DE-PASS best evidence statement (BESt): determinants of adolescents' device-based physical activity and sedentary behaviour in settings: a systematic review and meta-analysis.

BACKGROUND: Although physical activity (PA) is associated with significant health benefits, only a small percentage of adolescents meet recommended PA levels. This systematic review with meta-analysis explored the modifiable determinants of adolescents' device-based PA and/or sedentary behaviour (SB), evaluated in previous interventions and examined the associations between PA/SB and these determinants in settings. METHODS: A search was conducted on five electronic databases, including papers published from January 2010 to July 2023. Randomized Controlled Trials (RCTs) or Controlled Trials (CTs) measuring adolescents' device-based PA/SB and their modifiable determinants at least at two time points: pre- and post-intervention were considered eligible. PA/SB and determinants were the main outcomes. Modifiable determinants were classified after data extraction adopting the social-ecological perspective. Robust Bayesian meta-analyses (RoBMA) were performed per each study setting. Outcomes identified in only one study were presented narratively. The risk of bias for each study and the certainty of the evidence for each meta-analysis were evaluated. The publication bias was also checked. PROSPERO ID: CRD42021282874. RESULTS: Fourteen RCTs (eight in school, three in school and family, and one in the family setting) and one CT (in the school setting) were included. Fifty-four modifiable determinants were identified and were combined into 33 broader determinants (21 individual-psychological, four individual-behavioural, seven interpersonal, and one institutional). RoBMAs revealed none or negligible pooled intervention effects on PA/SB or determinants in all settings. The certainty of the evidence of the impact of interventions on outcomes ranged from very low to low. Narratively, intervention effects in favour of the experimental group were detected in school setting for the determinants: knowledge of the environment for practicing PA, d = 1.84, 95%CI (1.48, 2.20), behaviour change techniques, d = 0.90, 95%CI (0.09, 1.70), choice provided, d = 0.70, 95%CI (0.36, 1.03), but no corresponding effects on PA or SB were found. CONCLUSIONS: Weak to minimal evidence regarding the associations between the identified modifiable determinants and adolescents' device-based PA/SB in settings were found, probably due to intervention ineffectiveness. Well-designed and well-implemented multicomponent interventions should further explore the variety of modifiable determinants of adolescents' PA/SB, including policy and environmental variables.

Associations between chronotype, diet quality and timing of energy intake in Portuguese children and adolescents: The potential role of summer holidays.

Later chronotypes may be associated with lower diet quality and later timing of energy intake in paediatric age. Period of data collection of these variables may affect these parameters and inter-relationship. We aimed to assess the cross-sectional association of chronotype with a diet quality score (HEI) and caloric midpoint (time of achieving 50% of total daily energy intake), considering summer holidays, using data from the National Food, Nutrition and Physical Activity Survey 2015-2016 for 578 participants (6-14 years of age). Chronotype was estimated by the midpoint of sleep and categorized as Early, Intermediate and Late, using physical activity diaries, while outcomes using two food diaries/24 h recalls. Associations of chronotype with outcomes were assessed by linear regressions adjusted for sex, age, parental education (model 1), BMI, sports practice (model 2), and summer holidays (no/yes) (model 3). In model 2, a Late vs. Early chronotype was negatively associated with HEI (߈ = -0.74; 95% CI: -1.47, -0.07) and positively with caloric midpoint (߈ = 0.35; 95% CI: 0.02, 0.69). However, associations lost significance in model 3. The association between chronotype and dietary habits may be benefit from being studied considering school terms and summer holidays. Future larger prospective studies are needed to clarify the role of summer holidays on this inter-relationship.

Sleep duration is associated with appetitive traits in school-age years - results from the Generation XXI birth cohort.

Sleep may influence appetite regulation through physiological and neurocognitive pathways. However, the association between sleep and appetite in childhood has been scarcely reported, particularly using a prospective design. We aimed to test associations between sleep duration at 7 years of age (y) and appetitive traits at both 7 and 10 y. Participants are from the population-based birth cohort Generation XXI (Porto, Portugal), at 7 (n = 2437) and 10 y (n = 1938) follow-ups. Data on sleep was gathered at 7 y and, considering bedtime and get-up time, total mean sleep duration was calculated and further categorized according to the 10th and 90th percentiles. Appetitive traits were assessed at 7 and 10 y using the parent-reported Children's Eating Behaviour Questionnaire. Associations were tested through Generalized Linear Models (co-variates: child's sex; maternal age, education and pre-pregnancy body mass index at 7 y). At 10 y, associations were further adjusted for the respective appetitive trait at 7 y. Children slept a mean of 10.2 h/night, and 13% and 9% slept ≤9.5 and ≥ 11.0 h/night at 7 y, respectively. For each additional hour in sleep duration, children scored 0.078 (99%CI: -0.145; -0.011) lower on Food Responsiveness, 0.065 (99%CI: -0.129; -0.002) lower on Emotional Undereating and 0.096 (99%CI: -0.161; -0.032) lower on Food Fussiness. Lastly, children sleeping ≤9.5 h/night scored higher on Food Responsiveness (ß = 0.145 99%CI: 0.020; 0.271); while those sleeping ≥11.0 h/night scored lower on Food Fussiness (ß = -0.255 99%CI: -0.370; -0.079). No significant prospective associations were found. In conclusion, in 7 y children, sleep duration was cross-sectionally associated with lower scores on food approach (Food Responsiveness) and avoidant traits (Emotional Undereating and Food Fussiness). However, the magnitude of the associations was small and further studies are warranted.

Longitudinal tracking of diet quality from childhood to adolescence: The Interplay of individual and sociodemographic factors.

This study aimed to examine diet tracking from childhood to adolescence, using 4 time-points, and the influence of socioeconomic and individual characteristics in this transition. The sample included 6893 children from the Portuguese birth cohort Generation XXI with complete information on Food Frequency Questionnaire in at least one of the considered follow-ups. A Healthy Eating Index (HEI), previously developed to assess adherence to WHO's dietary recommendations, was applied at all ages (4, 7, 10 and 13y). The intraclass correlation coefficient (ICC) was used to analyse the tracking of diet quality. Linear mixed-effect models were performed to estimate the association of the child's socioeconomic and individual characteristics with the HEI score and respective trajectories over time. The overall diet quality decreased from childhood (22.2 ± 3.6 at 4y) to adolescence (18.2 ± 3.9 at 13y), with moderate tracking (ICC = 0.53), showing that children who start a healthy diet earlier might have a better diet quality as time goes by. Children of older mothers (ß = 0.079, 95%CI = 0.061-0.097) and with higher education (ß = 0.203, 95%CI = 0.178-0.229) and a higher household monthly income (ß = 0.024,95%CI = 0.007-0.041) had a higher diet quality over time. Besides family characteristics, the child's sedentary activities (ß = -0.009, 95%CI = -0.014--0.003) negatively influence diet quality throughout life. In contrast, being a girl (ß = -0.094, 95%CI = -0.132--0.056) and having higher sleep duration (ß = 0.039, 95%CI = 0.015-0.064) are associated with a higher diet quality over time. The presence of dietary tracking from childhood to adolescence implies that promoting healthy eating habits during the first years of life is crucial for a healthier diet quality during late childhood and early adolescence, focusing on maternal and individual child characteristics.

Sleep timing behaviour, sleep duration and adherence to obesogenic dietary patterns from pre-school to school age: results from the Portuguese birth cohort Generation XXI.

In an obesogenic environment, short sleeping may increase opportunistic eating. The timing of sleep might also influence the drive to eat. This study investigated the prospective association of sleep timing and duration with diet in 5286 children from the Portuguese birth cohort Generation XXI, evaluated at 4 and 7 years of age. At 4 years, sleep duration was categorised into ≤10 and >10 h. Four sleep timing categories were generated based on the median split for sleep-onset and -offset times: 'Early Sleep-Early Wake'; 'Early Sleep-Late Wake'; 'Late Sleep-Early Wake'; 'Late Sleep-Late Wake'. At 7 years, diet was obtained by a food frequency questionnaire and three dietary patterns were included: 'Healthier', 'Energy-Dense Foods (EDF)' and 'Snacking'. The Healthy Eating Index was used to evaluate diet quality. Multinomial logistic regression models and generalised linear models were performed. Children who had a late sleep, independently of the time of waking up, had higher odds of following the 'EDF' pattern, compared with the 'Healthier'. Boys who had late sleep and/or late wake had also higher odds of following the 'Snacking' pattern and had poorer diet quality. In both sexes, a late sleep or late wake were associated with a lower diet quality, compared to the group 'Early Sleep-Early Wake', and independently of nap behaviour. In boys, shorter sleep duration was associated with a poorer diet. In conclusion, pre-schoolers with late bedtimes or wake-up times have worse dietary patterns and poorer diet quality at the age of 7 years, which seems to be independent of sleep duration.

Methodological approaches for the assessment of bisphenol A exposure.

Bisphenol A (BPA) is an endocrine disruptor used in food contact materials, by the application of polycarbonate plastics and epoxy resins. The main objective of this study is to compare the estimate of daily BPA exposure at 13 years of age and in the adult Portuguese population, using different methodological approaches, and assess the associations between this exposure and sociodemographic characteristics. METHODOLOGY: Cross-sectional data of 13-years follow-up from a population-based birth cohort Generation XXI (GXXI) (n = 2804) and from the National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016) (n = 3845, ≥18 years old) was used. Dietary information was collected through three food diaries for adolescents and two non-consecutive 24-hour-recalls for adults. To estimate the daily exposure to BPA, three methodological approaches were used. "Food groups attribution" merged the food consumption data with the concentration of BPA in food groups. "Regression tree model" and "random forest" combined food consumption information with urinary BPA, measured in a subsample of 24-hour urine (in adolescents n = 216, and in adults n = 82), both used to predict BPA exposure in the remaining sample. The fit-index of the methodologies was assessed through the root mean square error (RMSE), mean absolute error (MAE) and Spearman correlation coefficient (ρ). Associations between BPA exposure and sociodemographic variables were tested by linear regression models, adjusted for sex, age groups (in adults) and educational level. Tolerable Daily Intake (TDI) of 0.2 ng/kg body weight (bw), recently proposed by the European Food Safety Authority (EFSA), was used for the risk characterization of BPA exposure. RESULTS: The "random forest" was found as the best methodology to estimate the daily BPA exposure (adolescents: RMSE = 0.989, MAE = 0.727, ρ = 0.168; adults: RMSE = 0.193, MAE = 0.147, ρ = 0.250). The median dietary BPA exposure, calculated by "food groups attribution", was 79.1 and 46.1 ng/kg bw/day for adolescents and adults, respectively, while "random forest" estimated a BPA exposure of 26.7 and 38.0 ng/kg bw/day. 99.9% of the Portuguese population presented a daily exposure above TDI. Male adolescents, females and higher educated adults, were those more exposed to BPA. CONCLUSIONS: The estimated daily BPA exposure strongly depends on the methodological approach. Food groups attribution may overestimate the exposure while the random forest appears to be a better methodological approach to estimate BPA exposure. Nevertheless, for all methods, the Portuguese population presented an unsafe BPA exposure by largely exceeding the safe levels proposed by EFSA.

Effect of the food processing degree on cardiometabolic health outcomes: A prospective approach in childhood.

BACKGROUND & AIMS: Ultra-processed foods (UPF) consumption has increased greatly over the last decades but its impact on health remains unclear. This study aimed to evaluate the prospective effect of different degrees of food processing on children's cardiometabolic profile. METHODS: Children from the Portuguese population-based birth cohort Generation XXI evaluated at 7 and 10 years of age (y), with dietary information at 7 y and anthropometric measurements at 10 y, were included in the present study (n = 3034). Dietary data were collected by 3-day food diaries and all reported food items were classified according to the degree of processing using the NOVA classification system. The daily consumption of the NOVA classification groups was calculated (in grams, as a proportion of total grams and total energy intake). The cardiometabolic outcomes included were serum markers [fasting glucose, insulin, blood lipids], anthropometric measurements [body mass index (BMI) and waist circumference (WC)], body composition [fat-free mass (FFM) and fat mass (FM)] and blood pressure (BP). Age- and sex-specific sample z-scores were obtained for all outcomes. Principal Component Analysis was used to identify a potential cluster of cardiovascular risk factors. Generalized linear models were fitted to evaluate the association between the consumption according to the processing degree (as absolute gram intake) and the individual cardiometabolic risk factors and cluster, adjusted for child's sex, maternal age and education and remaining NOVA groups. A mediation role of children's BMI in the previous analysis were tested. RESULTS: At 7 y, the daily median consumption of un/minimally processed, processed and UPF was 1210 g, 113 g and 433 g (68%, 6% and 25% of the total grams, as well as 51%, 15% and 31% of the total energy intake, respectively). After adjustment, an increase of 100 g in the consumption of un/minimally processed at 7 y was associated with a lower BMI (߈ = -0.028; 95%CI: -0.043; -0.014), WC (߈ = -0.020; 95%CI: -0.032; -0.008), FM (߈ = -0.023; 95%CI: -0.035; -0.011), insulin (߈ = -0.022; 95%CI: -0.036; -0.008) and BP (systolic BP: ߈ = -0.014; 95%CI: -0.025;-0.004; diastolic BP: ߈ = -0.013; 95%CI: -0.020;-0.005), at 10 y. BMI was a mediator between the consumption of un/minimally processed foods and BP. Positive associations were found between consumption of processed foods and the cluster 'higher blood pressure', while an inverse association was described between un/minimally processed and the cluster 'higher blood pressure'. No significant associations were found between the UPF consumption and any cardiometabolic outcomes. CONCLUSIONS: High consumption of unprocessed or minimally processed foods has a favourable effect on later children's cardiometabolic health, namely lower body weight and body fat, lower waist circumference, blood pressure insulin serum levels.

Association of dietary macronutrient intake with adiposity during childhood according to sex: Findings from the generation XXI birth cohort.

BACKGROUND/OBJECTIVES: Few studies have assessed the independent and longitudinal effects of each macronutrient intake on adiposity throughout childhood. We aimed to prospectively assess the independent associations between each macronutrient intake at 4, 7, and 10 years (protein, carbohydrates, fat, and fibre) and each measure of adiposity from 7 to 10 years of age by sex. METHODS: Data from the population-based birth cohort Generation XXI was used (n = 3999). At 4, 7, and 10 years old, dietary, anthropometric and sociodemographic data were collected. The dietary intake of the children was evaluated by a validated food frequency questionnaire. Age- and sex-specific body mass index z-scores (zBMI), percentage of body fat (%FM) from bio-impedance, and waist-to-hip ratio (Whr) were used as measures of adiposity. Path analysis tested the independent associations between each macronutrient intake (protein, carbohydrates, fat, and fibre) and each measure of adiposity from 7 to 10 years of age. RESULTS: In fully adjusted models, an increase in energy from fibre intake at the age of 7 was associated with lower zBMI at the same age (ß = -0.073; 95%CI [-0.127,-0.019]) and at 10 years (ß = -0.083; 95%CI [-0.137,-0.029]). Similar results were found for %FM and Whr, and in each sex separately. At the age of 10, an increase in energy from fibre intake was associated with lower %FM and Whr, while an increase in energy from protein was associated with an increase in Whr (ß = 0.061; 95%CI [0.014, 0.107]). CONCLUSIONS: Our study supports the protective effect of fibre intake on adiposity development during childhood in both sexes.

Risk characterization of dietary acrylamide exposure and associated factors in the Portuguese population.

Acrylamide exposure, mainly resulting from food cooking and processing, has been associated with a higher risk of health problems, due to genotoxic effects. This study aims to estimate acrylamide dietary exposure of the Portuguese population and its associated factors. Dietary data collected through 2 non-consecutive 24 hour recalls or food diaries from a representative sample of the Portuguese population from the National Food, Nutrition and Physical Activity Survey was used (n = 5811; 3-84 years). Occurrence data of acrylamide in food were obtained from EFSA. The margins of exposure (MOE) were calculated for peripheral neuropathy and neoplastic effects. The association between acrylamide and socio-demographic characteristics was estimated through linear regression models. For the total population, the estimated median daily dietary exposure per body weight to acrylamide was 0.38 µg/kg/day, ranging from 0.14 to 0.88 µg/kg/day for the 5th and 95th percentile, respectively. Children aged between 1-2 years had the highest acrylamide exposure (median 0.75 µg/kg/day, 95th percentile 1.41 µg/kg/day). For the peripheral neuropathy and neoplastic effects, the median MOE estimated was 1140 and 451, respectively. Men compared to women had a higher acrylamide dietary exposure, as well as smokers compared to non-smokers. Elderly and less educated individuals were inversely associated with acrylamide exposure. 'Bread and rusks' (24.2%) were the main source of acrylamide, followed by 'coffee' (21.3%). The current dietary exposure to acrylamide in the Portuguese population is of concern mainly regarding neoplastic effects. Our results point to the need to reduce exposure to acrylamide, especially in men, young children, higher educated individuals and smokers.

Interaction effects of socio-economic position in the association between eating location and diet quality in Portuguese children and adolescents: results from the National Food, Nutrition and Physical Activity Survey 2015-2016.

This study aims to evaluate the interaction effect of socio-economic environment (SEE) in the relationship between the eating location (EL) and diet quality, in children and adolescents. Data included Portuguese children and adolescents (3-17 years) from a National Dietary Survey Sample (IAN-AF 2015/2016, n 987). Dietary intake was obtained by 2-d food diaries (children) or 2-24-h-recall (adolescents). Participants were classified into four groups of EL: 'Home', 'Other homes', 'School' and 'Restaurants'. Diet quality was measured as a higher adherence to a healthy eating pattern. A previous developed socio-economic classification was used, and participants were grouped as belonging to a low socio-economic environment (LSE) or middle-high socio-economic environment (MHSE). Linear regression models were used to evaluate the association between EL and diet quality, stratified by the SEE. A statistically significant interaction effect was found (P < 0·01) for the SEE in the association between EL and diet quality. After adjustment for potential confounders, in LSE, participants belonging to 'Other homes' (ß = -2·07; 95 % CI:-3·70, -0·44) and 'Restaurants' (ß = -3·31; 95 % CI: -5·08, -1·54) had lower scores in the diet quality score, comparing to 'Home'. In MHSE, comparing with 'Home', 'Restaurants' showed lower diet quality (ß = -1·56; 95 % CI:-2·65, -0·48), while the 'School' had better diet quality (ß = 0·90; 95 % CI: 0·16, 1·64). The SEE influences the association between EL and diet quality and, belonging to more disadvantaged SEE, might represent a higher risk of unhealthy eating habits when eating out-of-home.

Longitudinal bidirectional relationship between children's appetite and diet quality: A prospective cohort study.

This study explored the relationship between eating behaviours and diet quality, from 7 to 10y. The sample included 3879 children evaluated, from the Portuguese birth cohort Generation XXI, with complete information on Food Frequency Questionnaire (FFQ) and the Children Eating Behaviour Questionnaire (CEBQ). A healthy eating index (HEI) (range: 9-31) was developed to evaluate the child's diet quality. The eight CEBQ's eating behaviours were included in the analysis. Generalised linear models were used to estimate the associations. Adjusted structural equation modelling was performed to study the direction of the associations. Eating behaviours measured at age 7y tracked to age 10y. A bidirectional inverse association between the food fussiness trait and diet quality was found, with a similar magnitude (p < 0.001), thus a higher score on food fussiness predicted a lower quality of the diet. A higher HEI score at 7y was associated with lower satiety responsiveness at 10y (ßstandardized = -0.039), and a higher HEI score at age 10y was associated with higher enjoyment of food at 7y (ßstandardized = 0.046). Eating behaviours were linked to diet quality in children with high enjoyment of food and low food fussiness at age 7y linked to a high-quality diet at 10y. In addition, children with high-quality diets at 7y were more likely to have lower food fussiness and satiety responsiveness at 10y. Given the stability of eating behaviours and the bidirectional nature of effects between eating behaviours and dietary quality in the long term, tailored interventions may be needed to encourage the acquisition of healthy eating behaviours and habits in early life.

Is the association between dietary patterns and cognition mediated by children's adiposity? A longitudinal approach in Generation XXI birth cohort.

BACKGROUND/AIMS: There is a consistent body of evidence on the association between single nutrients and cognition, but the role of a healthful dietary pattern on cognition in children has been seldomly studied. This study aims to assess the association between dietary patterns at 4 years (y) and cognitive abilities at 10-13y and examine whether adiposity mediated these associations. METHODS: This study used data from a sub-sample of the population-based birth cohort Generation XXI, with complete information on diet and cognition (n = 3575). At 4y, data on dietary intake was collected by a validated food frequency questionnaire and dietary patterns were derived by latent class analysis, namely Energy-dense food (EDF) pattern, Snacking pattern and Healthier pattern (Reference). At 10-13y, the Portuguese Version of the Wechsler Intelligence Scale for Children®-Third Edition was administered by trained psychologists and age-adjusted composite scores were computed: a Full-Scale Intelligence Quotient (IQ), plus a Verbal IQ, Performance IQ and Processing Speed IQ. Age- and sex-specific body mass index (BMI) z-scores, body fat percentage from bioimpedance, and waist-to-weight ratio and waist-to-hip ratio were used as measures of adiposity. Regression coefficients and 95% confidence intervals (CI) were computed using linear regression models (adjusted for maternal age and education, pre-pregnancy BMI, smoking and alcohol intake during pregnancy, child's sex, birthweight, exclusive breastfeeding duration and having siblings at 4y). Mediation analysis was conducted using path analysis. RESULTS: After adjustment, children classified in the EDF or a Snacking patterns at 4y were more likely to have lower scores on total IQ (ß = -0.116; 95%CI:-0.192,-0.039 and ß = -0.148; 95%CI -0.252,-0.044, respectively), Verbal IQ (ß = -0.104; 95%CI -0.177, -0.031 and ß = -0.163; 95%CI -0.262,-0.064, respectively) and Performance IQ (ß = -0.116 95%CI -0.193,-0.040 and ß = -0.147; 95%CI -0.250,-0.042, respectively) at 10-13y, when compared to those classified in the Healthier pattern. None of the adiposity measures seemed to explain the associations between dietary patterns and IQ. CONCLUSION: This study supports that early unhealthy dietary patterns were associated with lower child's cognitive ability, but this effect did not seem to be mediated by adiposity.

Dietary Patterns and Oral Health Behaviours Associated with Caries Development from 4 to 7 Years of Age.

The association between modifiable risk factors and caries in children has been documented; however, most studies have been cross-sectional and have not considered the complexity of dietary factors and oral health habits. This study aimed to investigate the prospective association between dietary patterns and oral health behaviours at 4 years of age and the development of new decayed, missing, and filled teeth (d3-6mft/D3-6MFT) over a period of three years. Participants were children from the Generation XXI population-based birth cohort. At 4 years of age, diet patterns were assessed using a food frequency questionnaire, with three dietary patterns being identified. For the purpose of capturing the new development of caries between 4 and 7 years of age, two dental outcomes were defined in the mixed dentition: "dental caries development" and "severe dental caries development" in the mixed dentition. Bivariate analysis and multivariate logistic regression were used. From 4 to 7 years of age, 51.2% of the children had at least one new d3-6mft/D3-6MFT and 27.4% had more than two new d3-6mft/D3-6MFT. Children belonging to the "energy-dense foods" (OR = 2.19; 95% CI: 1.20-4.00) and "snacking" (OR = 2.19; 95% CI: 1.41-3.41) dietary patterns at 4 years old were associated with severe dental caries development three years later. Preventive strategies should be implemented in an attempt to reduce snacking and the consumption of energy-dense, micronutrient-poor foods to promote children's oral health.

Ultra-processed food consumption, appetitive traits and BMI in children: a prospective study.

This study aimed to investigate the association of ultra-processed food consumption at 4 and 7 years of age with appetitive traits at 7 years and BMI at 10 years of age. Participants were 1175 children of the population-based birth cohort Generation XXI, who provided food diaries and complete data on socio-demographic variables, anthropometric measures and the Portuguese Children's Eating Behaviour Questionnaire (P-CEBQ). Foods were grouped according to NOVA classification into: 'unprocessed, minimally or moderately processed, and culinary preparations'; 'processed' and 'ultra-processed'. To assess tracking of groups' consumption, Pearson's correlation coefficient (r) and the intraclass correlation coefficient (ICC) were calculated. Generalised linear models were fitted to test main associations, mediators and interactions among the variables. Ultra-processed consumption exhibited a fair level of stability between ages 4 and 7 years (r 0·34; ICC = 0·32; 95 % CI 0·25, 0·39), corresponding, respectively, to 27·3 % (1881·9 (SD 908·8) kJ/d) and 29·3 % (2204·5 (SD 961·1) kJ/d) of total energy intake. After adjusting for maternal and child characteristics, higher ultra-processed consumption at 4 years was associated directly with 'Food Responsiveness' (ß = 0·019; 95 % CI 0·007, 0·037) and indirectly through energy intake with avoidant traits: 'Food Fussiness' (ß = -0·007; 95 % CI 0·002, 0·012) and 'Satiety Responsiveness' (ß = -0·007; 95 % CI 0·003, 0·012). Ultra-processed consumption at 4 years old was associated with BMI at 10 years old, but appetitive behaviours were not powerful mediators of this association. The results suggest a path by which ultra-processed products may impact on later appetitive traits and higher BMI in children.

Bidirectional relationships between appetitive behaviours and body mass index in childhood: a cross-lagged analysis in the Generation XXI birth cohort.

PURPOSE: Appetitive behaviours have been associated with body mass index (BMI). However, existing data were largely derived from cross-sectional studies and cannot provide insight into the direction of associations. We aimed to explore the bidirectionality of these associations in school-age children. METHODS: Participants are from the Generation XXI birth cohort, assessed at both 7 and 10 years of age (n = 4264; twins excluded). The Children's Eating Behaviour Questionnaire (CEBQ) was used to measure appetitive behaviours (8 subscales). Anthropometrics were measured and WHO BMI z-score was calculated. Cross-lagged analyses were performed to compare the magnitude and direction of the associations (behaviours at 7 years to BMI z-score at 10 years and the reverse) (covariates: child's sex, physical exercise, maternal age and education; plus BMI z-score at age 7 or, in the reverse direction, the subscale score). RESULTS: In cross-lagged analyses, appetitive behaviours at 10 years of age (apart from emotional undereating) were shown to be reactive to the child BMI z-score at 7 years of age. Only slowness in eating was significantly related to subsequent BMI. However, the strongest association was from the child BMI z-score to the behaviour (ßstandardized = - 0.028 compared with ßstandardized = - 0.103, likelihood ratio test p < 0.001). CONCLUSIONS: BMI at age 7 was related to appetitive behaviours at 10 years of age, rather than the reverse. This suggests that children with a higher BMI in middle childhood are at increased risk of developing an avid appetite over time.

Physiological Stress Reactions in Red Deer Induced by Hunting Activities.

Hunting activity is usually seen as a factor capable of causing an intense stress response in wildlife that may lead to short but also long-term stress. In the Lousã Mountain, Portugal, the population of red deer (Cervus elaphus) is the target of intensive seasonal hunting. We collected and measured cortisol (and its metabolites) in three tissues types (blood, feces and hair) from red deer hunted during two hunting seasons to evaluate the stress levels at different time windows. We also assessed the immunological and physical condition of the animals. We predicted that the hunting activity would act as a stressor inducing increased short and long-term stress levels in the population. Results showed an increase in hair cortisol levels during the months of harvesting. Surprisingly, the tendency for plasma cortisol levels was to decrease during the hunting season, which could be interpreted as habituation to hunting activity, or due to the hunting duration. Contrary to our predictions, fecal cortisol metabolites did not show any clear patterns across the months. Overall, our results suggest an influence of hunting activities on the physiological stress in red deer. In addition, hair seems to be useful to measure physiological stress, although more studies are required to fully understand its suitability as an indicator of long-term stress. Methodologically, our approach highlights the importance of simultaneously using different methods to assess short and long-term effects in studies on physiological stress reactions.

The role of socio-economic factors in food consumption of Portuguese children and adolescents: results from the National Food, Nutrition and Physical Activity Survey 2015-2016.

This study aimed to evaluate the association between socio-economic factors and the food consumption of a young population. Participants were from the Portuguese National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016) aged from 3 to 17 years (n 1153). Food consumption was assessed using two non-consecutive days of food diaries in children and two 24-h recalls for adolescents. A latent class analysis (LCA) was used to classify children's socio-economic status (socio-economic composite classification (SCC)), categorised in low, middle or high. The associations between socio-economic variables and food consumption were evaluated through linear or logistic regression models, weighted for the Portuguese population distribution. A positive association was found between belonging to a higher level of SCC and consumption of fruits and vegetables (FV), by children (ß = 2·4, 95 % CI 1·1, 3·8) and by adolescents (ß = 52·4, 95 % CI 9·6, 95·3). A higher SCC, but particularly higher maternal education, was positively associated with consumption of 'white meat, fish and eggs'. Both higher SCC and parental education were positively associated with salty snack consumption in the adolescents' group. In conclusion, children and adolescents with higher educated parents and belonging to a high socio-economic level have a higher daily intake of FV and white meat, fish and eggs. Socio-economic factors play an important role in justifying differences in the food consumption of children and adolescents and must be considered in future interventions. The relationship between higher socio-economic position and salty snack consumption in adolescents needs to be further explored in other populations.

Total, added and free sugar intakes, dietary sources and determinants of consumption in Portugal: the National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016).

OBJECTIVE: To assess total sugar (TS), added sugar (AS) and free sugar (FS) intakes, dietary sources, adherence to recommendations and determinants of consumption, in a Portuguese national sample. DESIGN: Cross-sectional study. Dietary assessment was obtained by two food diaries in children aged <10 years and two non-consecutive 24 h recalls for other age groups. TS, AS and FS intakes were estimated by using SPADE software. TS content in food was estimated at the ingredient level. AS content in food was assessed through a systematic methodology and FS was based on the WHO definition. SETTING: National Food, Nutrition and Physical Activity Survey (IAN-AF 2015-2016), Portugal. PARTICIPANTS: Representative sample from the Portuguese population, aged from 3 months to 84 years (n 5811). RESULTS: Mean daily intake and contribution to total energy intake (E%) were 84·3 g/d (18·5 E%) for TS, 32·1 g/d (6·8 E%) for AS and 35·3 g/d (7·5 E%) for FS. Of the population, 76 % adhered to the FS recommendation (FS < 10 E%). The lowest adherence was in children (51·6 %) and adolescents (51·3 %). The main dietary source of TS was fruit across all ages, except in adolescents which was soft drinks. In children, the main dietary sources of FS were yoghurts and sweets, soft drinks in adolescents and table sugar in adults/elderly. FS intake was lower in children with more educated parents and in adults who practised physical activity regularly, and higher among smokers. CONCLUSIONS: Interventions ought to be planned towards decreasing intakes of added and free sugars considering population-specific characteristics.

Adherence to a healthy eating index from pre-school to school age and its associations with sociodemographic and early life factors.

Childhood is considered an important period for the development of healthy eating behaviours. This study aimed to evaluate the influence of early life factors and sociodemographic characteristics, including early diet quality, on diet quality at 7 years. The sample includes 5013 children evaluated at the ages of 4 and 7 years from the Portuguese birth cohort Generation XXI with complete information on FFQ. A healthy eating index was developed at both ages to assess adherence to the WHO's dietary recommendations, including eight food groups. Consumption quartiles were obtained for each group at 4 years and assigned a score between 1 and 4. A higher score represents a higher adherence to a better diet (range: 8 to 32). The associations between early life factors and sociodemographic characteristics and the score of the healthy eating index at 7 years were evaluated through linear regression models. The healthy eating index had an average score of 21⋅4 ± 3⋅53 (range: 12 to 32) at 4 years and 20⋅3 ± 3⋅36 (range: 11 to 31) at 7 years. After adjustment for confounders, a positive association was found between the healthy eating index at 4 and 7 years (ß = 0⋅384, 95 % CI 0⋅356, 0⋅441). Maternal years of education (ß = 0⋅094, 95 % CI 0⋅071, 0⋅116) and dietary score (ß = 0⋅182, 95 % CI 0⋅155, 0⋅209) were positively associated with increasing dietary quality from 4 to 7 years. A healthier diet at preschool age, higher maternal education and a healthier diet increase the likelihood of maintaining a high healthy eating index score at school age.

Eating frequency and weight status in Portuguese children aged 3-9 years: results from the cross-sectional National Food, Nutrition and Physical Activity Survey 2015-2016.

OBJECTIVE: To evaluate daily eating frequency (main meals and snacks) in relation to weight status in children aged 3-9 years, representative of the Portuguese population. DESIGN: Cross-sectional study. Dietary intake was estimated as the mean of two non-consecutive days of food diaries, followed by face-to-face interviews. Weight and height were measured by trained observers. Eating occasions (EO) were defined by the children's caregiver; an EO was considered separate if the time of consumption was different from other EO and it provided at least 209 kJ (50 kcal). Main meals defined as 'breakfast', 'lunch' and 'dinner' could be selected only once per day. The remaining EO were considered snacks. The association between eating frequency and overweight/obesity was evaluated through logistic regressions weighted for the population distribution. SETTING: National Food, Nutrition and Physical Activity Survey of the Portuguese population, 2015-2016. PARTICIPANTS: Portuguese children aged 3-9 years with complete dietary data and anthropometric measurements (n 517). RESULTS: Overall, the number of daily EO ranged from 3·5 to 11, and on average children had 5·7 daily EO. After adjustment for child's sex, age and total energy intake, and considering only plausible energy intake reporters, having < 3 snacks/d was positively associated with being overweight/obese (OR = 1·98; 95 % CI 1·00, 3·90), compared with having ≥ 3 snacks/d. CONCLUSIONS: Lower daily frequency of EO was associated with increased odds of being overweight or obese in children. A higher eating frequency, maintaining the same energy intake, seems to contribute to a healthy body weight in children.