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.

Most human intervention studies have examined the effects on a subset of risk factors, some of which may require long-term exposure. The plasma proteome may reflect the underlying changes in protein expression and activation, and this could be used to identify early risk markers. The aim of the present study was to evaluate the impact of regular fish intake on the plasma proteome. We recruited thirty healthy men aged 40 to 70 years, who were randomly allocated to a daily meal of chicken or trout raised on vegetable or marine feeds. Blood samples were collected before and after 8 weeks of intervention, and after the removal of the twelve most abundant proteins, plasma proteins were separated by two-dimensional gel electrophoresis. Protein spots < 66 kDa with a pI >4·3 visualised by silver staining were matched by two-dimensional imaging software. Within-subject changes in spots were compared between the treatment groups. Differentially affected spots were identified by matrix-assisted laser desorption ionisation-time of flight/time of flight MS and the human Swiss-Prot database. We found 23/681 abundant plasma protein spots, which were up- or down-regulated by the dietary treatment (P< 0·05, q< 0·30), and eighteen of these were identified. In each trout group, ten spots differed from those in subjects given the chicken meal, but only three of these were common, and only one spot differed between the two trout groups. In both groups, the affected plasma proteins were involved in biological processes such as regulation of vitamin A and haem transport, blood fibrinolysis and oxidative defence. Thus, regular fish intake affects the plasma proteome, and the changes may indicate novel mechanisms of effect.

Little is known about the macronutrient intake status of older Chinese people. The present study evaluated the macronutrient intake status of older Chinese people (aged ≥ 60 years), investigated whether they had intake levels that met the Dietary Reference Intakes (DRI), and explored the associations between macronutrient intakes and age groups, sex, education levels, work status, BMI groups, urbanicity levels and four socio-economic regions of China (Northeast, East Coast, Central and Western). Dietary intake data of 2746 older Chinese with complete dietary intake data in the Longitudinal China Health and Nutrition Survey (2009 wave) carried out across four diverse regions were analysed. Dietary intake data were obtained by interviews using 24 h recalls over three consecutive days. The MUFA:SFA ratios were calculated based on the Chinese Food Composition Table. Less than one-third of the older Chinese people included in the present study had intake levels meeting the adequate intake for carbohydrate-energy and fat-energy; less than one-fifth had intake levels meeting the recommended nutrient intake for protein-energy; and more than half of the older people had fat-energy intakes higher than the DRI. There were strong associations between the proportions of energy from the three macronutrients and education levels, urbanicity levels and the four socio-economic regions of China, with older people living in the East Coast region having different patterns of macronutrient-energy intakes when compared with those living in the other three regions. Macronutrient intakes across different urbanicity levels in the four regions revealed considerable geographical variations in dietary patterns, which will affect the risk factors for non-communicable diseases. Clinical interventions and public health policies should recognise these regional differences in dietary patterns.

It is often assumed that some individuals reliably increase energy intake (EI) post-exercise (‘compensators’) and some do not (‘non-compensators’), leading researchers to examine the characteristics that distinguish these two groups. However, it is unclear whether EI post-exercise is stable over time. The present study examined whether compensatory eating responses to a single exercise bout are consistent within individuals across three pairs of trials. Physically inactive, overweight/obese women (n 28, BMI 30·3 (sd 2·9) kg/m2) participated in three pairs of testing sessions, with each pair consisting of an exercise (30 min of moderate-intensity walking) and resting testing day. EI was measured using a buffet meal 1 h post-exercise/rest. For each pair, the difference in EI (EIdiff= EIex− EIrest) was calculated, where EIex is the EI of the exercise session and EIrest is the EI of the resting session, and women were classified as a ‘compensator’ (EIex>EIrest) or ‘non-compensator’ (EIex≤ EIrest). The average EI on exercise days (3328·0 (sd 1686·2) kJ) was similar to those on resting days (3269·4 (sd 1582·4) kJ) (P= 0·67). Although EI was reliable within individuals across the three resting days (intraclass correlation coefficient (ICC) 0·75, 95 % CI 0·60, 0·87; P< 0·001) and three exercise days (ICC 0·83, 95 % CI 0·70, 0·91; P< 0·001), the ICC for EIdiff across the three pairs of trials was low (ICC 0·20, 95 % CI − 0·02, 0·45; P= 0·04), suggesting that compensatory eating post-exercise is not a stable construct. Moreover, the classification of ‘compensators’/‘non-compensators’ was not reliable (κ =− 0·048; P= 0·66). The results were unaltered when ‘relative’ EI was used, which considers the energy expenditure of the exercise/resting sessions. Acute compensatory EI following an exercise bout is not reliable in overweight women. Seeking to understand what distinguishes ‘compensators’ from ‘non-compensators’ based on a single eating episode post-exercise is not justified.

Diet is a strong moderator of systemic inflammation, an established risk factor for colorectal cancer (CRC). The dietary inflammatory index (DII) measures the inflammatory potential of individuals' diets. The association between the DII and incident CRC was examined, using the National Institutes of Health–American Associations of Retired Persons Diet and Health Study individuals (n 489 422) aged 50–74 years at recruitment, starting between 1995–6, and followed for a mean of 9·1 (sd 2·9) years. Baseline data from a FFQ were used to calculate the DII; higher scores are more pro-inflammatory, and lower scores are more anti-inflammatory. First, primary CRC diagnoses were identified through linkage to state cancer registries. Anatomic location and disease severity also were examined. Cox proportional hazards models estimated CRC hazard ratios (HR) and 95 % CI using quartile 1 as the referent. DII quartile 4 compared to quartile 1 was associated with CRC risk among all subjects (HR 1·40, 95 % CI 1·28, 1·53; P for trend < 0·01). Statistically significant associations also were observed for each anatomic site examined, for moderate and poorly differentiated tumours, and at each cancer stage among all subjects. Effects were similar when stratified by sex; however, results were statistically significant only in males. The only result reaching statistical significance in females was risk of moderately differentiated CRC tumours (DII quartile 4 v. quartile 1 HR 1·26, 95 % CI 1·03, 1·56). Overall, the DII was associated with CRC risk among all subjects. The DII may serve as a novel way to evaluate dietary risk for chronic disorders associated with inflammation, such as CRC.

The prevalence of dietary supplement use varies largely among populations, and previous studies have indicated that it is high in the Danish population compared with other European countries. The diversity in supplement use across countries indicates that cultural and environmental factors could influence the use of dietary supplements. Only few studies investigating the use of dietary supplements have been conducted in the Danish population. The present cross-sectional study is based on 54 948 Danes, aged 50–64 years, who completed self-administrated questionnaires on diet, dietary supplements and lifestyle between 1993 and 1997. A health index including smoking, physical activity, alcohol and diet, and a metabolic risk index including waist circumference, urinary glucose and measured hypertension were constructed. Logistic regression was used to investigate these determinants in relation to the intake of dietary supplements. We found that 71 % of the participants were dietary supplement users; female sex, older age groups and higher educated participants were more likely to be users of any dietary supplements. One additional point in the health index was associated with 19, 16 and 9 % higher likelihood of being user of any, more common and less common supplements, respectively. In the metabolic risk index, one additional point was associated with 17 and 16 % lower likelihood of being user of any supplement and more common supplements, respectively. No significant association was found for less common supplement use. In conclusion, those with the healthiest lifestyle were more likely to use dietary supplements. Thus, lifestyle and dietary composition should be considered as confounders on supplement use and health outcomes.

This study assesses the levels of fats, including trans-fatty acids, and salt in common takeaway fast foods in a deprived urban municipality in the West Midlands, England, and implications in the context of the spatial distribution of fast food takeaways. The results of the compositional analysis of over 250 take-out foods were compared with established and derived standards. About 70 % of products exceeded the recommendation that a meal should contain less than 30 % of a Guideline Daily Amount (GDA). More than half of them exceeded 50 % GDA for at least one metric, including 81 % of all analyses for SFA. And 17 % of samples exceeded the GDA for SFA, including each of two meals that contained about twice the GDA. Over 30 % samples exceeded the children's GDA for total fat or SFA. 27 % of salt analyses exceeded the GDA. People in Sandwell are exposed to large portion sizes and high levels of fats and salt in takeaway foods, with levels in some foods having increased since 2010. Given this population's limited options to break out of a highly compromising environment of living simultaneously in a ‘swamp’ of unhealthy, readily accessible and cheap takeaways, and a ‘desert’ of healthy options, an immediate and innovative package of interventions is required.

Higher dietary energy density (DED) has been reported to be associated with weight gain, obesity and poorer dietary quality, yet nationally representative estimates that would allow tracking of secular trends and inter-country comparisons are limited. The aims of the present study were to calculate DED estimates for the Irish population and to identify dietary determinants of DED. Weighed/semi-weighed food records from three cross-sectional surveys (the National Children's Food Survey, the National Teens’ Food Survey and the National Adult Nutrition Survey) were collated to estimate habitual dietary intakes for a nationally representative sample of the Irish population, aged 5–90 years (n 2535). DED estimates, calculated using the total diet method, the food only method and a novel method, including foods and solids in beverages, were 3·70 (sd 1·09), 7·58 (sd 1·72) and 8·40 (sd 1·88) kJ/g, respectively. Determinants of DED did not vary by the calculation method used. Variation in the intakes of fruit, vegetables and sugar-sweetened beverages (SSB) across consumer groups contributed to the largest variance in DED estimates, followed by variation in the intakes of potatoes, fresh meat, bread, chips, ready-to-eat breakfast cereals, and confectionery. DED estimates were inversely associated with age group and consistently lower for females than for males. The inverse association of DED with age group was explained by higher intakes of vegetables, fruit, fish, potatoes, fresh meat and brown bread and lower intakes of SSB, chocolate confectionery, ready-to-eat breakfast cereals and savoury snacks in older age groups. Females consumed, on average, 1·5 times more fruit and vegetables combined when compared with males, largely explaining the sex differences in DED estimates. Current DED estimates for adults were similar to those calculated in a previous survey, carried out 10 years earlier. These estimates and determinants serve as a baseline for comparison for other works and public health campaigns.

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.