PIH. The samples originated from the SPRINT (Selenium in PRegnancy INTervention) study that randomised 230 UK primiparous women to treatment with Se (60 μg/d) or placebo from 12 weeks of gestation. Whole-blood Se concentration was measured at 12 and 35 weeks, toenail Se concentration at 16 weeks, plasma selenoprotein P (SEPP1) concentration at 35 weeks and plasma glutathione peroxidase (GPx3) activity at 12, 20 and 35 weeks. Demographic data were collected at baseline. Participants completed a FFQ. UK pregnant women had whole-blood Se concentration lower than the mid-range of other populations, toenail Se concentration considerably lower than US women, GPx3 activity considerably lower than US and Australian pregnant women, and low baseline SEPP1 concentration (median 3·00, range 0·90–5·80 mg/l). Maternal age, education and social class were positively associated with Se status. After adjustment, whole-blood Se concentration was higher in women consuming Brazil nuts (P= 0·040) and in those consuming more than two seafood portions per week (P= 0·054). A stepwise logistic regression model revealed that among the Se-related risk factors, only toenail Se (OR 0·38, 95 % CI 0·17, 0·87, P= 0·021) significantly affected the OR for PE/PIH. On excluding non-compliers with Se treatment, Se supplementation also significantly reduced the OR for PE/PIH (OR 0·30, 95 % CI 0·09, 1·00, P= 0·049). In conclusion, UK women have low Se status that increases their risk of developing PE/PIH. Therefore, UK women of childbearing age need to improve their Se status.

The scientific community has become increasingly interested in the overall quality of diets rather than in single food-based or single nutrient-based approaches to examine diet–disease relationships. Despite the plethora of indices used to measure diet quality, there still exist questions as to which of these can best predict health outcomes. The present study aimed to compare the ability of five diet quality indices, namely the Recommendation Compliance Index (RCI), Diet Quality Index-International (DQI-I), Dietary Approaches to Stop Hypertension (DASH), Mediterranean Diet Score (MDS), and Dietary Inflammatory Index (DII), to detect changes in chronic disease risk biomarkers. Nutritional data from 1352 participants, aged 18–69 years, of the Luxembourg nationwide cross-sectional ORISCAV-LUX (Observation of Cardiovascular Risk Factors in Luxembourg) study, 2007–8, were used to calculate adherence to the diet quality index. General linear modelling was performed to assess trends in biomarkers according to adherence to different dietary patterns, after adjustment for age, sex, education level, smoking status, physical activity and energy intake. Among the five selected diet quality indices, the MDS exhibited the best ability to detect changes in numerous risk markers and was significantly associated with lower levels of LDL-cholesterol, apo B, diastolic blood pressure, renal function indicators (creatinine and uric acid) and liver enzymes (serum γ-glutamyl-transpeptidase and glutamate-pyruvate transaminase). Compared with other dietary patterns, higher adherence to the Mediterranean diet is associated with a favourable cardiometabolic, hepatic and renal risk profile. Diets congruent with current universally accepted guidelines may be insufficient to prevent chronic diseases. Clinicians and public health decision makers should be aware of needs to improve the current dietary guidelines.

The consumption of ready-made meals, such as pre-packaged dishes, available at grocery stores and fast-food restaurants, is a habit related to our modern fast-paced lives. No study has examined the association of daily ready-made meal consumption with diet quality or health-related outcomes. The present study aimed to investigate the association between self-reported ready-made meal consumption and diet quality, as measured by compliance with dietary recommendations and with a set of adiposity measures, in a nationally representative sample of 1352 subjects, aged 18–69 years, participating in the nationwide population-based ORISCAV-LUX (Observation of Cardiovascular Risk Factors in Luxembourg) survey. The daily consumption of ready-made meals was calculated as follows: frequency of consumption × portion size × number of portions consumed. The sum of the daily consumption values of the eleven pre-packaged dishes included in the FFQ represented the total daily consumption of ready-made meals (g/d) for each participant. About 97 % of the participants reported daily consumption of ready-made meals. The intake was highly prevalent in men living alone and varied according to education level. Ready-made meal consumption provided >7 % of total daily energy. The fractions (%) of macro- and micronutrients derived from daily consumption of ready-made meals varied from 10 % for total cholesterol to 0·65 % for total fibre. Increased consumption of ready-made meals was found to be independently associated with abdominal obesity. On controlling for age, sex, socio-economic status and lifestyle factors, daily consumption of ready-made meals was found to be associated with higher energy intake and with poor compliance with national nutritional recommendations, and hence it could plausibly increase the risk of central obesity and fat deposition.

Previous studies have shown that various dietary components may be implicated in the aetiology of prostate cancer, although the results remain equivocal. The possible relationship of inflammation derived from dietary exposures with prostate cancer risk has not been investigated. We examined the ability of a newly developed dietary inflammatory index (DII) to predict prostate cancer risk in a case–control study conducted in Italy between 1991 and 2002. A total of 1294 patients aged < 75 years with incident, histologically confirmed carcinoma of the prostate served as cases. A total of 1451 subjects aged < 75 years who were admitted to the same hospitals as cases for a wide spectrum of acute, non-neoplastic conditions served as controls. The DII was computed based on dietary intake assessed using a previously validated seventy-eight-item FFQ. Logistic regression models were used to estimate multivariable OR adjusted for age, study centre, years of education, social class, BMI, smoking status, family history of prostate cancer and total energy intake. Men with higher DII scores had a higher risk of prostate cancer when analysed using the DII as both continuous (OR 1·06, 95 % CI 1·00, 1·13) and categorical, i.e. compared with men in the lowest quartile of the DII, men in the third and fourth quartiles were at elevated risk (ORQuartile 3 v. 1 1·32, 95 % CI 1·03, 1·69 and ORQuartile 4 v. 1 1·33, 95 % CI 1·01, 1·76; Ptrend= 0·04). These data suggest that a pro-inflammatory diet, as indicated by the increasing DII score, is a risk factor of prostate cancer in Italian men.

Preliminary research has suggested that wearable cameras may reduce under-reporting of energy intake (EI) in self-reported dietary assessment. The aim of the present study was to test the validity of a wearable camera-assisted 24 h dietary recall against the doubly labelled water (DLW) technique. Total energy expenditure (TEE) was assessed over 15 d using the DLW protocol among forty adults (n 20 males, age 35 (sd 17) years, BMI 27 (sd 4) kg/m2 and n 20 females, age 28 (sd 7) years, BMI 22 (sd 2) kg/m2). EI was assessed using three multiple-pass 24 h dietary recalls (MP24) on days 2–4, 8–10 and 13–15. On the days before each nutrition assessment, participants wore an automated wearable camera (SenseCam (SC)) in free-living conditions. The wearable camera images were viewed by the participants following the completion of the dietary recall, and their changes in self-reported intakes were recorded (MP24+SC). TEE and EI assessed by the MP24 and MP24+SC methods were compared. Among men, the MP24 and MP24+SC measures underestimated TEE by 17 and 9 %, respectively (P< 0·001 and P= 0·02). Among women, these measures underestimated TEE by 13 and 7 %, respectively (P< 0·001 and P= 0·004). The assistance of the wearable camera (MP24+SC) reduced the magnitude of under-reporting by 8 % for men and 6 % for women compared with the MP24 alone (P< 0·001 and P< 0·001). The increase in EI was predominantly from the addition of 265 unreported foods (often snacks) as revealed by the participants during the image review. Wearable cameras enhance the accuracy of self-report by providing passive and objective information regarding dietary intake. High-definition image sensors and increased imaging frequency may improve the accuracy further.

Previous studies have shown that various dietary components may be implicated in the aetiology of pancreatic cancer. However, the possible relationship between diet-related inflammation and the risk of pancreatic cancer has not yet been investigated. We examined the ability of a newly developed literature-derived dietary inflammatory index (DII) to predict the risk of pancreatic cancer in a case–control study conducted in Italy between 1991 and 2008. This included 326 incident cases and 652 controls admitted to the major teaching and general hospitals for non-neoplastic diseases, frequency-matched to cases by study centre, sex and age. The DII was computed based on dietary intake assessed using a validated and reproducible seventy-eight-item FFQ. Logistic regression models were used to estimate multivariable OR adjusted for age, sex, study centre, education, BMI, smoking status, alcohol drinking and history of diabetes. Energy adjustment was performed using the residual method. Subjects with higher DII scores (i.e. representing a more pro-inflammatory diet) had a higher risk of pancreatic cancer, with the DII being used as both a continuous variable (ORcontinuous 1·24, 95 % CI 1·11, 1·38) and a categorical variable (i.e. compared with the subjects in the lowest quintile of the DII, those in the second, third, fourth and fifth quintiles had, respectively, ORquintile2 v. 1 1·70, 95 % CI 1·02, 2·80; ORquintile3 v. 1 1·91, 95 % CI 1·16, 3·16; ORquintile4 v. 1 1·98, 95 % CI 1·20, 3·27; ORquintile5 v. 1 2·48, 95 % CI 1·50, 4·10; Ptrend= 0·0015). These data suggest that a pro-inflammatory diet increases the risk of pancreatic cancer.

Soya foods are one of the recommended alternatives to meat in many dietary guidelines. While this is expected to increase the intake of some nutrients, potential concerns regarding others have been raised. The purpose of the present study was to examine the prevalence and the association of soya food consumption with nutrient intakes and dietary patterns of Canadians (age ≥ 2 years). Cross-sectional data from the 2004 Canadian Community Health Survey (Cycle 2.2; n 33 218) were used to classify soya consumers and non-consumers. Soya consumers were further divided into two groups based on their soya protein intake. Sample weights were applied and logistic regression analysis was used to explore the association between nutrient intakes and soya consumption, with cultural background, sex, age and economic status being included as covariates. On any given day, 3·3 % (n 1085) of Canadians consume soya foods, with females, Asian Canadians and adults with post-secondary education being more likely to be soya consumers. As a whole, adolescent and adult respondents who had consumed at least one soya food during their 24 h dietary recall had higher energy intakes, as well as increased intakes of nutrients such as protein, fibre, vitamin C, vitamin B6, naturally occurring folate, thiamin, Ca, P, Mg, PUFA, Fe and K and lowered intakes of saturated fat. These data indicate that soya food consumption is associated with improved diet quality of Canadians. However, future research is necessary to investigate the association between increased energy intake and soya consumption.

Because of the discretionary nature of voluntary food fortification in the European Union, there is a need to monitor fortification practices and consumption of fortified foods in order to assess the efficacy and safety of such additions on an ongoing basis. The present study aimed to investigate the nutritional impact of changes in voluntary fortification practices in adults aged 18–64 years using dietary intake data from two nationally representative cross-sectional food consumption surveys, the North/South Ireland Food Consumption Survey (NSIFCS) (1997–9) and the National Adult Nutrition Survey (NANS) (2008–10). The supply of fortified foods increased between 1997–9 and 2008–10, resulting in a higher proportion of adults consuming fortified foods (from 67 to 82 %) and a greater contribution to mean daily energy intake (from 4·6 to 8·4 %). The overall nutrient profile of fortified foods consumed remained favourable, i.e. higher in starch and dietary fibre and lower in fat and saturated fat, with polyunsaturated fat, sugars and Na in proportion to energy. Women, particularly those of childbearing age, remained the key beneficiaries of voluntary fortification practices in Ireland. Continued voluntary fortification of foods has increased protection against neural tube defect-affected pregnancy by folic acid and maintained the beneficial impact on the adequacy of Fe intake. Increased consumption of fortified foods did not contribute to an increased risk of intakes exceeding the tolerable upper intake level for any micronutrient. Recent increases in voluntary fortification of foods in Ireland have made a favourable nutritional impact on the diets of adults and have not contributed to an increased risk of adverse effects.

Improvement of insulin resistance and inflammation is a basic strategy in the management of type 2 diabetes. There is limited evidence that prebiotics improve insulin resistance and inflammation. However, the ameliorating effect of resistant dextrin, as a prebiotic, on insulin resistance and inflammation in patients with type 2 diabetes has not been investigated so far. Therefore, the present study aimed to examine the effects of resistant dextrin on insulin resistance and inflammation in type 2 diabetic patients. In a randomised controlled clinical trial, fifty-five women with type 2 diabetes were assigned to two groups: the intervention group (n 30) and the control group (n 25). The intervention group received a daily supplement of 10 g resistant dextrin and the control group received a similar amount of maltodextrin as placebo for 8 weeks. Fasting plasma glucose (FPG), HbA1c, insulin, high-sensitivity C-reactive protein (hs-CRP), IL-6, TNF-α, malondialdehyde (MDA) and serum endotoxin concentrations were measured before and after the intervention. Data were analysed using SPSS (version 13). Paired and unpaired t tests and ANCOVA were used to compare quantitative variables after the intervention. Patients supplemented with resistant dextrin exhibited a significant decrease in fasting insulin (20·1 pmol/l, 22·8 %), homeostasis model assessment of insulin resistance (1·3, 24·9 %), quantitative insulin sensitivity check index (0·2, 7·2 %), IL-6 (1·4 pg/ml, 28·4 %), TNF-α (5·4 pg/ml, 18·8 %), MDA (1·2 nmol/ml, 25·6 %) and endotoxin (6·2 endotoxin units/ml, 17·8 %) concentrations than those supplemented with maltodextrin (P< 0·05). Decreases in FPG (0·05 mmol/l, 0·6 %), HbA1c (0·5 %, 9·6 %) and hs-CRP (2·7 ng/ml, 35·1 %) concentrations in the resistant dextrin group were not significant when compared with the maltodextrin group. In conclusion, resistant dextrin supplementation can modulate inflammation and improve insulin resistance in women with type 2 diabetes.

The present study analyses the gene expression profile of peripheral blood mononuclear cells (PBMC) from obese boys. The aims of the present study were to identify baseline differences between low responders (LR) and high responders (HR) after 10 weeks of a moderate energy-restricted dietary intervention, and to compare the gene expression profile between the baseline and the endpoint of the nutritional intervention. Spanish obese boys (age 10–14 years) were advised to follow a 10-week moderate energy-restricted diet. Participants were classified into two groups based on the association between the response to the nutritional intervention and the changes in BMI standard deviation score (BMI-SDS): HR group (n 6), who had a more decreased BMI-SDS; LR group (n 6), who either maintained or had an even increased BMI-SDS. The expression of 28 869 genes was analysed in PBMC from both groups at baseline and after the nutritional intervention, using the Affymetrix Human Gene 1.1 ST 24-Array plate microarray. At baseline, the HR group showed a lower expression of inflammation and immune response-related pathways, which suggests that the LR group could have a more developed pro-inflammatory phenotype. Concomitantly, LEPR and SIRPB1 genes were highly expressed in the LR group, indicating a tendency towards an impaired immune response and leptin resistance. Moreover, the moderate energy-restricted diet was able to down-regulate the inflammatory ‘mitogen-activated protein kinase signalling pathway’ in the HR group, as well as some inflammatory genes (AREG and TNFAIP3). The present study confirms that changes in the gene expression profile of PBMC in obese boys may help to understand the weight-loss response. However, further research is required to confirm these findings.

The dietary patterns of immigrants usually change with the duration of residence and progressively resemble those of the host country. However, very few studies have investigated individuals migrating to countries with a high-quality diet, such as the Mediterranean diet (MD), and none has yet focused on Latin-American immigrants. The present study examined the association of the duration of residence with obesity-related eating habits and dietary patterns among Latin-American immigrants residing in Spain. A cross-sectional study was conducted in 2008–10 in a representative sample of the adult population residing in Spain. Adherence to the MD was defined as a MD Adherence Screener score ≥ 9. Analyses were conducted by including 419 individuals aged 18–64 years born in Latin-American countries. Compared with immigrants residing in Spain for < 5 years, those residing for ≥ 10 years accounted for a lower percentage of individuals who habitually ate at fast-food restaurants and never trimmed visible fat from meat. Moreover, these immigrants were found to have a lower intake of sugary beverages and a higher intake of Na, saturated fat, fibre, olive oil, vegetables and fish and to more frequently strictly adhere to the MD. A longer duration of residence in Spain was found to be associated with both healthy and unhealthy changes in some eating habits and dietary patterns among Latin-American immigrants. Some of the healthy changes observed contrasted the ‘Westernisation’ of the diet reported in studies conducted in other Western countries. The results of the present study support the role of the food environment of the host country in the modification of the dietary patterns of immigrants.

Common pharmacological treatments of mood disorders aim to modulate serotonergic neurotransmission and enhance serotonin levels in the brain. Brain serotonin levels are dependent on the availability of its food-derived precursor essential amino acid tryptophan (Trp). We tested the hypothesis that delivery of Trp via food may serve as an alternative treatment, and examined the effects of a Trp-rich, bioavailable dietary supplement from egg protein hydrolysate on cognitive and emotional functions, mood state, and sleep quality. In a randomised, placebo-controlled, parallel trial, fifty-nine mentally and physically healthy women aged 45–65 years received placebo (n 30) or the supplement (n 29) (both as 0·5 g twice per d) for 19 d. Emotional processing was significantly changed by supplementation, exhibiting a shift in bias away from negative stimuli. The results for the Affective Go/No-Go Task exhibited a slowing of responses to negative words, suggesting reduced attention to negative emotional stimuli. The results for the Facial Emotional Expression Rating Task also supported a shift away from attention to negative emotions and a bias towards happiness. An increase in arousal-like symptoms, labelled ‘high energy’, shorter reaction times and a slight benefit to sustained attention were observed in the treated subjects. Finally, when the supplement was taken 60–90 min before bedtime, a feeling of happiness before going to bed was consistently reported. In summary, daily consumption of a low-dose supplement containing bioavailable Trp may have beneficial effects on emotional and cognitive functions.

Excessive sugar-sweetened beverage (SSB) consumption has been associated with overweight and obesity. Caffeine is a common additive to SSB, and through dependence effects, it has the potential to promote the consumption of caffeine-containing foods. The objective of the present study was to assess the influence that caffeine has on the consumption of SSB. Participants (n 99) were blindly assigned to either a caffeinated SSB (C-SSB) or a non-caffeinated SSB (NC-SSB) group. Following randomisation, all participants completed a 9 d flavour-conditioning paradigm. They then completed a 28 d ad libitum intake intervention where they consumed as much or as little of C-SSB or NC-SSB as desired. The amount consumed (ml) was recorded daily, 4 d diet diaries were collected and liking of SSB was assessed at the start and end of the intervention. Participants (n 50) consuming the C-SSB had a daily SSB intake of 419 (sd 298) ml (785 (sd 559) kJ/d) over the 28 d intervention, significantly more than participants (n 49) consuming the NC-SSB (273 (sd 278) ml/d, 512 (sd 521) kJ/d) (P< 0·001). A trained flavour panel (n 30) found no difference in flavour between the C-SSB and NC-SSB (P>0·05). However, participants who consumed the C-SSB liked the SSB more than those who consumed the NC-SSB (6·3 v. 6·0 on a nine-point hedonic scale, P= 0·022). The addition of low concentrations of caffeine to the SSB significantly increases the consumption of the SSB. Regulating caffeine as a food additive may be an effective strategy to decrease the consumption of nutrient-poor high-energy foods and beverages.

The present study examined the underlying mechanisms by which whey protein isolate (WPI) affects energy balance. C57BL/6J mice were fed a diet containing 10 % energy from fat, 70 % energy from carbohydrate (35 % energy from sucrose) and 20 % energy from casein or WPI for 15 weeks. Mice fed with WPI had reduced weight gain, cumulative energy intake and dark-phase VO2 compared with casein-fed mice (P< 0·05); however, WPI intake had no significant effects on body composition, meal size/number, water intake or RER. Plasma levels of insulin, TAG, leptin, glucose and glucagon-like peptide 1 remained unchanged. Notably, the intake of WPI reduced stomach weight and both length and weight of the small intestine (P< 0·05). WPI intake reduced the gastric expression of Wingless/int-1 5a (Wnt5a) (P< 0·01) and frizzled 4 (Fzd4) (P< 0·01), with no change in the expression of receptor tyrosine kinase-like orphan receptor 2 (Ror2) and LDL receptor-related protein 5 (Lrp5). In the ileum, WPI increased the mRNA expression of Wnt5a (P< 0·01) and caused a trend towards an increase in the expression of Fzd4 (P= 0·094), with no change in the expression of Ror2 and Lrp5. These genes were unresponsive in the duodenum. Among the nutrient-responsive genes, WPI specifically reduced ileal mRNA expression of peptide YY (P< 0·01) and fatty acid transporter protein 4 (P< 0·05), and decreased duodenal mRNA expression of the insulin receptor (P= 0·05), with a trend towards a decreased expression of Na–glucose co-transporter 1 (P= 0·07). The effects of WPI on gastrointestinal Wnt signalling may explain how this protein affects gastrointestinal structure and function and, in turn, energy intake and balance.