Early Life Obesity Research Articles

Burden of Early Life Obesity and Its Relationship with Protein Intake in Infancy: The Middle East Expert Consensus.

Adequate nutrition in early life is proposed to shape a child’s future health by launching the growth trajectory in the proper direction, which helps to avoid negative metabolic programming effects. Protein intake during infancy and early childhood is of great importance, as it plays a key role in infant metabolic programming and the future risk of obesity. Breastfeeding provides the best nutrition in early life, with many benefits tailored for the baby, including the appropriate quantity and quality of proteins. Considering the high prevalence of childhood, and subsequent adult, obesity in the region, a virtual Middle East expert consensus meeting was held to discuss an effective approach for managing childhood obesity. Leading pediatric experts from Bahrain, Egypt, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates participated in the meeting. The experts discussed, debated, and agreed on certain directions, including the importance of educating parents, endorsing breastfeeding, and ensuring optimum quantity and quality intake of proteins in early life. This expert consensus may serve as the starting point for healthcare professionals in the region who are interested in shaping a healthy future for the generations to come.

Infant intakes of human milk branched chain amino acids are negatively associated with infant growth and influenced by maternal body mass index.

Branched-chain amino acids (BCAAs: isoleucine, leucine, and valine) and aromatic amino acids (AAAs: phenylalanine and tyrosine) are hypothesized to influence early-life obesity risk. To assess HM free amino acid (AA) concentrations and infant intakes of HM AAs from women with obesity (OB) compared to those with normal weight (NW) and determine the relationships between HM AA consumption and infant growth. HM samples were collected at 0.5 (n=151), 2 (n=129), and 6 (n=93) months postpartum from mothers with NW (body mass index [BMI]=18.5-24.9kg/m2 ) and OB (BMI > 30 kg/m2 ). HM AAs were quantified via mass spectrometry. Infant HM intake, anthropometrics and body composition were assessed. Linear mixed-effects models (LMEM) examined the relationships between maternal BMI and HM AA intakes, and HM AA intake and infant growth over the first 6months postpartum after adjusting for maternal and infant characteristics. Maternal BMI was positively associated with infant intakes of isoleucine, leucine, and AAAs across timepoints. HM AA intakes were positively associated with weight-for-length z-score, fat mass index, and fat-free mass index in infants (p < 0.05). Maternal BMI led to differences in HM AA composition, which was associated with infant body composition.

Relationship between pre-pregnancy maternal body mass index and infant weight trajectories in HIV-exposed and HIV-unexposed infants.

Maternal HIV and antiretroviral therapy (ART) exposure in utero may influence infant weight, but the contribution of maternal y body mass index (BMI) to early life overweight and obesity is not clear. To estimate associations between maternal BMI at entry to antenatal care (ANC) and infant weight through approximately 1year of age and to evaluate whether associations were modified by maternal HIV status, maternal HIV and viral load, breastfeeding intensity through 6months or timing of entry into ANC. We followed HIV-uninfected and -infected pregnant women initiating efavirenz-based ART from first antenatal visit through 12months postpartum. Infant weight was assessed via World Health Organization BMI and weight-for-length z-scores (WLZ) at 6weeks, 3, 6, 9 and 12months. We used multivariable linear mixed-effects models to estimate associations between maternal BMI and infant z-scores over time. In 861 HIV-uninfected infants (454 HIV-exposed; 407 HIV-unexposed), nearly 20% of infants were overweight or obese by 12months of age, regardless of HIV exposure status. In multivariable analyses, increasing maternal BMI category was positively associated with higher infant BMIZ and WLZ scores between 6weeks and 12months of age and did not differ by HIV exposure status. However, HIV-exposed infants had slightly lower BMIZ and WLZ trajectories through 12months of age, compared with HIV-unexposed infants across all maternal BMI categories. Differences in BMIZ and WLZ scores by HIV exposure were not explained by timing of entry into ANC or maternal viral load pre-ART initiation, but z-scores were slightly higher for HIV-exposed infants who were predominantly or exclusively versus partially breastfed. These findings suggest maternal BMI influences early infant weight gain, regardless of infant HIV exposure status. Intervention to reduce maternal BMI may help to address growing concerns about obesity among HIV-uninfected children.

The Effect of Growth Rate during Infancy on the Risk of Developing Obesity in Childhood: A Systematic Literature Review.

The prevalence of childhood obesity has been trending upwards over the last few decades. Recent evidence suggests that infant growth rate has the potential to increase the risk of obesity development during childhood. This systematic literature review aimed to summarise the existing evidence on the relationship between infant growth rate and subsequent childhood obesity. Studies were sought for that assessed the effect of infant growth rate on outcomes of overweight, obesity, BMI, waist circumference or body composition measures among a population group of children aged 2 to 12 years old. Data sources included PubMed, CINAHL, Web of Science and MedLine. Twenty-four studies were identified as eligible and included in this review, out of 2302 publications. The ADA Quality Checklist was used to assess the quality of individual studies. Ten studies received a positive result and 14 studies a neutral result. A narrative synthesis was completed to present study characteristics and results. Several independent positive associations were determined between rapid growth at different stages during infancy and overweight, obesity, BMI, waist circumference and body composition in childhood. Further investigation is required to determine if a specific period of infancy carries greater associations of risk with childhood outcomes. Determining an ideal rate of infants’ growth as a means to minimise the future risk of childhood obesity should be the focus of future research that will also inform early life obesity prevention strategies. Registration no.: CRD42021244029.

Early postnatal overnutrition impairs VO2max gains with moderate exercise and increase post-exercise muscle damage in adult male rats.

Exercise counteracts obesity effects, but information on how early-life obesity may affect long-term adaptation to exercise is lacking. This study investigates the impact of early-life postnatal overfeeding (PO) on animals' adaptation to exercise. Only male Wistar rats were used. On postnatal day (PN) 30, rats from control (NL-9 pups) or PO (SL-3 pups) litters were separated into four groups: NL-sedentary (NL-Se), NL-exercised (NL-Ex), SL-sedentary (SL-Se), and SL-exercised (SL-Ex). Exercised groups performed moderate-intensity exercise, running on a treadmill, from PN30 to PN90. Further experiments were carried out between PN90 and PN92. PO promoted obesity in SL versus NL rats (P < 0.05). Exercise reduced body weight (P < 0.001), body fat (P < 0.01), and improved glucose homeostasis in SL-Ex versus SL-Se. SL-Ex presented lower VO2max (P < 0.01) and higher post-exercise LDH (P < 0.05) compared to NL-Ex rats. Although moderate exercise counteracted obesity in SL rats, early-life overnutrition restricts fitness gains in adulthood, indicating that early obesity may impair animals' adaptation to exercise.

Prenatal antibiotic exposure and birth weight.

Current research suggests an association between antibiotic use in early life and later obesity. Less is known about prenatal antibiotic exposure and foetal growth. We investigated the association between prenatal antibiotic exposure and birth weight. Data from the Danish National Birth Cohort were linked to the Danish National Medical Birth Registry. Exposure was self-reported antibiotic use in pregnancy. Outcome was registered birth weight. Multivariable linear regression models were adjusted for confounders defined a priori. A total of 63 300 mother-child dyads from 1996 to 2002 were included. Overall, prenatal antibiotic exposure was not associated with birth weight (-8.90 g, 95%CI: -19.5- +1.64 g, p=0.10). Findings were similar for those born term and preterm. Antibiotic exposure in second to third trimester, compared to no exposure, was associated with lower birth weight (-12.6g, 95%CI: -24.1 to -1.1g, p=0.03). In sex-stratified analyses, there were no observed associations between antibiotics and birth weight. With further stratifications, prenatal antibiotic exposure and birth weight were associated in boys who were preterm (+91.0g, 95%CI: +6.8g- +175.2g, p=0.03) but not among girls who were preterm (-44.0g, 95%CI: -128.1 to +40.0g, p=0.30). Prenatal antibiotic exposure is not consistently associated with birth weight.

Obesity and Multiple Sclerosis—A Multifaceted Association

Background: Given the common elements in the pathophysiological theories that try to explain the appearance and evolution of obesity and multiple sclerosis, the association between the two pathologies has become an increasingly researched topic in recent years. On the one hand, there is the chronic demyelinating inflammation caused by the autoimmune cascade of multiple sclerosis, while on the other hand, according to the latest research, it has been shown that obesity shares an inflammatory component with most chronic diseases. Methods: The authors performed independent research of the available literature in the most important electronic databases (PubMed, Google Scholar, Embase, and Science Direct) in February 2021. After applying the exclusion criteria, the reviewers focused on the most relevant articles published during the last 10 years with respect to epidemiology and pathophysiology. Results: The data presented are a step forward in trying to elucidate the intricate relationship between obesity and MS, especially the causal relationship between childhood and adolescent obesity and MS, focusing on the epidemiological associations observed in the most relevant observational studies conducted in recent years. In the second part, the authors comment on the latest findings related to the pathophysiological mechanisms that may explain the correlations between obesity and multiple sclerosis, focusing also on the role of adipokines. Conclusions: Based on available epidemiological data, obesity in early life appears to be strongly associated with a higher risk of MS development, independent of other risk factors. Although much research has been done on the pathophysiology of obesity, MS, their possible common mechanism, and the role of adipokines, further studies are needed in order to explain what remains unknown. No relevant data were found regarding the association between obesity, disability (high EDSS score), and mortality risk in MS patients. Thus, we consider that this topic should be elucidated in future research.

The Role of Mendelian Randomization Studies in Deciphering the Effect of Obesity on Cancer.

Associations of obesity have been established for at least 11 cancer sites in observational studies, though some questions remain as to causality, strength of associations, and timing of associations throughout the life course. In recent years, Mendelian randomization (MR) has provided complementary information to traditional approaches, but the validity requires that the genetic instrumental variables be causally related to cancers only mediated by the exposure. We summarize and evaluate existing evidence from MR studies in comparison with conventional observational studies to provide insights into the complex relationship between obesity and multiple cancers. MR studies further establish the causality of adult obesity with esophageal adenocarcinoma and cancers of the colorectum, endometrium, ovary, kidney, and pancreas, as well as the inverse association of early life obesity with breast cancer. MR studies, which might account for lifelong adiposity, suggest that the associations in observational studies typically based on single measurement may underestimate the magnitude of the association. For lung cancer, MR studies find a positive association with obesity, supporting that the inverse association observed in some conventional observational studies likely reflects reverse causality (loss of lean body mass before diagnosis) and confounding by smoking. However, MR studies have not had sufficient power for gallbladder cancer, gastric cardia cancer, and multiple myeloma. In addition, more MR studies are needed to explore the effect of obesity at different timepoints on postmenopausal breast cancer and aggressive prostate cancer.

Exposure to obesogenic endocrine disrupting chemicals and obesity among youth of Latino or Hispanic origin in the United States and Latin America: A lifecourse perspective.

SummaryFollowing a 2019 workshop led by the Center for Global Health Studies at the Fogarty International Center on the topic of childhood obesity prevention and research synergies transpiring from cross‐border collaborations, we convened a group of experts in the United States and Latin America to conduct a narrative review of the epidemiological literature on the role of obesogenic endocrine disrupting chemicals (EDCs) in the etiology of childhood obesity among Latino youth in the United States and Latin America. In addition to summarizing and synthesizing results from research on this topic published within the last decade, we place the findings within a lifecourse biobehavioral framework to aid in identification of unique exposure‐outcome relationships driven by both biological and behavioral research, identify inconsistencies and deficiencies in current literature, and discuss the role of policy regulations, all with the goal of identifying viable avenues for prevention of early life obesity in Latino/Hispanic populations.

Cancer Progress and Priorities: Breast Cancer.

Breast cancer is the most commonly diagnosed invasive cancer among women both globally and within the United States and the number one cause of cancer-related deaths among women globally ([1, 2][1]). Less than 1% of diagnosed breast cancers occur in men ([2][2]) and, therefore, male breast cancer is

Body Mass Index Trajectories in the First 5 Years and Associated Antenatal Factors.

Background: The increasing prevalence of childhood obesity is an important public health issue and the development of obesity in early life and associated risk factors need to be better understood. The aim of this study was to identify distinct body mass index trajectories in the first 5 years of life and to examine their associations with factors identified in pregnancy, including metabolic parameters.Methods: BMI measurements from 2,172 children in Ireland enrolled in the BASELINE cohort study with BMI assessments at birth, 2, 6, and 12 months, and 2 and 5 years were analyzed. Growth mixture modeling was used to identify distinct BMI trajectories, and multivariate multinomial logistic regression was used to assess the association between these trajectories and antenatal factors.Results: Three distinct BMI trajectories were identified: normal (89.6%); rapid gain in the first 6 months (7.8%); and rapid BMI after 12 months (2.6%). Male sex and higher maternal age increased the likelihood of belonging to the rapid gain in the first 6 months trajectory. Raised maternal BMI at 15 weeks of pregnancy and lower cord blood IGF-2 were associated with rapid gain after 1 year.Conclusion: Sex, maternal age and BMI, and IGF-2 levels were found to be associated with BMI trajectories in early childhood departing from normal growth. Further research and extended follow-up to examine the effects of childhood growth patterns are required to understand their relationship with health outcomes.

Early Life Exposure to Food Insecurity is Associated with Changes in BMI During Childhood Among Latinos from CHAMACOS.

Early life exposures have been associated with obesity later in life. We aim to assess the association between early life exposure to food insecurity and change in BMI throughout childhood and adolescents. Food security status and growth variables from 243 Mother-child dyads from the Center for the Health Assessment of Mothers and Children of Salinas study were assessed 7 times over a 12-year period. Generalized log linear models with Poisson distributions and linear regression models were implemented to assess the associations between early life food insecurity and obesity and growth. Early life food insecurity was associated with a 0.43 (0.01, 0.82) kg/m2 decrease in BMI from age 2 to 3.5, and a 0.92kg/m2 (0.38, 1.46) increase in BMI among boys from ages 3.5 to 5, after adjusting for covariates. Sex and age modify the association between early life exposure to food insecurity and BMI.

Feeding style profiles are associated with maternal and infant characteristics and infant feeding practices and weight outcomes in African American mothers and infants

Much literature links individual feeding styles to infant feeding practices and growth; however, parents’ feeding styles are not discrete and may vary by context. We use latent profile analysis (LPA) as a person-centered approach to categorize infant feeding style patterns, test factors predicting profile membership, and examine if profiles are associated with infant feeding and weight. Additionally, we test the impact of a responsive feeding intervention on profile membership and stability. Data come from 270 African-American women and infants participating in the Mothers and Others Study, an early life obesity prevention intervention. LPA was used to categorize mothers across five constructs (laissez-faire, pressuring, restrictive, responsive and indulgent) measured at 28-weeks gestation and 3- and 15-months postpartum. Adjusted multinomial regression and regression models test the characteristics associated with profile membership and the associations between profile membership and breastfeeding and infant weight-for-age z-score (WAZ). We identified two groups (Positive and Less Responsive) prenatally, an additional group (High Controlling) at 3 months and a fourth group (High Indulgent) at 15 months. Several characteristics differed between the groups, including maternal age, income and depressive symptoms, infant sex and temperament, and treatment group. Mothers in the Positive group were more likely to breastfeed at 3 months. Infants with mothers in the High Controlling group had higher WAZ at 15 months. The intervention was associated with more Positive feeding practices at 15 months and a greater likelihood of remaining in the Positive group across the study. LPA identified profiles that are associated with maternal and infant characteristics and treatment group and with better feeding practices and growth outcomes, providing preliminary evidence that early intervention promoting more responsive feeding profiles may improve infant outcomes.

Influence of early-life body mass index and systolic blood pressure on left ventricle in adulthood – the Cardiovascular Risk in Young Finns Study

Background Increased left ventricular mass (LVM) predicts cardiovascular events and mortality. The objective of this study was to determine whether early-life exposures to body mass index (BMI) and systolic blood pressure (SPB) affects the left ventricular structure in adulthood. Methods We used longitudinal data from a 31-year follow-up to examine the associations between early-life (between ages 6–18) BMI and SPB on LVM in an adult population (N = 1864, aged 34–49). The burden of early-life BMI and SBP was defined as area under the curve. Results After accounting for contemporary adult determinants of LVM, early-life BMI burden associated significantly with LVM (3.61 g/SD increase in early-life BMI; [1.94 − 5.28], p < 0.001). Overweight in early-life (age- and sex-specific BMI values corresponding to adult BMI > 25 kg/m2) associated with 4.7% (2.5–6.9%, p < 0.0001) higher LVM regardless of BMI status in adulthood. Overweight in early-life combined with obesity in adulthood (BMI > 30kg/m2) resulted in a 21% (17.3–32.9%, p < 0.0001) increase in LVM. Higher early-life BMI was associated with a risk of developing eccentric hypertrophy. The burden of early-life SPB was not associated with adult LVM or left ventricular remodeling. Conclusions High BMI in early-life confers a sustained effect on LVM and the risk for eccentric hypertrophy independently of adulthood risk factors. KEY MESSAGES Excess in BMI in early-life has an independent effect on LVM and the risk of developing eccentric hypertrophy regardless of overweight status in adulthood. Systolic blood pressure levels in early-life did not have an independent effect on LVM or LV remodeling. The clinical implication of this study is that primary prevention of obesity in early-life may prevent the development of high LVM and eccentric hypertrophy.

Obesity at Age 6 Months Is Associated with Shorter Preschool Leukocyte Telomere Length Independent of Parental Telomere Length

To assess whether early modifiable dietary factors and obesity measures are associated with leukocyte telomere length at 3-5years of age after controlling for the heritability of leukocyte telomere length in a prospective cohort of low-income Latina mothers and their children in San Francisco. We analyzed data from the Latinx, Eating and Diabetes cohort, a prospective study of 97 woman-infant dyads. We used linear regression models to evaluate associations between early dietary factors and obesity measures and child leukocyte telomere length at 3-5years of age. Multivariable models included child age at the time of telomere collection, breastfeeding at 6months (yes/no), obesity at 6months, maternal education, child sex, and maternal and paternal leukocyte telomere length. Data for 73 of the 97 children at 3-5years of age were analyzed. Any breastfeeding at 6months was positively associated (β=0.14; P=.02) and obesity at 6months was negatively associated (β=-0.21; P<.001) with leukocyte telomere length in bivariate analyses. In multivariable models including parental leukocyte telomere length, obesity at 6months was associated with a shorter leukocyte telomere length at 3-5years of age (β=-0.15; P=.02). Analyses of dietary factors showed high flavored milk consumption at 3years of age was associated with shorter leukocyte telomere length after adjustment for possible confounders. In a low-income Latinx population, obesity at 6months of age is negatively associated with cellular health at 3-5years of age after controlling for genetic factors (parental leukocyte telomere length) associated with leukocyte telomere length. Early life obesity may be more deleterious for cellular health than obesity later in childhood.

Adult obesity and its complications: a pediatric disease?

Approximately 2.6 million people die each year secondary to obesity related diseases. The risk of developing serious comorbidities depends on the age of onset as well as duration of obesity. In this review, we discuss trends in BMI trajectories from early childhood to adulthood with latest evidence on comorbidities in adulthood stemming from pediatric obesity and benefits of early intervention and treatment in childhood obesity. Childhood obesity poses high risk of metabolic and cardiovascular disorders like type 2 diabetes, hypertension, atherosclerosis, coronary artery disease, and some types of cancer in adulthood. Early life obesity also increases risks of developing menstrual irregularities, infertility, and pregnancy complications. Several grave concerns including malignancies, autoimmune disorders, higher asthma morbidity, and psychiatric implications are found to be associated with childhood obesity. Disease outcomes can be transgenerational, causing suboptimal health in children of mothers with obesity. Encouragingly, many risks associated with childhood obesity can be reduced, delayed, or even reversed by early resolution of obesity necessitating close BMI monitoring and treatment early. Early identification and aggressive management of childhood obesity is critical in prevention of debilitating comorbidities in adult life. http://links.lww.com/COE/A19.

Evaluating the pathways linking complementary feeding practices to obesity in early life.

The complementary feeding period, when solids and liquids other than breast milk and formula are added to the infant diet, is an important development window shaping infant growth and weight gain, metabolic development, and lifelong eating practices. Yet, relatively little is known about how the timing and types of foods offered to infants at this stage may shape their growth and subsequent risk of developing obesity. This narrative review describes the existing literature on complementary feeding practices, discusses potential biological and behavioral pathways linking complementary feeding practices to the development of obesity, and offers potential avenues for intervention. While further research is needed to more fully understand optimal complementary feeding practices, existing evidence supports the importance of healthful early feeding practices in the physiological and behavioral regulation of growth and metabolism and the need for early intervention to prevent the development of obesity.

Abstract LB-157: Obesity at early adulthood increases subsequent risk of gastric cancer in high incidence nation: Results from the Health Examinees-Gem (HEXA-G) study

Abstract Background: The global trend of obesity, or the “obesity epidemic,” is not confined to adults. The increasing rates of obesity at young age signifies potential burden to our society as a whole, and requires prompt attention. Although emerging evidence has indicated a possible link of obesity in early life to subsequent cancer risks, the association with gastric cancer remains largely unknown, especially among the populations with high incidence rates of gastric cancer. Objective: Using data from the Health Examinees (HEXA) study of Korea, this study aimed to investigate the association of obesity at younger age (ages 18-20 and 35) with the later risk of gastric cancer in a population with high incidence rate of gastric cancer. Method: Included were 114,155 cancer-free subjects who participated in the large-scale prospective cohort study of the Health Examinees-Gem (HEXA-G) study during 2004-2013. Multivariate Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for gastric cancer risk associated with body mass index (BMI) at age 18-20 and 35. To consider substantial differences in incidence rates between men and women, the overall associations were further evaluated, separately by sex. Results: During a median follow-up period of 6.2 years, 851 gastric cancer cases (476 men and 375 women) were identified. When compared to normal BMI (18.5 - 23.0kg/m2), obesity (BMI ≥30kg/m2) at age 35 was significantly associated with increased risk of gastric cancer later in life: HR (95% CI) = 2.60 (1.57-4.33) for total participants, 2.11 (1.03-4.34) for men, and 3.82 (1.86-7.86) for women. No significant associations were found for obesity at late adolescence in both men and women. Conclusion: Our findings suggest that obesity in early adulthood may be associated with increased risk of gastric cancer. Preventing obesity in early life may help reduce the health burden of gastric cancer in later life. Citation Format: Hwi-Won Lee, Woo-Kyoung Shin, Jae Jeong Yang, Minkyo Song, Aesun Shin, Jong-koo Lee, Daehee Kang. Obesity at early adulthood increases subsequent risk of gastric cancer in high incidence nation: Results from the Health Examinees-Gem (HEXA-G) study [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-157.

Spatial and Social Determinants of Household Food Environments in Central North Carolina

Abstract Objectives This study explores sociodemographic predictors of household food environments and tests the hypothesis that they are associated with community food environments. Methods Data are from the baseline visit of the Mothers &amp; Others study, an early life obesity prevention trial among 430 African-American mothers in central North Carolina. Healthy Homes Survey (HHS) data assessed household food availability, type and variety. Exploratory factor analysis (EFA) with oblique rotations consolidated 45 HHS variables into household food environment (HFE) types. From data retailer InfoUSA we obtained geocoded data containing all food outlets in the study area to assess proximity and density of food outlets near households. Linear regressions tested associations between maternal and household characteristics and HFE factor scores. Adjusted models tested the association between HFE factor scores, community food environment exposures, and sociodemographic interactions. Results EFA retained four HFE types: Factor 1, the healthiest, contained fresh fruits/vegetables (F/V), Factor 2 contained canned F/V, sweets, and salty snacks, Factor 3 contained frozen F/V, candy and sweetened drinks and Factor 4, the least healthful, contained (diet) soda, candy and sweets. SNAP participation was associated with a 23% (CI: –0.42, –0.04) z-score reduction for Factor 1 only. Each additional education level was associated with a 20% (CI: 0.10, 0.31) and 18% (CI: 0.07, 0.29) z-score increase for Factors 1 and 3, respectively. Each 1-unit increase in household size and maternal age accompanied a 6% (CI: 0.001, 0.11) and 3% (CI: 0.01, 0.05) respective z-score increase for Factor 3 only. Each additional dollar store within a 1-mile radius was associated with a 13.8% (CI: –0.22, –0.06) z-score reduction for Factor 3 while each mile closer to a grocery store accompanied a 12.1% (CI: 0.003, 0.24) z-score increase for Factor 3. Among households not receiving SNAP or WIC benefits, each mile closer to a grocery store accompanied a 27% (CI: 0.05, 0.47) and 30% (CI: 0.04, 0.55) respective z-score increase for Factor 1. Conclusions Healthy food environments are associated with local food outlet access and household characteristics. However, enrollment in nutrition assistance programs strongly modifies this relationship. Funding Sources National Institute of Child Health and Human Development.

Bedtime, body mass index and obesity risk in preschool-aged children.

Although sleep duration is a risk factor for obesity in young children, less is known about other aspects of sleep health, including bedtime, on obesity risk. To determine whether bedtime is associated with body mass index (BMI) z-score or obesity risk in children ages 2 to 5 years, and to determine if associations are independent of sleep duration. Cohort analyses were undertaken using three early life obesity prevention trials (POI, INSIGHT, Healthy Beginnings) and a longitudinal cohort study (HOME). Bedtime was assessed by questionnaire and BMI through clinical measurement between 2 and 5 years in 1642 children. Adjusted regression models examined whether BMI z-score and obesity (BMI z-score ≥ 2) were associated with bedtime, nocturnal sleep time and 24-hour sleep time. A discrete mixture model categorized children into bedtime trajectory groups across time points. Bedtime was inconsistently associated with BMI z-score. Although each hour later of bedtime was associated with greater odds of obesity at ages 3 (OR; 95% CI: 1.05; 1.003, 1.10) and 5 (1.35; 1.08, 1.69) years, odds were attenuated after adjustment for nocturnal or 24-hour sleep time. Longer nocturnal sleep duration at 2 years was associated with lower odds of obesity (OR 0.90; 0.86, 0.94), as was longer 24-hour sleep duration at 3 years in girls (0.70; 0.62, 0.78). BMI z-score and odds of obesity were not significantly different between 'early to bed' and 'late to bed' trajectory groups. Timing of bedtime appears inconsistently related to obesity in young children, possibly via influencing overall sleep duration.