It is unclear how timing of exercise relative to meal ingestion influences substrate balance and metabolic responses. The present study aimed to compare the effects of exercise performed before or after breakfast on fat balance and postprandial metabolism. A total of ten sedentary overweight men (aged 28·1 (sem 10·7) years, BMI 29·0 (sem 2·8) kg/m2) underwent three trials in random order involving: (1) performing no exercise (CON), or walking for 60 min at 50 % maximal O2 uptake either (2) before (Ex-Meal) or (3) after (Meal-Ex) consuming a standardised breakfast meal. In each trial an ad libitum lunch was provided 3·5 h after breakfast. Substrate utilisation was assessed by indirect calorimetry and blood was taken at regular intervals over an 8·5 h observation period. At the end of the observation period, fat balances in the Ex-Meal ( − 1043 (sem 270) kJ) and Meal-Ex ( − 697 (sem 201) kJ) trials were both significantly lower than CON (204 (sem 165) kJ) and fat balance in the Ex-Meal trial was significantly lower than in the Meal-Ex trial (all P <0·0001). Compared with the CON trial, the 8·5 h postprandial TAG response was only significantly lowered in the Ex-Meal trial ( − 17 %, P =0·025) and not in the Meal-Ex trial ( − 11 %, P =0·20). Both the Ex-Meal and Meal-Ex trials showed significantly lowered insulin responses relative to the CON trial (by 19 and 24 %, respectively, P <0·01 for both). There were no differences in lunch energy intake between trials. The present findings suggest that there may be an advantage for body fat regulation and lipid metabolism in exercising before compared with after breakfast. However, further study is needed to determine whether the present findings extend over the long term under free-living conditions.

Infant nutrition may influence eating behaviour and food preferences in later life. The present study explores whether exclusive breast-feeding duration and age at introduction of solid foods are associated with children's eating behaviour and fruit and vegetable intake at age 5 years. Data were derived from the Amsterdam Born Children and their Development study, a prospective birth cohort in the Netherlands, and included 3624 children. During infancy, data on infant nutrition were collected. Child eating behaviour (satiety responsiveness, enjoyment of food, slowness in eating and food responsiveness) was assessed with the Children's Eating Behaviour Questionnaire; and fruit and vegetable intake was calculated from a validated child FFQ. Both questionnaires were filled in by the mothers after their child turned 5 years. Exclusive breast-feeding duration was not associated with later eating behaviour, although longer exclusive breast-feeding was significantly associated with a higher vegetable intake at age 5 years. Compared with the introduction of solid foods at age 6 months, introduction before the age of 4 months was associated with less satiety responsiveness at age 5 years (β − 0·09; 95 % CI − 0·16, − 0·02). Introducing solid foods after 6 months was associated with less enjoyment of food (β − 0·07; 95 % CI − 0·12, − 0·01) and food responsiveness (β − 0·04; 95 % CI − 0·07, − 0·01). Introducing solid foods before the age of 4 months was associated with a higher fruit intake compared with introduction at 6 months. These findings suggest that prolonged breast-feeding and introduction of solid foods between 4 and 6 months may lead to healthier eating behaviour and food preferences at age 5 years.

The use of whole-room calorimetry (WRC) in young children can increase our understanding of children's energy balance. However, studies using WRC in young children are rare due to concerns about its feasibility. To assess the feasibility of WRC in young children, forty children, aged 4–6 years, were asked to follow a graded activity protocol while in a WRC. In addition, six children participated in two additional resting protocols to examine the effect of diet-induced thermogenesis on resting energy expenditure (REE) measures and the reliability of REE measurement. Refusals to participate and data loss were quantified as measures of practical utility, and REE measured after an overnight fast and after a 90-min fast were compared. In addition, both were compared to predicted BMR values using the Schofield equation. Our results showed that thirty (78·9 %) participants had acceptable data for all intensities of the activity protocol. The REE values measured after a 90-min fast (5·07 (sd 1·04) MJ/d) and an overnight fast (4·73 (sd 0·61) MJ/d) were not significantly different from each other (P= 0·472). However, both REE after an overnight fast and a 90-min fast were significantly higher than predicted BMR (3·96 (sd 0·18) MJ/d) using the Schofield equation (P= 0·024 and 0·042, respectively). We conclude that, with a developmentally sensitive approach, WRC is feasible and can be standardised adequately even in 4- to 6-year-old children. In addition, the effect of a small standardised breakfast, approximately 90 min before REE measurements, is likely to be small.

Diets high in protein have shown positive effects on short-term weight reduction and glycaemic control. However, the understanding of how dietary macronutrient composition relates to long-term risk of type 2 diabetes is limited. The aim of the present study was to examine intakes of macronutrients, fibre and protein sources in relation to incident type 2 diabetes. In total, 27 140 individuals, aged 45–74 years, from the population-based Malmö Diet and Cancer cohort, were included. Dietary data were collected with a modified diet history method, including registration of cooked meals. During 12 years of follow-up, 1709 incident type 2 diabetes cases were identified. High protein intake was associated with increased risk of type 2 diabetes (hazard ratio (HR) 1·27 for highest compared with lowest quintile; 95 % CI 1·08, 1·49; P for trend = 0·01). When protein consumption increased by 5 % of energy at the expense of carbohydrates (HR 1·20; 95 % CI 1·09, 1·33) or fat (HR 1·21; 95 % CI 1·09, 1·33), increased diabetes risk was observed. Intakes in the highest quintiles of processed meat (HR 1·16; 95 % CI 1·00, 1·36; P for trend = 0·01) and eggs (HR 1·21; 95 % CI 1·04, 1·41; P for trend = 0·02) were associated with increased risk. Intake of fibre-rich bread and cereals was inversely associated with type 2 diabetes (HR 0·84; 95 % CI 0·73, 0·98; P for trend = 0·004). In conclusion, results from the present large population-based prospective study indicate that high protein intake is associated with increased risk of type 2 diabetes. Replacing protein with carbohydrates may be favourable, especially if fibre-rich breads and cereals are chosen as carbohydrate sources.

Extreme macronutrient intakes possibly lead to different brain signalling. The aim of the present study was to determine the effects of ingesting high-protein v. high-carbohydrate food on liking and wanting task-related brain signalling (TRS) and subsequent macronutrient intake. A total of thirty female subjects (21·6 (sd 2·2) years, BMI 25·0 (sd 3·7) kg/m2) completed four functional MRI scans: two fasted and two satiated on two different days. During the scans, subjects rated all food items for liking and wanting, thereby choosing the subsequent meal. The results show that high-protein (PROT) v. high-carbohydrate (CARB) conditions were generated using protein or carbohydrate drinks at the first meal. Energy intake and hunger were recorded. PROT (protein: 53·7 (sd 2·1) percentage of energy (En%); carbohydrate: 6·4 (sd 1·3) En%) and CARB conditions (protein: 11·8 (sd 0·6) En%; carbohydrate: 70·0 (sd 2·4) En%) were achieved during the first meal, while the second meals were not different between the conditions. Hunger, energy intake, and behavioural liking and wanting ratings were decreased after the first meal (P< 0·001). Comparing the first with the second meal, the macronutrient content changed: carbohydrate − 26·9 En% in the CARB condition, protein − 37·8 En% in the PROT condition. After the first meal in the CARB condition, wanting TRS was increased in the hypothalamus. After the first meal in the PROT condition, liking TRS was decreased in the putamen (P< 0·05). The change in energy intake from the first to the second meal was inversely related to the change in liking TRS in the striatum and hypothalamus in the CARB condition and positively related in the PROT condition (P< 0·05). In conclusion, wanting and liking TRS were affected differentially with a change in carbohydrate or protein intake, underscoring subsequent energy intake and shift in macronutrient composition.

Objective estimates of activity patterns and energy expenditure (EE) are important for the measurement of energy balance. The Intelligent Device for Energy Expenditure and Activity (IDEEA) can estimate EE from the thirty-five postures and activities it can identify and record. The present study evaluated the IDEEA system's estimation of EE using whole-body indirect calorimetry over 24 h, and in free-living subjects using doubly-labelled water (DLW) over 14 d. EE was calculated from the IDEEA data using calibration values for RMR and EE while sitting and standing, both as estimated by the IDEEA system (IDEEAest) and measured by indirect calorimetry (IDEEAmeas). Subjects were seven females and seven males, mean age 38·1 and 39·7 years, mean BMI 25·2 and 26·2 kg/m2, respectively. The IDEEAest method produced a similar estimate of EE to the calorimeter (10·8 and 10·8 MJ, NS), while the IDEEAmeas method underestimated EE (9·9 MJ, P < 0·001). After removing data from static cycling, which the IDEEA was unable to identify as an activity, both the IDEEAest and IDEEAmeas methods overestimated EE compared to the calorimeter (9·9 MJ, P < 0·001; 9·1 MJ, P < 0·05 and 8·6 MJ, respectively). Similarly, the IDEEA system overestimated EE compared to DLW over 14 d; 12·7 MJ/d (P < 0·01), 11·5 MJ/d (P < 0·01) and 9·5 MJ/d for the IDEEAest, IDEEAmeas and DLW, respectively. The IDEEA system overestimated EE both in the controlled laboratory and free-living environments. Using measured EE values for RMR, sitting and standing reduced, but did not eliminate, the error in estimated EE.

Early feeding experiences, e.g. related to milk feeding, can affect later food and taste preferences. However, consequences of breast-feeding on taste acceptance are under-investigated. The objective of the present study was to examine the impact of exclusive breast-feeding duration (DEB) on taste acceptance at 6 and 12 months in the same infants (n 122). Mothers recorded the DEB. Acceptance of solutions of each of the five basic tastes relative to water was evaluated in the laboratory at 6 and 12 months by the ingestion ratio (IR). Kendall correlations were calculated between the DEB and the IR. Only 16 % completed at least 6 months of exclusive breast-feeding; 79 % had begun complementary feeding by 6 months. At 6 months, infants preferred sweet, salty and umami solutions over water and were indifferent to sour and bitter solutions. The longer an infant was breast-fed, the more s/he accepted the umami solution at 6 months. At 12 months, infants preferred sweet and salty solutions over water and were indifferent to sour, bitter and umami solutions. The relationship between the DEB and acceptance of the umami solution was not observed at 12 months. No relationship was observed between the DEB and sweet, salty, sour and bitter taste acceptance at 6 or 12 months. The association between the DEB and umami taste acceptance at 6 months may relate to the higher glutamate content of human milk compared with formula milk. Beyond the acknowledged metabolic benefits of breast-feeding, this suggests that prolonged breast-feeding could also be associated with an impact on sensory preference at the beginning of complementary feeding.

The aim of the present study was to investigate whether the impairments in cognitive function observed in unsupported dieting are related to compromised Fe status. During a non-clinical intervention, overweight participants (age: 18–45 years, BMI: 25–30 kg/m2) either participated in a commercially available weight-loss regimen (n 14), dieted without support (n 17) or acted as a non-dieting control group (n 14) for a period of 8 weeks. Measurements of cognitive function and blood chemistry were taken at a pre-diet baseline, after 1 week and 8 weeks of dieting. After 1 week, unsupported dieters displayed impaired verbal memory, executive function and slower reaction speeds than the other two groups, this difference disappearing by the end of the study. There were no significant group-related changes in blood chemistry over the course of the study, although there were group-related changes in a number of self-reported food-related cognitions. In conclusion, impaired cognition among unsupported dieters is not due to compromised Fe status and is most likely to result from psychological variables.

The aim of the present study was to validate a food photograph album (FPA) as a tool to visually estimate food amounts, and to compare this estimation with that attained through the use of measuring cups (MC) and food models (FM). We tested 163 foods over fifteen sessions (thirty subjects/session; 10–12 foods presented in two portion sizes, 20–24 plates/session). In each session, subjects estimated food amounts with the assistance of FPA, MC and FM. We compared (by portion and method) the mean estimated weight and the mean real weight. We also compared the percentage error estimation for each portion, and the mean food percentage error estimation between methods. In addition, we determined the percentage error estimation of each method. We included 463 adolescents from three public high schools (mean age 17·1 (sd 1·2) years, 61·8 % females). All foods were assessed using FPA, 53·4 % of foods were assessed using MC, and FM was used for 18·4 % of foods. The mean estimated weight with all methods was statistically different compared with the mean real weight for almost all foods. However, a lower percentage error estimation was observed using FPA (2·3 v. 56·9 % for MC and 325 % for FM, P< 0·001). Also, when analysing error rate ranges between methods, there were more observations (P< 0·001) with estimation errors higher than 40 % with the MC (56·1 %), than with the FPA (27·5 %) and FM (44·9 %). In conclusion, although differences between estimated and real weight were statistically significant for almost all foods, comparisons between methods showed FPA to be the most accurate tool for estimating food amounts.

Numerous studies have shown that people adjust their intake directly to that of their eating companions. A potential explanation for this modelling effect is that the eating behaviour of others operates as an external eating cue that stimulates food intake. The present study explored whether this cue-reactive mechanism can account for modelling effects on intake. It was investigated whether attentional bias towards dynamic eating cues and impulsivity would influence the degree of modelling. Participants completed one individual session and one session in which an experimental confederate accompanied them. In the first session, eye movements were recorded as an index of attentional bias to dynamic eating cues. In addition, self-reported impulsivity and response inhibition were assessed. The second session employed a between-participants design with three experimental conditions in which participants were exposed to a same-sex confederate instructed to eat nothing, a low or a large amount of M&Ms. A total of eighty-five young women participated. The participants' self-reported impulsivity determined the occurrence of modelling; only low-impulsive women adjusted their intake to that of their eating companion. Attention towards eating cues and response inhibition, however, did not moderate modelling of food intake. The present study suggests that cue-reactive mechanisms may not underlie modelling of food intake. Instead, the results emphasise the importance of social norms in explaining modelling effects, whereas it is suggested that the degree of impulsivity may play a role in whether or not women adhere to the intake norms set by their eating companion.