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In reports among mostly, US, white, preschool and young school-age children eating in the absence of hunger (EAH) has been positively related to adiposity, with some support for a sex-specific relationship. There is considerable interest in EAH and obesity in populations at risk for obesity—like populations of countries that have undergone rapid development. We assessed adolescents (n = 679) after an overnight fast with anthropometry and an EAH paradigm beginning with an ad lib pre-load meal. Participants reported satisfaction and perceived ability to eat more food, and then proceeded to a room with freely available snacks where they were permitted to eat ad lib for 20 min. Adolescents were 16.8 years old, 52% male, and 14% with obesity. Median preload meal kcal consumption was 602 (IQR 474–746). Additional calories were consumed at the EAH snack by 47.6%. Among those who ate snack, 155 additional calories were consumed (IQR 78–283). Adolescents with obesity had 0.61 (95% CI 0.37–0.99) reduced odds of eating at the EAH snack adolescents without obesity. Adolescents with obesity were also less likely to eat above the median total calories compared to adolescents without obesity (OR = 0.59, 95% CI 0.36–0.96). A sex by obesity interaction term was not significant in any model. Obesity was related to eating behavior in our sample of Chilean adolescents, however not in the direction we hypothesized. Adolescents with obesity were less likely to eat additional calories in the EAH paradigm and ate fewer total calories compared to adolescents without obesity. [ABSTRACT FROM AUTHOR]

Summary: Background: Early life factors can programme future risk for cardiovascular disease. Objectives: We explored associations between adolescent adiponectin levels and concomitant metabolic alteration and also looked at the association between early life factors and adolescent adiponectin levels. Methods: We studied a longitudinal cohort of low‐income to middle‐income Chilean adolescents who were enroled in an infancy iron‐deficiency anaemia preventive trial and follow‐up studies at the Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile. In the 577 adolescents who were assessed as part of the 16‐year follow‐up, we evaluated independent associations between adiponectin levels and metabolic disturbances during adolescence. We also assessed the association between early life factors [short breastfeeding {<6 months} and infancy weight gain] and adolescent adiponectin levels. Results: Participants were 16.8 years old (16.4–18.1), 48% female and 38% overweight/obese. Adolescent adiponectin levels were inversely associated with metabolic disturbances: altered homeostatic model assessment of insulin resistance and high‐density lipoprotein cholesterol [odds ratios {95% confidence interval} = 0.87 {0.79–0.95}, p‐value = 0.002, and 0.90 {0.87–0.94}, p‐value < 0.001, respectively], adjusting for sex and fat mass index. Early life factors were independently associated with adolescent adiponectin levels, which decreased 0.88 ug mL−1 per each unit increase in weight‐for‐age z‐score between 0 and 6 months and was 1.58 ug mL−1 lower among participants with short breastfeeding. Conclusions: Higher adolescent adiponectin levels were independently associated with lower odds of metabolic disturbances. Greater weight gain during infancy and shorter breastfeeding were associated with lower adolescent adiponectin levels, supporting research indicating early life as a window of opportunity for prevention of later cardiovascular alterations. © 2017 World Obesity Federation [ABSTRACT FROM AUTHOR]

Background Increased cardiometabolic risk ( CMR) is documented in obese and non-obese adolescents with low muscular fitness. However, the association of low muscle mass ( LMM) with CMR, independent of weight status, has not been examined. We analyzed the relationship of LMM with CMR in adolescents, regardless of their weight status. Materials and Methods Observational study in 660 adolescents. BMI, waist circumference ( WC), arterial blood pressures ( ABP) were measured. Total fat mass ( TFM), total lean tissue ( TLT), and appendicular skeletal muscle mass ( ASM) were estimated ( DXA). Fasting lipid profile, glucose, and insulin were measured. HOMA-IR was estimated. Metabolic Syndrome ( MetS) was diagnosed ( AHA/ NHLBI/ IDF). ROC analysis was performed to find the optimal cutoffs of TLT percentage for MetS diagnosis. Values below these cutoffs defined LMM. ANCOVA examined the association of LMM with selected cardiometabolic biomarkers. Results In both sexes, TLT showed better sensitivity and specificity than ASM for MetS diagnosis. In males and females, TLT of 66.1% and 56.3%, respectively, were the optimal cutoff for MetS diagnosis. In the sample, 17.3% of males and 23.7% of females had LMM. In both sexes, adolescents with LMM had significantly higher values of WC, ABP, TG, TC/ HDL, HOMA-IR, and MetS z-score than non- LMM participants. Adolescents with LMM, regardless nutritional status, had significantly increased values of MetS z-score, ABP, TG, TC/ HDL-chol, and HOMA-IR than non-obese non- LMM adolescents. Adolescents having both obesity and LMM had the unhealthiest CMR profile. Conclusion In adolescents, LMM was associated with higher CMR, regardless of nutritional status. In obese adolescents, LMM increased obesity-associated CMR. [ABSTRACT FROM AUTHOR]

Summary: Little is known regarding the relationship between early life factors and bone mineral density (BMD). We found a positive association between breastfeeding for at least 6 months, without formula supplementation, and whole body adolescent BMD z-score. Introduction: The aim of the study is to assess the role of breastfeeding BF on adolescent bone mineral density (BMD) in a cohort prospectively followed since infancy. Methods: We studied 679 participants from an infancy iron deficiency anemia preventive trial in Santiago, Chile, followed to adolescence. Breast and bottle feeding were ascertained weekly from 4 to 12 months. At 16 years, whole body BMD was assessed by DEXA. Using linear regression, we evaluated associations between BF duration and BF as the sole source of milk and adolescent BMD z-score, adjusting for possible infancy, adolescent, and background confounders. Results: Mean birth weight and length were 3.5 (0.3) kg and 50.7 (1.6) cm. For at least 6 months, BF was the sole source of milk for 26.3% and with supplementation for 36.7%. For 37%, BF was provided for less than 6 months. Mean 16-year BMD z-score was 0.25 (1.0). Covariates included male sex, birth length, and gestational age. BF as the sole source of milk ≥6 months, compared to BF < 6 months, was associated with higher adolescent BMD z-score adjusting for covariates ( β = 0.29, p < 0.05). Mixed BF was not significantly related to adolescent BMD z-score ( β = 0.06, p = 0.47). For every 30 days of BF as the sole source of milk, adolescent BMD z-score increased by 0.03 ( p = 0.01). Conclusion: BF without formula supplementation for at least 6 months was associated with higher adolescent BMD z-score and a suggestive trend in the same direction for BMD suggests that exclusivity and duration of BF may play a role in adolescent bone health. [ABSTRACT FROM AUTHOR]

This paper estimates the agricultural production water footprint (WF) of Chile, assessing green, blue and grey WFs of the main agricultural products for the main productive regions, taking into account climatic and soil differences. Chile's agricultural production blue WF is geographically concentrated in the lower portion of the Northern Dry Pacific and Central Chile area, which present less water availability. Thus, irrigated agricultural production in Chile, a semiarid country, is characterized by high water stress. In this scenario, public policies are required to incentivize better water management in order to reduce water vulnerability while boosting development. [ABSTRACT FROM AUTHOR]

Background Poor motor skills have been consistently linked with a higher body weight in childhood, but the causal direction of this association is not fully understood. This study investigated the temporal ordering between children's motor skills and weight status at 5 and 10 years. Methods Participants were 668 children (54% male) who were studied from infancy as part of an iron deficiency anaemia preventive trial and follow-up study in Santiago, Chile. All were healthy, full-term and weighing 3 kg or more at birth. Cross-lagged panel modelling was conducted to understand the temporal precedence between children's weight status and motor proficiency. Analyses also examined differences in gross and fine motor skills among healthy weight, overweight, and obese children. Results A higher BMI at 5 years contributed to declines in motor proficiency from 5 to 10 years. There was no support for the reverse, that is, poor motor skills at 5 years did not predict increases in relative weight from 5 to 10 years. Obesity at 5 years also predicted declines in motor proficiency. When compared with normal weight children, obese children had significantly poorer total and gross motor skills at both 5 and 10 years. Overweight children had poorer total and gross motor skills at 10 years only. The differences in total and gross motor skills among normal weight, overweight and obese children appear to increase with age. There were small differences in fine motor skill between obese and non-obese children at 5 years only. Conclusions Obesity preceded declines in motor skills and not the reverse. Study findings suggest that early childhood obesity intervention efforts might help prevent declines in motor proficiency that, in turn, may positively impact children's physical activity and overall fitness levels. [ABSTRACT FROM AUTHOR]

Objective. This study examined how family environmental characteristics served as mediators in the relationship between socioeconomic conditions and infant growth in a cohort of Chilean infants. Methods. We studied 999 infants, born between 1991 and 1996, from a longitudinal cohort which began as an iron deficiency anemia preventive trial. SES (Graffar Index), the Life Experiences Survey, and the Home Observation for Measurement of the Environment (HOME) were assessed in infancy. Using path analysis, we assessed the relationships between the social factors, home environment, and infant growth. Results. During the first year, weight and length gain averaged 540 grams/month and 6.5 cm/month, respectively. In the path analysis model for weight gain, higher SES and a better physical environment were positively related to higher maternal warmth, which in turn was associated with higher average weight gain. Higher SES was directly related to higher average length gain. Conclusions. In our cohort, a direct relationship between SES and length gain developed during infancy. Higher SES was indirectly related to infant weight gain through the home environment and maternal warmth. As the fastest growing infants are at risk for later obesity, new strategies are needed to encourage optimal rather than maximal growth. [ABSTRACT FROM AUTHOR]

Summary: Background: While the genetic contribution to obesity is well established, few studies have examined how genetic variants influence standardized body mass index Z‐score (BMIz) in Hispanics/Latinos, especially across childhood and adolescence. Objectives: We estimated the effect of established BMIz loci in Chilean children of the Santiago Longitudinal Study (SLS). Methods: We examined associations with BMIz at age 10 for 15 loci previously identified in European children. For significant loci, we performed association analyses at ages 5 and 16 years, for which we have smaller sample sizes. We tested associations of unweighted genetic risk scores (GRSs) for previously identified tag variants (GRS_EUR) and from the most significant variants in SLS at each locus (GRS_SLS). Results: We generalized five variants at age 10 (P < 0.05 and directionally consistent), including rs543874 that reached Bonferroni‐corrected significance. The effect on BMIz was greatest at age 10 for all significant loci, except FTO, which exhibited an increase in effect from ages 5 to 16. Both GRSs were associated with BMIz (P < 0.0001), but GRS_SLS explained a much greater proportion of the variation (13.63%). Conclusion: Our results underscore the importance of conducting genetic investigations across life stages and selecting ancestry appropriate tag variants in future studies for disease prediction and clinical evaluation. [ABSTRACT FROM AUTHOR]

LED spectrophotometry is a robust technique for the indirect characterization of wastewater pollutant load through correlation modeling. To tackle this issue, a dataset with 1300 samples was collected, from both raw and treated wastewater from 45 wastewater treatment plants in Spain and Chile collected over 4 years. The type of regressor, scaling, and dimensionality reduction technique and nature of the data play crucial roles in the performance of the processing pipeline. Eighty-four pipelines were tested through exhaustive experimentation resulting from the combination of 7 regression techniques, 3 scaling methods, and 4 possible dimensional reductions. Those combinations were tested on the prediction of chemical oxygen demand (COD) and total suspended solids (TSS). Each pipeline underwent a tenfold cross-validation on 15 sub-datasets derived from the original dataset, accounting for variations in plants and wastewater types. The results point to the normalization of the data followed by a conversion through the PCA to finally apply a Random Forest Regressor as the combination which stood out These results highlight the importance of modeling strategies in wastewater management using techniques such as LED spectrophotometry., (© 2024. The Author(s).)

Biomass burning is common in much of the world, and in some areas, residential wood-burning has increased. However, air pollution resulting from biomass burning is an important public health problem. A sampling campaign was carried out between May 2017 and July 2018 in over 64 sites in four sessions, to develop a spatio-temporal land use regression (LUR) model for fine particulate matter (PM) and wood-burning tracers levoglucosan and soluble potassium (K sol ) in a city heavily impacted by wood-burning. The mean (sd) was 46.5 (37.4) μg m -3 for PM 2.5 , 0.607 (0.538) μg m -3 for levoglucosan, and 0.635 (0.489) μg m -3 for K sol . LUR models for PM 2.5 , levoglucosan, and K sol had a satisfactory performance (LOSOCV R 2 ), explaining 88.8%, 87.4%, and 87.3% of the total variance, respectively. All models included sociodemographic predictors consistent with the pattern of use of wood-burning in homes. The models were applied to predict concentrations surfaces and to estimate exposures for an epidemiological study.

Background: Optimizing cognitive development through early adulthood has implications for population health. This study aims to understand how socioeconomic position (SEP) across development relates to executive functioning. We evaluate three frameworks in life-course epidemiology - the sensitive period, accumulation, and social mobility hypotheses., Methods: Participants were young adults from Santiago, Chile who were studied from 6 months to 21 years. Family SEP was measured at ages 1 y, 10 y, and 16 y with the modified Graffar Index. Executive functioning was assessed at ages 16 y and 21 y by the Trail Making Test Part B (Trails B). Analyses estimating 16 y and 21 y executive function involved 581 and 469 participants, respectively. Trails B scores were modeled as a function of SEP at 1 y, 10 y, and 16 y, as the total accumulation of disadvantage, and as change in SEP between 1 y and 10 y and between 10 y and 16 y., Results: Participants were low- to middle-income in infancy and, on average, experienced upwards mobility across childhood. Half of participants (58%) improved Trails B scores from 16 y and 21 y. Most (68%) experienced upward social mobility between infancy and 16 y. When examined independently, worse SEP measured at 10 y and 16 y related to worse (longer time to complete) Trails B scores at Age 21 but did not relate to the other outcomes. After mutual adjustment as a test of the sensitivity hypothesis, no SEP measure was independently related to any outcome. Testing the accumulation hypothesis, cumulative low SEP was associated with worse cognitive performance at 21 y (β = 3.6, p = 0.04). Results for the social mobility hypothesis showed no relation to cognitive scores or to change in cognitive scores. Comparing all hypotheses, SEP at 16 y explained the most variability in executive functioning at 21 y, providing support for the sensitive period hypothesis., Conclusions: Results indicate that experiencing cumulatively low socioeconomic position from infancy to adolescence can have a negative impact on cognitive functioning in young adulthood. Findings also provide evidence in support of adolescence as a key developmental period during which SEP can most strongly impact cognitive functioning., Competing Interests: Declaration of Competing Interest No author reports any conflict of interest associated with this publication. We have not received any financial support for this work that could have influenced its outcome., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Understanding temporal and spatial trends in pregnancy and birth outcomes within an urban area is important for the monitoring of health indicators of a population. We conducted a retrospective cohort study of all births in the public hospital of Temuco, a medium-sized city in Southern Chile between 2009 and 2016 (n = 17,237). Information on adverse pregnancy and birth outcomes, as well as spatial and maternal characteristics (insurance type, employment, smoking, age, and overweight/obesity), was collected from medical charts. Home addresses were geocoded and assigned to neighborhood. We tested whether births and prevalence of adverse pregnancy outcomes changed over time, whether birth events were spatially clustered (Moran's I statistic), and whether neighborhood deprivation was correlated to outcomes (Spearman's rho). We observed decreases in eclampsia, hypertensive disorders of pregnancy, and small for gestational age, while gestational diabetes, preterm birth, and low birth weight increased over the study period (all p < 0.01 for trend), with little changes after adjusting for maternal characteristics. We observed neighborhood clusters for birth rate, preterm birth, and low birth weight. Neighborhood deprivation was negatively correlated with low birth weight and preterm birth, but not correlated with eclampsia, preeclampsia, hypertensive disorders of pregnancy, small for gestational age, gestational diabetes, nor stillbirth. Several encouraging downward trends and some increases in adverse pregnancy and birth outcomes, which, overall, were not explained by changes in maternal characteristics were observed. Identified clusters of higher adverse birth outcomes may be used to evaluate preventive health coverage in this setting., (© 2023. The New York Academy of Medicine.)

Growth in early infancy is hypothesized to affect chronic disease risk factors later in life. To date, most reports draw on European-ancestry cohorts with few repeated observations in early infancy. We investigated the association between infant growth before 6 months and lipid levels in adolescents in a Hispanic/Latino cohort. We characterized infant growth from birth to 5 months in male (n = 311) and female (n = 285) infants from the Santiago Longitudinal Study (1991-1996) using 3 metrics: weight (kg), length (cm), and weight-for-length (g/cm). Superimposition by translation and rotation (SITAR) and latent growth mixture models (LGMMs) were used to estimate the association between infant growth characteristics and lipid levels at age 17 years. We found a positive relationship between the SITAR length velocity parameter before 6 months of age and high-density lipoprotein cholesterol levels in adolescence (11.5, 95% confidence interval; 3.4, 19.5), indicating higher high-density lipoprotein cholesterol levels occurring with faster length growth. The strongest associations from the LGMMs were between higher low-density lipoprotein cholesterol and slower weight-for-length growth, following a pattern of associations between slower growth and adverse lipid profiles. Further research in this window of time can confirm the association between early infant growth as an exposure and adolescent cardiovascular disease risk factors., (© The Author(s) 2022. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Orexin-A, a hormone secreted by orexin neurons, is involved in caloric-intake regulation. Current understanding is based primarily on animal studies. Studies of orexin in humans are scarce, and to our knowledge there are no prior studies in adolescents. We studied fasting Orexin-A levels related to energy intake at breakfast and a subsequent snack in adolescents (n = 668) from a longitudinal study in Chile. Body-Mass Index (BMI), components of the metabolic syndrome and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured. Energy intake was calculated based on food weights before and after the standardized breakfast and subsequent snack. High energy intake was defined as ≥ 75th percentile. We assessed the relationship between orexin-A and high energy intake, adjusting for confounders. Higher orexin levels were associated with high breakfast energy intake (OR: 1.21; 95%CI: 0.98-1.49). Conversely, those with higher orexin levels showed a non-significant trend for lower odds of high energy intake for the snack (OR: 0.87; 95%CI: 0.70-1.07). There was a significant interaction between high breakfast energy intake and orexin levels. Those who ate more calories at breakfast displayed a lower inhibitory effect of orexin on eating at the snack (p < 0.05). There was no significant interaction between weight status and orexin. In conclusion, orexin-A levels were associated with breakfast energy intake and inversely related with subsequent snack energy intake in participants whose caloric intake at breakfast was within the normal range. Based on these findings, it appears that the association of orexin-A with energy intake depends on eating behavior., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Orexin-A, a hormone secreted by orexin neurons, is involved in caloric-intake regulation. Current understanding is based primarily on animal studies. Studies of orexin in humans are scarce, and to our knowledge there are no prior studies in adolescents. We studied fasting Orexin-A levels related to energy intake at breakfast and a subsequent snack in adolescents (n = 668) from a longitudinal study in Chile. Body-Mass Index (BMI), components of the metabolic syndrome and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured. Energy intake was calculated based on food weights before and after the standardized breakfast and subsequent snack. High energy intake was defined as ≥ 75th percentile. We assessed the relationship between orexin-A and high energy intake, adjusting for confounders. Higher orexin levels were associated with high breakfast energy intake (OR: 1.21; 95%CI: 0.98-1.49). Conversely, those with higher orexin levels showed a non-significant trend for lower odds of high energy intake for the snack (OR: 0.87; 95%CI: 0.70-1.07). There was a significant interaction between high breakfast energy intake and orexin levels. Those who ate more calories at breakfast displayed a lower inhibitory effect of orexin on eating at the snack (p < 0.05). There was no significant interaction between weight status and orexin. In conclusion, orexin-A levels were associated with breakfast energy intake and inversely related with subsequent snack energy intake in participants whose caloric intake at breakfast was within the normal range. Based on these findings, it appears that the association of orexin-A with energy intake depends on eating behavior., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Background: Appetite regulation is integral to food intake and is modulated by complex interactions between internal and external stimuli. Hormonal mechanisms which stimulate or inhibit intake have been characterized, but the physiologic effects of serum levels of such hormones in short-term appetite regulation have received little attention., Aim: To evaluate whether fasting levels of orexigenic/anorexigenic hormones were associated with energy intake at breakfast, served soon after drawing a fasting blood sample, in a group of adolescents., Material and Methods: Anthropometry, body composition and fasting blood levels of leptin, insulin, ghrelin, and orexin-A were measured in 655 Chilean adolescents aged 16.8 ± 0.3 years (52% males). Energy intake was measured at a semi-standardized breakfast. Associations between hormone levels and energy intake were studied using multivariate linear models., Results: Thirty nine percent of participants were overweight/ obese. After an overnight fast, median values for leptin, insulin, ghrelin and orexin-A were 7.3 ng/mL, 6.7 IU/dL, 200.8 pg/mL, and 16.1 pg/mL, respectively. Participants ate on average 637 ± 239 calories at breakfast. In multivariable models, insulin levels were inversely and independently associated with caloric intake at breakfast (β = -18.65; p < 0.05), whereas leptin, ghrelin and orexin-A levels were positively and independently associated with intake: β= 5.56, β = 0.34 and β = 8.40, respectively, p < 0.05., Conclusions: Fasting leptin, ghrelin and orexin-A were positively associated with energy intake during breakfast provided soon after the blood draw. Insulin was negatively associated with energy intake. Modifiable factors influencing levels of appetite regulating hormones could be a potential target for influencing food intake.

Background: The genetic underpinnings of glycemic traits have been understudied in adolescent and Hispanic/Latino (H/L) populations in comparison to adults and populations of European ancestry., Objective: To identify genetic factors underlying glycemic traits in an adolescent H/L population., Methods: We conducted a genome-wide association study (GWAS) of fasting glucose (FG) and fasting insulin (FI) in H/L adolescents from the Santiago Longitudinal Study., Results: We identified one novel variant positioned in the CSMD1 gene on chromosome 8 (rs77465890, effect allele frequency = 0.10) that was associated with FI (β = -0.299, SE = 0.054, p = 2.72×10 -8 ) and was only slightly attenuated after adjusting for body mass index z-scores (β = -0.252, SE = 0.047, p = 1.03×10 -7 ). We demonstrated directionally consistent, but not statistically significant results in African and Hispanic adults of the Population Architecture Using Genomics and Epidemiology Consortium. We also identified secondary signals for two FG loci after conditioning on known variants, which demonstrate allelic heterogeneity in well-known glucose loci., Conclusion: Our results exemplify the importance of including populations with diverse ancestral origin and adolescent participants in GWAS of glycemic traits to uncover novel risk loci and expand our understanding of disease aetiology., (© 2020 World Obesity Federation.)

Aim: We investigated the relation of time of onset and length of obesity with biomarkers of β-cell function in early adulthood in an infancy cohort., Material and Methods: In 1039 23-year-olds, body-mass index (BMI) was measured at multiple time-points from enrollment. BMI trajectories were interpolated with cubic polynomials. Fasting glucose, insulin and adiponectin were measured at 23 years. Homeostatic model assessment-insulin resistance (HOMA-IR), HOMA-S, HOMA-β, HOMA-adiponectin (AD) and disposition index (DI) were estimated. IR and non-alcoholic fatty liver (NAFL) were diagnosed. According to the BMI trajectory, five groups were defined: participants who were never obese (NOB); participants with obesity starting in adolescence and remained obese into adulthood (recent-onset obesity, ROB); participants who were obese in early childhood but transitioned to non-obesity as preadolescents (former obesity, FOB); participants who were obese in early childhood and remained obese into adulthood (persistent obesity, POB); participants with obesity starting in preadolescence and transitioned to non-obesity as adolescents (transient obesity; TOB)., Results: Obesity was present in 47% of participants during at least one time-point. ROBs and POBs had higher insulin, HOMA-IR and HOMA-β, lower HOMA-S and DI, and higher prevalence of IR and NAFL at 23 years than NOBs, TOBs and FOBs. No differences were found in the β-cell functionality of NOBs, TOBs and FOBs., Conclusions: Persistent and recent obesity are both related to IR, NAFL and a decline of β-cell function in emerging adulthood. Defeating obesity in childhood or adolescence allows reaching emerging adulthood with β-cell functioning similar to that of subjects who were NOB., (© 2020 John Wiley & Sons Ltd.)

Background: Notable weight gain is observed during young adulthood, compared to other adult age groups, yet the relation between eating behavior and body composition at this stage remains poorly understood., Objective: The aim of this cross-sectional study was to assess the association between eating behavior scores (cognitive restraint, uncontrolled eating, and emotional eating), and body composition in a sample of Chilean young adults., Methods: Logistic and linear regression models assessed the independent associations between cognitive restraint, uncontrolled eating, and emotional eating, derived from the Three Factor Eating Questionnaire-R18, and body mass index (BMI), percent body fat by dual-energy X-ray absorptiometry, and central obesity, accounting for demographic covariates, stratified by sex, in a sample of 555 participants of the Santiago Longitudinal Study (mean age 22.6 years [SD 0.4])., Results: Cognitive restraint was positively associated with obesity, defined by BMI, % body fat, and central obesity. Emotional eating was related to obesity, defined by % body fat and central obesity in men and women and to obesity, defined by BMI, in women. Cognitive restraint was related to BMI in men and % body fat in women. Uncontrolled eating was not associated with adiposity in men or women., Conclusions: In Chilean young adults, cognitive restraint and emotional eating scores were associated with higher BMI, elevated percent body fat, and greater central obesity., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Greater psychosocial risk in childhood and adolescence predicts poorer cardiometabolic outcomes in adulthood. We assessed whether the timing of psychosocial risk from infancy through adolescence predicts cardiometabolic outcomes in young adulthood. Young adults and their mothers participated in a longitudinal study beginning in infancy in Santiago, Chile (N = 1040). At infancy, 5 years, 10 years, and adolescence, mothers reported on depressive symptoms, stressful experiences, support for child development in the home, father absence, parental education, and socioeconomic status (SES) to create a psychosocial risk composite at each time point. Young adults (52.1% female; 21-27 years) provided fasting serum samples and participated in anthropometric and blood pressure (BP) assessments, including a dual-energy X-ray absorptiometry (DXA) scan for measuring body fat. Greater infant psychosocial risk was associated with a greater young adult metabolic syndrome score (β = 0.07, 95% confidence intervals (CI): 0.01 to 0.13, p = 0.02), a higher body mass index and waist circumference composite (β = 0.08, 95% CI: 0.03 to 0.13, p = 0.002), and a higher body fat (DXA) composite (β = 0.07, 95% CI: 0.01 to 0.12, p = 0.02). No psychosocial risk measure from any time point was associated with BP. Infant psychosocial risk predicted cardiometabolic outcomes in young adulthood better than psychosocial risk at 5 years, 10 years, or adolescence, mean of psychosocial risk from infancy through adolescence, and maximum of psychosocial risk at any one time. Consistent with the Developmental Origins of Health and Disease model, findings suggest that infancy is a sensitive period for psychosocial risk leading to poorer cardiometabolic outcomes in young adulthood.

Insulin measurements are not advised for cardiometabolic risk screening in large groups. Here we assessed the accuracy of the single-point insulin sensitivity estimator (SPISE) to diagnose cardiometabolic risk in Chilean adolescents. In 678 post-pubertal adolescents (52% males, M(SD) age = 16.8 (0.2) years), height, weight, waist circumference, blood lipids, glucose, insulin, and blood pressure were measured. BMI, HOMA-IR, and SPISE were estimated; HOMA-IR values ≥ 2.6 were considered insulin resistance (IR). Metabolic syndrome (MetS) was defined with the joint IDF/AHA/NHBLI standard. Using receiver operating characteristic curves, we obtained optimal SPISE cutpoints for IR and MetS diagnosis. The prevalence of MetS and IR was 8.2% and 17.1%, respectively. In males, the optimal cutoff for MetS diagnosis was 5.0 (sensitivity: 97%; specificity: 82%), and the optimal cutoff for IR diagnosis was 5.9 (sensitivity: 71%; specificity: 83%). In females, a SPISE of 6.0 had the highest sensitivity (90%) and specificity (74%) for MetS diagnosis. A SPISE of 6.4 was the optimal cutoff for IR diagnosis; however, sensitivity and specificity were 61% and 75%. In males and female post-pubertal adolescents, SPISE had a very good and good diagnostic performance, respectively, in predicting MetS. It was an accurate diagnostic tool for IR prediction in males, but not necessarily in females.

We examined the associations between adolescent risk behaviors and household chaos, and whether associations varied by adolescents' sense of school belonging. We collected data from 801 Chilean adolescents from working-class families (M age 16.2 years). Approximately, one-quarter of participants reported past-month cigarette use, and 8% and 9% reported past-month binge drinking and marijuana use, respectively. More than half of youth reported having sex (52%), 23% of youth reported having unprotected sex at their last encounter, and 14% reported having multiple sex partners. Within the past year, 16%, 36%, and 23% reported carrying a weapon, physically attacking someone, and threatening to physically hurt someone, respectively. Greater household chaos was related to increased odds of each risk behavior except unprotected sex. These associations did not vary significantly by level of school belonging. Results are compared to previously reported results using a U.S., largely Latinx sample in attempts to replicate findings across culture and context.

Introduction: This study examined changes in substance use from adolescence to young adulthood as related to adolescents' risk taking, sensation seeking, antisocial activities, and personality traits., Methods: Chilean youth (N = 890, 52% female) were studied in adolescence (14.5 and 16.2 years) and young adulthood (M age 21.3 years). Risk taking was assessed via a laboratory-based performance task (Balloon Analogue Risk Task), and self-administered questionnaires assessed sensation seeking, antisocial behaviors, personality and substance use., Results: Frequent involvement in sensation seeking and antisocial activities were associated with increased odds of continued marijuana use from adolescence to young adulthood and of illicit substance use at young adulthood. High risk taking was associated with a reduced likelihood of discontinuing marijuana use at young adulthood, and high agreeableness and conscientiousness were associated with reduced likelihood of new onset marijuana use and illicit substance use at young adulthood., Conclusions: Results highlight specific risk-taking tendencies and personality characteristics that relate to initiating, continuing, or discontinuing substance use at entry into adulthood. Sensation seeking and involvement in antisocial activities were the two foremost risk factors for continued use, which is a forecaster of drug dependence. Findings suggest potential prevention and intervention targets for abstaining from or discontinuing substance use as youth transition to adulthood., (Copyright © 2020 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.)

Objectives: Infant anthropometric growth varies across socioeconomic factors, including maternal education and income, and may serve as an indicator of environmental influences in early life with long-term health consequences. Previous research has identified sociodemographic gradients in growth with a focus on the first year and beyond, but estimates are sparse for growth before 6 months. Thus, our objective was to examine the relationship between sociodemographic factors and infant growth patterns between birth and 5 months of age., Design: Prospective cohort study., Settings: Low-income to middle-income neighbourhoods in Santiago, Chile (1991-1996)., Participants: 1412 participants from a randomised iron-deficiency anaemia preventive trial in healthy infants., Main Outcome Measures: Longitudinal anthropometrics including monthly weight (kg), length (cm) and weight-for-length (WFL) values. For each measure, we estimated three individual-level growth parameters (size, timing and velocity) from SuperImposition by Translation and Rotation models. Size and timing changes represent vertical and horizontal growth curve shifts, respectively, and velocity change represents growth rate shifts. We estimated the linear association between growth parameters and gestational age, maternal age, education and socioeconomic position (SEP)., Results: Lower SEP was associated with a slower linear (length) velocity growth parameter (-0.22, 95% CI -0.31 to -0.13)-outcome units are per cent change in velocity from the average growth curve. Lower SEP was associated with later WFL growth timing as demonstrated through the tempo growth parameter for females (0.25, 95% CI 0.05 to 0.42)-outcome units are shifts in days from the average growth curve. We found no evidence of associations between SEP and the weight size, timing or velocity growth rate parameters., Conclusion: Previous research on growth in older infants and children shows associations between lower SEP with slower length velocity. We found evidence supporting this association in the first 5 months of life, which may inform age-specific prevention efforts aimed at infant length growth., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Early adversity, depression, and obesity are associated with increases in low-grade inflammation. However, there are few prospective and longitudinal studies to elucidate how these associations unfold in children. The present study used latent growth curve models to examine pathways between family adversity in infancy, depressive symptoms in childhood, body mass index (BMI) in childhood, and inflammation in adolescence (age = 16-18). The study is an adolescent follow-up of infants from working-class communities around Santiago, Chile, who participated in a preventive trial of iron supplementation at 6 months of age. Anthropometrics, stressful life events, maternal depression, socioeconomic status, and developmental assessments were measured at 12 months, 5 years, 10 years, and adolescence. In adolescence, participants provided blood samples for high-sensitivity C-reactive protein (hsCRP) assessment. Greater exposure to early adversity in the form of interpersonal conflict stress in infancy indirectly associated with increased hsCRP through its association to increased intercept and slope of childhood BMI. Depressive symptoms at any time were not directly or indirectly associated with increased hsCRP. These findings contribute to our understanding of how early family adversity and its associations with obesity and depressive symptoms across childhood are linked to low-grade, chronic inflammation in adolescence. The model identified as best capturing the data supported the pivotal role of childhood BMI in explaining how early-life adversity is associated with inflammation in adolescence., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Aim: To explore the association of selected cardiometabolic biomarkers and metabolic syndrome (MetS) with educational outcomes in adolescents from Chile., Methods: Of 678 participants, 632 (52% males) met criteria for the study. At 16 years, waist circumference (WC), systolic blood pressure, triglycerides (TG), high-density lipoprotein and glucose were measured. A continuous cardiometabolic risk score (zMetS) using indicators of obesity, lipids, glucose and blood pressure was computed, with lower values denoting a healthier cardiometabolic profile. MetS was diagnosed with the International Diabetes Federation/American Heart Association/National Heart, Lung, and Blood Institute joint criteria. Data on high school (HS) graduation, grade point average (GPA), college examination rates and college test scores were collected. Data were analysed controlling for sociodemographic, lifestyle and educational confounders., Result: zMetS, WC, TG and homeostatic model assessment of insulin resistance at 16 years were negatively and significantly associated with the odds of completing HS and taking college exams. Notably, for a one-unit increase in zMetS, we found 52% (OR: 0.48, 95% CI 0.227 to 0.98) and 39% (OR: 0.61, 95% CI 0.28 to 0.93) reduction in the odds of HS completion and taking college exams, respectively. The odds of HS completion and taking college exams in participants with MetS were 37% (95% CI 0.14 to 0.98) and 33% (95% CI 0.15 to 0.79) that of participants with no cardiometabolic risk factors. Compared with adolescents with no risk factors, those with MetS had lower GPA (515 vs 461 points; p=0.002; Cohen's d =0.55). Adolescents having the MetS had significantly lower odds of passing the mathematics exam for college compared with peers with no cardiometabolic risk factors (OR: 0.49; 95% CI 0.16 to 0.95)., Conclusion: In Chilean adolescents, cardiometabolic health was associated with educational outcomes., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

This study examined the associations among maternal depression, mothers' emotional and material investment in their child, and children's cognitive functioning. Middle-class Chilean mothers and children (N = 875; 52% males) were studied when children were 1, 5, 10, and 16 years (1991-2007). Results indicated that highly depressed mothers provided less emotional and material support to their child across all ages, which related to children's lower IQ. Children with lower mental abilities at age 1 received less learning-material support at age 5, which led to mothers' higher depression at child age 10. Mothers' low support was more strongly linked to maternal depression as children got older. Findings elucidate the dynamic and enduring effects of depression on mothers' parenting and children's development., (© 2018 Society for Research in Child Development.)

Background: Infants who are iron-deficient anemic seek and receive less stimulation from their caregivers, predisposing such children to be functionally isolated., Objectives: To test the sequence whereby iron deficiency in infancy contributes to children's disengagement from the environment, which reduces parent stimulation which, in turn, contributes to children's poor verbal skills., Methods: Chilean children (N = 875, 54% male) were studied, 45% of whom were iron deficient or iron-deficient anemic in infancy. We used structural equation modeling to test the sequence outlined above and to examine the effect of infant iron status on children's verbal performance at ages 5 and 10 years including the roles of child and parent intermediate variables., Results: Severity of iron deficiency in infancy was associated with higher levels of children's dull affect and social reticence at 5 years (β = .10, B = .26, SE = .12, p < .05), and these behaviors were associated with parent unresponsiveness (β = .29, B = .13, SE = .03, p < .001), which related to children's lower verbal abilities at age 5 (β = - .29, B = - 2.33, SE = .47, p < .001) and age 10 (β = - .22, B = - 3.04, SE = .75, p < .001). An alternate model where poor iron status related directly to children's verbal ability was tested but not supported., Conclusions: Findings support functional isolation processes resulting from a nutritional deficiency, with iron-deficient anemic infants showing affective and behavioral tendencies that limit developmentally stimulating caregiving which, in turn, hinder children's verbal abilities.

Objectives: To test differences in cognitive outcomes among adolescents randomly assigned previously as infants to iron-fortified formula or low-iron formula as part of an iron deficiency anemia prevention trial., Study Design: Infants were recruited from community clinics in low- to middle-income neighborhoods in Santiago, Chile. Entrance criteria included term, singleton infants; birth weight of ≥3.0 kg; and no major congenital anomalies, perinatal complications, phototherapy, hospitalization >5 days, chronic illness, or iron deficiency anemia at 6 months. Six-month-old infants were randomized to iron-fortified (12 mg/L) or low-iron (2.3 mg/L) formula for 6 months. At 16 years of age, cognitive ability, visual perceptual ability, visual memory, and achievement in math, vocabulary, and comprehension were assessed, using standardized measures. We compared differences in developmental test scores according to randomization group., Results: At the follow-up assessment, the 405 participants averaged 16.2 years of age and 46% were male. Those randomized to iron-fortified formula had lower scores than those randomized to low-iron formula for visual memory, arithmetic achievement, and reading comprehension achievement. For visual motor integration, there was an interaction with baseline infancy hemoglobin, such that the iron-fortified group outperformed the low-iron group when 6-month hemoglobin was low and underperformed when 6-month hemoglobin was high., Conclusions: Adolescents who received iron-fortified formula as infants from 6 to 12 months of age at levels recommended in the US had poorer cognitive outcomes compared with those who received a low-iron formula. The prevention of iron deficiency anemia in infancy is important for brain development. However, the optimal level of iron supplementation in infancy is unclear., Trial Registration: Clinicaltrials.gov: NCT01166451., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Objective: To prospectively assess whether the infant psychosocial environment was associated with cardiometabolic risk as early as adolescence., Study Design: Participants were recruited in Santiago, Chile, and have been followed from infancy. Inclusion criteria included healthy infants with birth weight ≥3 kg and a stable caregiver. The psychosocial environment, including depressive symptoms, stressful life events, poor support for child development, father absence, and socioeconomic status, was reported by mothers at 6-12 months. Body mass index (BMI) z score was assessed at 5 and 10 years. BMI z score, waist-to-hip ratio, systolic and diastolic blood pressure, fat mass and body fat percentage, fasting glucose, total and high-density lipoprotein cholesterol, and homeostatic model of insulin resistance were tested in adolescence., Results: Adolescents ranged from 16 to 18 years of age (n = 588; 48.1% female). A poorer infant psychosocial environment was associated with BMI z score at 10 years (β = 0.10, 95% CI = 0.00-0.19) and in adolescence (β = 0.15, 95% CI = 0.06-0.24) but not at 5 years. A poorer infant psychosocial environment was associated with higher blood pressure (β = 0.15, 95% CI = 0.05-0.24), greater anthropometric risk (β = 0.13, 95% CI = 0.03-0.22), greater biomarker (triglycerides, homeostatic model assessment of insulin resistance, total cholesterol) risk (β = 0.12, 95% CI = 0.02-0.22), and a higher likelihood of metabolic syndrome in adolescence (aOR = 1.50; 95% CI = 1.06-2.12)., Conclusions: These findings demonstrate that a poorer infant psychosocial environment was associated with greater adolescent cardiometabolic risk. The results support screening for infants' psychosocial environments and further research into causality, mechanisms, prevention, and intervention., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: Early-life conditions are important for the development of obesity. We hypothesized that home and family characteristics reflective of less supportive environments during childhood will be associated with higher adult BMI and faster BMI growth between ages 5 and 21 years. We also examined the timing and acceleration of BMI increase by adult weight status (normal weight, overweight, obese, and extremely obese) to discern how BMI increase differs across group and across time., Methods: BMI was assessed in 1000 Chilean youth (52% female) at ages 5, 10, 15, and 21 years. Latent growth curve analysis modeled BMI trajectories from 5 to 21 years. Observer and maternal ratings assessed children's home and family environments and parenting at 1 and 10 years., Results: The four weight groups differed in acceleration of BMI increase starting at age 5, with bigger children getting bigger faster. Higher 21-year BMI related to family stress, father absence, maternal depression, frequent child confinement (in playpen), an unclean home environment at 1 year, and low provision for active stimulation and few stimulating experiences at 10 years. Accelerated BMI increase related to lower learning stimulation in the home at 1 year and less parental warmth and acceptance at child age 10., Conclusions: Home and family characteristics that reflect an absence of support for children's development were associated with overweight/obesity in young adulthood and accelerated BMI growth. Findings identify several home and family characteristics that can serve as preventive or intervention targets.

Aims: Metabolic syndrome (MetS) is a cluster of risk factors for cardiometabolic diseases. While cigarette smoking is associated with MetS in adults, young adulthood is an under-studied, susceptible period for developing long-term morbidity from MetS. We examined associations between cigarette smoking and MetS risk factors., Methods: We studied 430 participants in Santiago, Chile who have been followed in a longitudinal cohort since infancy and assessed in adolescence for MetS. Participants were evaluated at 22 years from May 2015 to July 2017. Adiposity, blood pressure, and blood samples were measured. MetS was defined using International Diabetes Federation criteria. A continuous MetS score was calculated using z-scores. Participants self-reported cigarette and alcohol consumption using standardized questionnaires. We used multivariate regressions to examine associations between smoking and MetS risk factors, adjusting for sex, MetS in adolescence, alcohol consumption, and socioeconomic status., Results: Thirteen percent of participants had MetS and 50% were current smokers. Among smokers, mean age of initiation was 14.9 years and consumption was 29 cigarettes weekly. Smokers had larger waist circumferences, higher BMIs, and lower high-density lipoprotein (HDL) cholesterol compared to non-smokers. Being a current smoker was significantly associated with higher waist circumference (β = 2.82; 95% CI 0.63, 5.02), lower HDL (β = - 3.62; 95% CI - 6.19, - 1.04), higher BMI (β = 1.22; 95% CI 0.16, 2.28), and higher MetS score (β = 0.13, 95% CI 0.02, 0.24)., Conclusions: Cigarette smoking at light levels (mean < 30 cigarettes weekly) was associated with MetS risk factors in a sample of Chilean young adults.

Background and Aim: Increased ferritin levels have been widely associated with cardiovascular risk in adults. Whether ferritin levels and their changes during childhood are related to metabolic syndrome (MetS) at adolescence is unknown. We aimed to evaluate these associations using levels of ferritin at 5, 10 and 16 years and their linear increases and patterns of sustained increased levels across childhood., Methods and Results: There were four samples evaluated according to non-missing values for study variables at each stage (5 years: 562; 10 years: 381; and 16 years: 567 children; non-missing values at any stage: 379). MetS risk was evaluated as a continuous Z score. Patterns of sustained increased ferritin (highest tertile) and slope of the change of ferritin per year across the follow-up were calculated. Ferritin levels in the highest versus lowest tertile at five and 16 years were significantly positively associated with MetS risk Z score at adolescence in boys and these associations were unaffected by adjustment for covariates. Having high, compared to low/moderate ferritin level at 2 or more time periods between 5 and 16 years was related to higher Mets Z-score in boys only [e.g. 5-10 years adjusted-beta (95 %CI):0.26 (0.05-0.48),P < 0.05]. In girls, ferritin Z score at 10 and 16 years was positively and independently associated with HOMA-IR Z score. In girls, the slope of ferritin per year in the highest tertile was positively associated with MetS risk Z-score [adjusted-beta (95 %CI):0.21 (0.05-0.38),P < 0.05]., Conclusions: Ferritin levels throughout childhood are positively related to cardiometabolic risk in adolescence, with associations varying by sex., (Copyright © 2019 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.)

Background: There is concern about the cognitive consequences of marijuana consumption., Aim: To assess the influence of current and past marijuana use and frequency on verbal learning and memory in a sample of adults aged 21 years old., Material and Methods: Marijuana use was assessed using a clinician administered interview in 654 participants (56% females), who reported frequency of use, age of first use and whether its use led to problems in their lives. The CogState International Shopping List was administered to assess learning and memory., Results: Seventy percent reported ever using marijuana, 46% consuming during the past year and 27% during the past 30 days. The latter scored significantly lower on delayed recall. Current and frequent use were significantly associated with lower accuracy in verbal learning and memory., Conclusions: In this cohort of adults aged 21 years old, marijuana use was prevalent and related to worse verbal memory.

Objective: The present longitudinal study assessed whether changes in socio-economic status (SES) from infancy to adolescence were associated with plasma lipoprotein concentrations in adolescence, of which low HDL-cholesterol (HDL-C) and high LDL-cholesterol (LDL-C), TAG and total cholesterol (TC) concentrations are associated with higher cardiovascular risk., Design: SES, assessed using the modified Graffar Index, was calculated at 1, 5, 10 and 16 years. Principal components factor analysis with varimax rotation extracted two orthogonal SES factors, termed 'environmental capital' and 'social capital'. Generalized linear models were used to analyse associations between environmental and social capital at 1 and 16 years and outcomes (HDL-C, LDL-C, TAG, TC) at 16 years, as well as changes in environmental and social capital from 1-5, 5-10, 10-16 and 1-16 years, and outcomes at 16 years., Setting: Santiago, Chile.ParticipantsWe evaluated 665 participants from the Santiago Longitudinal Study enrolled at infancy in Fe-deficiency anaemia studies and examined every 5 years to age 16 years., Results: Social capital in infancy was associated with higher HDL-C in adolescence. Environmental capital in adolescence was associated with higher LDL-C and TC during adolescence. Changing environmental capital from 1-16 years was associated with higher LDL-C. Changing environmental capital from 1-5 and 1-16 years was associated with higher TC., Conclusions: Improvements in environmental capital throughout childhood were associated with less healthy LDL-C and TC concentrations in adolescence. We found no evidence of associations between changing environmental capital and HDL-C or TAG, or changing social capital and HDL-C, LDL-C, TAG or TC.

Objective: Leptin is a pleiotropic hormone associated with learning and memory via brain receptors. However, elevated plasma leptin levels may impair cognitive and memory functions. Since individual differences in memory performance affect students' ability to learn, we aimed to study the relation between leptin status in adolescence and school performance., Design and Setting: We studied 568 adolescents aged 16-17 years from Santiago. A cross-sectional analysis was carried out on a birth cohort conducted in Santiago (Chile)., Primary and Secondary Outcome Measures: We measured serum leptin concentration using an enzyme-linked immunosorbent assay. Cut-offs from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) Study for 16-year-olds were used to define abnormally high leptin levels (hyperleptinaemia). Academic performance was measured using high-school grades and grade point average (GPA). Data were collected in 2009-2012; data analysis was performed in 2014., Results: 15% of participants had hyperleptinaemia. They had significantly lower school grades and GPA compared with participants with normal leptin levels (eg, GPA mean difference=33.8 points). Leptin levels were negative and significantly correlated with school grades in 9th, 10th and 12th. Similarly, it was negatively correlated with high-school GPA. After controlling for health, sociodemographic and education confounders, the chances of having a performance ≥75th centile in students having hyperleptinaemia were 32% (95% CI 0.19% to 0.89%) that of students having normal serum leptin concentration., Conclusions: In high school students, abnormally high levels of leptin were associated with poorer academic performance. These findings support the idea of a relationship between leptin and cognition. Further research is needed on the cognitive effects of leptin in younger populations., Competing Interests: Conflicts of Interest: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Objective: To explore associations between the nutritional quality of diet at age 16 years and academic performance in students from Santiago, Chile., Methods: We assessed the nutritional quality of diet, using a validated food frequency questionnaire, in 395 students aged 16.8 ± 0.5 years. Depending on the amount of saturated fat, fibre, sugar and salt in the foods, diet was categorized as unhealthy, fair or healthy. Academic performance was assessed using high school grade-point average (GPA) and tests for college admission in language and mathematics. Academic results on or above the 75th percentile in our sample were considered good academic performance. We tested associations between nutritional quality of diet and good academic performance using logistic regression models. We considered sociodemographic, educational and body-mass index (BMI) factors as potential confounders., Findings: After controlling for potential confounding factors, an unhealthy diet at age 16 years was associated with reduced academic performance. Compared to participants with healthy diets, those with unhealthy diets were significantly less likely to perform well based on language tests (odds ratio, OR: 0.42; 95% confidence interval, CI: 0.18-0.98) mathematics tests (OR: 0.35; 95% CI: 0.15-0.82) or GPA (OR: 0.22; 95% CI: 0.09-0.56)., Conclusion: In our sample, excessive consumption of energy-dense, low-fibre, high-fat foods at age 16 years was associated with reduced academic performance.

Objective: To determine patterns of satiety responsiveness and its relationship to eating in the absence of hunger (EAH), in a cohort of adolescents. We also assessed whether sex, body mass index and duration of breastfeeding, during infancy, predicted satiety responsiveness and eating behavior at 16 years., Methods: Adolescents (n=576) from a longitudinal cohort, which began as an iron deficiency anemia preventive trial, participated in an unlimited breakfast after an overnight fast, and reported satiety response on a visual analog scale after the meal, followed by an EAH procedure. Height, weight and body composition were measured before breakfast. Latent profile analysis generated profiles that captured individual differences in satiety responsiveness. Multivariable regressions, adjusted for potential confounders, evaluated the association between: (1) satiety responsiveness and EAH, and (2) breastfeeding in infancy, satiety responsiveness and EAH in adolescence., Results: Participants were on average 16.7-year old, 48% female, 37% overweight/obese and 76% were breastfed as the sole source of milk for <6 months. We found three latent profiles of satiety responsiveness: 1: 'responsive' (49%); 2: 'not responsive' (41%); 3: 'still hungry' (10%). Participants in the 'not responsive' or 'still hungry' profile were more likely to eat during the EAH procedure (odds ratio (OR)=2.5, 95% confidence interval (CI)=1.8-3.6). Being breastfed for <6 months was related to higher odds of being in the 'not responsive' or 'still hungry' profile (OR=1.8, 95% CI=1.2-2.6) and EAH (OR=2.2, 95% CI=1.4-3.3). Satiety responsiveness was not influenced by sex and overweight/obesity., Conclusion: After an ad libitum meal, we found varied satiety responses, which related to EAH. Furthermore, shorter breastfeeding duration was associated with poorer satiety response and higher consumption during an EAH procedure. Understanding if breastfeeding influences the development of satiety responsiveness and eating behavior may be important in an era characterized by abundant calorie-dense foods and a plethora of environmental cues promoting consumption.

The mild chronic inflammatory state associated with obesity may be an important link between adiposity and insulin resistance (IR). In a sample of 137 overweight and obese Chilean adolescents, we assessed associations between high-sensitivity C-reactive protein (hs-CRP), IR and adiposity; explored sex differences; and evaluated whether hs-CRP mediated the relationship between adiposity and IR. Positive relationships between hs-CRP, IR and 2 measures of adiposity were found. Hs-CRP was associated with waist circumference (WC) in boys and fat mass index (FMI) in girls. Using path analysis, we found that hs-CRP mediated the relationship between adiposity (WC and FMI) and the homeostatic model assessment of insulin resistance (HOMA-IR) (p < 0.05) in both sexes. Our novel finding is that inflammation statistically mediated the well described link between increased adiposity and IR.