Changes in adiposity among children and adolescents in the United States, 1999-2006 to 2011-2018

The Contributions of delivery mode and intrapartum antibiotic exposure to body mass index among children through 5 years of age

OBJECTIVE

To investigate independent effects of group B Streptococcus (GBS) intrapartum antibiotic prophylaxis (IAP) and cesarean delivery (CD) on body mass index (BMI) during early childhood.

STUDY DESIGN

Retrospective cohort study of infants (n = 157,820) born 2007-2015 in an integrated healthcare system. Exposures were delivery mode (CD or vaginal delivery [VD]) and GBS IAP exposure. CD was further divided into elective CD (without labor or rupture of membrane [ROM]) or unscheduled CD (following labor and/or ROM). BMI over 5 years was compared using non-linear multivariate models with B-splines, adjusted for demographics, maternal medical and obstetrical factors, and childhood antibiotic exposure.

RESULTS

At age 5 years, unscheduled CD without GBS IAP (Δ BMI 0.11 kg/m2, 95 % CI 0.06 to 0.16, p < 0.0001) and unscheduled CD with GBS IAP (Δ BMI 0.24 kg/m2, 95 % CI 0.11 to 0.36 kg/m2, p = 0.0002) were positively associated with higher BMI compared to their VD counterparts, respectively. No BMI difference was observed between children born by elective versus unscheduled CD. GBS IAP exposure was positively associated with increased BMI compared to non-exposed births in both VD (Δ BMI 0.07 kg/m2, 95 % CI 0.02 to 0.13 kg/m2, p = 0.0125) and CD (Δ BMI 0.22 kg/m2, 95 % CI 0.09 to 0.35 kg/m2, p = 0.0009).

CONCLUSIONS

Based on our findings, the widespread administration of GBS IAP and birth by cesarean delivery independently contribute to a significant upshift in body weight early in life that compares to or is higher than the annual increase in BMI in U.S. children on a population level.

Changes in BMI and Fat Mass and Nutritional Behaviors in Children Between 10 and 14 Years of Age

Background/Objectives: Unhealthy nutritional behaviors and excess body weight constitute a serious challenge for public health in children and adolescents. The aim of this study was to examine changes in body mass index (BMI), body fat mass (FM), and nutritional behaviors in the same group of children during a 4-year observation between 10 and 14 years of age including the period of the COVID-19 pandemic. Methods: BMI and FM using bioelectrical impedance were assessed. To assess nutritional behavior, a questionnaire on eating behavior was used. The study was carried out in a group of 250 children, starting from the age of 10 and finishing at the age of 14. The measurements were collected in the years 2017 and 2021. The results were compared and analyzed. Results: Excessive BMI (overweight and obesity) was more often found in girls (28.29%) than boys (23.63%), while normal body weight was more often found in boys (65.76%) than girls (60.96%). Between the initial and final assessments, the percentage of children with normal body mass decreased from 65.65% to 61.07%. Excessive BMI (overweight and obesity) increased from 27.09% to 29.50% in girls, and from 21.26% to 26.00% in boys. The mean percentage of FM was higher in girls than boys (23.17% vs. 16.20%, respectively). The mean FM decreased from 17.80% to 14.60% in boys and increased from 21.77% to 24.57% in girls. Poor nutritional behaviors were observed in 20.35% of children, more often in boys (22.25%) than in girls (18.50%). Between the initial and final assessments, an increase in the mean consumption of fruit, whole-grain bread, and milk was noted. These were products that should be consumed more often to demonstrate a healthy diet. However, the consumption of products that should be limited for a healthy diet, such as fried flour dishes, fried meat dishes, fatty cheeses, butter, fast food, sweets, and carbonated drinks, also increased. Boys more often than girls consumed red meat and poultry meat, eggs, butter, and fast food, while girls more often than boys consumed fruit, vegetables, yogurts, cottage cheese, wholemeal bread, fruit, and sweets. Conclusions: Children usually showed moderate nutritional behavior. After four years, there was a significant increase in the consumption of fruit and whole-grain bread, i.e., products that should be consumed as part of a healthy diet, as well as fried flour and meat dishes, fatty cheeses, butter, fast food, and sweets, i.e., products whose consumption should be limited. With age, the percentage of children showing unfavorable nutritional behaviors and excessive body weight increased. More extreme levels of overweight and obesity and higher body fat contents were found in girls than boys. Although girls' nutritional behaviors were healthier, they were at a higher risk of excessive body weight. Increased promotion of a healthy diet and regular monitoring of body fat content in school-aged children is strongly recommended.

2025 Heart Disease and Stroke Statistics: A Report of US and Global Data From the American Heart Association

BACKGROUND

The American Heart Association (AHA), in conjunction with the National Institutes of Health, annually reports the most up-to-date statistics related to heart disease, stroke, and cardiovascular risk factors, including core health behaviors (smoking, physical activity, nutrition, sleep, and obesity) and health factors (cholesterol, blood pressure, glucose control, and metabolic syndrome) that contribute to cardiovascular health. The AHA Heart Disease and Stroke Statistical Update presents the latest data on a range of major clinical heart and circulatory disease conditions (including stroke, brain health, complications of pregnancy, kidney disease, congenital heart disease, rhythm disorders, sudden cardiac arrest, subclinical atherosclerosis, coronary heart disease, cardiomyopathy, heart failure, valvular disease, venous thromboembolism, and peripheral artery disease) and the associated outcomes (including quality of care, procedures, and economic costs).

METHODS

The AHA, through its Epidemiology and Prevention Statistics Committee, continuously monitors and evaluates sources of data on heart disease and stroke in the United States and globally to provide the most current information available in the annual Statistical Update with review of published literature through the year before writing. The 2025 AHA Statistical Update is the product of a full year's worth of effort in 2024 by dedicated volunteer clinicians and scientists, committed government professionals, and AHA staff members. This year's edition includes a continued focus on health equity across several key domains and enhanced global data that reflect improved methods and incorporation of ≈3000 new data sources since last year's Statistical Update.

RESULTS

Each of the chapters in the Statistical Update focuses on a different topic related to heart disease and stroke statistics.

CONCLUSIONS

The Statistical Update represents a critical resource for the lay public, policymakers, media professionals, clinicians, health care administrators, researchers, health advocates, and others seeking the best available data on these factors and conditions.

Using Parks and Recreation Providers to Enhance Obesity Treatment: A Randomized Controlled Trial

OBJECTIVE

Intensive health behavior and lifestyle treatment (IHBLT) is recommended for children aged 6-18 years with obesity. The objective was to evaluate the effectiveness of Fit Together, a health care and parks and recreation partnership to deliver IHBLT.

METHODS

A randomized controlled trial was conducted from 2018 to 2021. Youths (aged 5-17 years) with obesity were recruited from primary care clinics and randomized to a waitlist control or Fit Together (ie, clinical obesity care plus group-based lifestyle sessions at a local recreation center). Primary outcomes, child body mass index relative to the 95th percentile (BMIp95) and submaximal heart rate, were collected at baseline and 6 months. Generalized estimating equation models were used to assess changes in primary outcomes for those affected and not affected by COVID-19 study disruptions.

RESULTS

Participants (n = 255) had a mean (SD) age of 10.0 (3.0) years, were 39% Hispanic, and were 38% non-Hispanic Black. Intervention youths not affected by COVID-19 disruptions experienced a significant decrease in BMIp95 (β = -3.05; 95% confidence interval [CI], -5.08 to -1.01) compared with controls. There was no difference in BMIp95 between intervention and control youths affected by COVID-19 disruptions (β = -3.25; 95% CI, -7.98 to 1.48). For the entire cohort, intervention youths had a significant decrease in BMIp95 compared with control youths (β = -3.32; 95% CI, -5.69 to -0.96). Submaximal heart rate was only available for the nondisrupted group, but there was no difference between intervention and control youths (β = -7.18; 95% CI, -16.12 to 1.76).

CONCLUSION

Effective child obesity treatment can be implemented in local communities through a partnership between clinical practices and parks and recreation providers. Future research will explore this model in combination with newer, more effective obesity treatments.

Associations between hypovitaminosis D, adiposity indices and insulin resistance in adolescents: mediation analyses from NHANES 2011-2018

BACKGROUND

As all kown, both hypovitaminosis D and insulin resistance (IR) have been linked to adiposity. However, the extent of adiposity's mediating influence on the hypovitaminosis D-IR relationship among adolescents remains to be elucidated. Additionally, the intricate effects of obesity and blood lipid profiles on IR are not yet fully understood.

METHODS

We conducted a comprehensive analysis of NHANES data from 2011 to 2018, examining the correlation between adiposity indices such as Body Mass Index (BMI), Fat Mass Index (FMI, defined as the ratio of fat mass to height squared), hypovitaminosis D, and IR. We employed the XGBoost algorithm to identify key factors significantly influencing IR, thereby deepening our insight into the link between adiposity and insulin resistance. Furthermore, we applied mediation analysis to precisely assess the mediating role of adiposity indices in the relationship between hypovitaminosis D and IR.

RESULTS

Our study revealing significant correlations between adiposity indices, hypovitaminosis D, and IR after variable adjustment. Notably, subgroup analysis indicated a pronounced hypovitaminosis D -adiposity association in female adolescents, which was not observed in males. The XGBoost algorithm pinpointed obesity and blood lipid indicators significantly affecting IR, with total fat mass, triglyceride, cholesterol, BMI, and FMI ranked by descending importance. Mediation analysis disclosed that adiposity indices mediate a substantial portion of the hypovitaminosis D -IR relationship, with FMI (43.84%, p < 0.001) and BMI (40.87%, p < 0.001) showing significant mediating effects.

CONCLUSION

The study confirmed significant correlations between adiposity indices, hypovitaminosis D, and IR in adolescents, with gender-specific differences in the hypovitaminosis D -adiposity link. Cholesterol was found to have a more substantial influence on IR than BMI and FMI. Furthermore, FMI was identified as a more potent mediator of the hypovitaminosis D-IR relationship compared to BMI, highlighting its importance in the pathophysiology of insulin resistance in adolescents.

The Cross-Sectional Relation of Body Mass Index to Adiposity among 8- to 19-Year-Olds within Several Races and Ethnicities

OBJECTIVE

To assess the screening ability of a high body mass index (BMI) for high adiposity among 8- to 19-year-olds.

STUDY DESIGN

This cross-sectional study included 6454 National Health and Nutrition Survey participants from 2011 through 2018. Fat and lean mass were measured with dual-energy X-ray absorptiometry. We expressed adiposity as fat mass index (FMI, kg ÷ m2) and %fat.

RESULTS

Based on the Centers for Disease Control and Prevention 95th percentile, a high BMI correctly classified a high FMI for about 95% of participants in each racial and ethnic group. About 81% (Blacks) to 90% (Hispanics) of participants with a high BMI also had a high FMI. Further, children with a high BMI were 17 (Hispanics) to 46 (Blacks) times more likely to have a high FMI than those with a "normal" BMI. The screening ability of high BMI for high %fat was weaker because levels of %fat are influenced by both fat mass (numerator) and lean mass (denominator).

CONCLUSIONS

Despite differences in body composition, a high BMI is a very good screening tool for identifying high FMI not only among White 8- to 19-year-olds but also among Asians, Blacks, and Hispanics. Compared with %fat, FMI is likely a better adiposity metric among children and adolescents.

Differences in physical activity, sedentary time, and anthropometric variables among children and adolescents: The TUBON project

BACKGROUND

Although physical inactivity may lead to increasing obesity prevalence, research on anthropometric variables changes based on physical activity (PA) in children and adolescents is limited. PA decreases with age, while sedentary behavior increases. The study aimed to examine differences in objectively measured sedentary time, light-intensity physical activity (LPA), and moderate-to-vigorous intensity physical activity (MVPA) between children and adolescents, and the differences in the percentiles of anthropometric variables between physically active and inactive groups according to World Health Organization PA recommendations.

METHODS

A total of 759 participants aged 6-17 years (boys, n=358; girls, n=401) were included in the study. The ActiGraph wGT3x-BT accelerometer was used to measure sedentary time, LPA, and MVPA. Height, weight, waist circumference (WC), triceps skinfold thickness (T-SFT), and medial-calf skinfold thickness (M-SFT) were measured. Body fat percentage (BF%) and body mass index (BMI) were calculated, and the percentiles of anthropometric variables were categorized.

RESULTS

The findings showed that children had less sedentary time and a higher LPA than adolescents for both genders (p<0.05). Children had a higher MVPA than adolescents in girls (p<0.05), but the difference was insignificant in boys (p>0.05). In boys, physically active children were in lower percentiles for T-SFT and BF% than those who did not (p<0.05). In boys, adolescents who were physically inactive were in higher percentiles for BMI, T-SFT, M-SFT, and BF% (p<0.05). In addition, in girls, adolescents who were physically active were in lower percentiles of BMI, M-SFT, and BF%, whereas children who were physically active were in lower percentiles of M-SFT and BF% (p<0.05).

CONCLUSION

Sedentary time increases while PA decreases with age. Children and adolescents who met the WHO PA recommendation had lower percentiles of anthropometric variables, indicating the importance of PA in preventing obesity in these age groups.

Awareness and Use of MyPlate Among US Adults With Young Children

OBJECTIVE

To examine awareness, information-seeking, and use of MyPlate among US adults with young children.

DESIGN

Secondary analysis of cross-sectional data from the 2015-2018 National Health and Nutrition Examination Survey (NHANES).

PARTICIPANTS

US adults aged 18-45 years with children ≤5 years.

VARIABLES MEASURED

Adults reported sociodemographic characteristics and whether they had heard of MyPlate, looked online for MyPlate information, or tried to follow the MyPlate plan.

ANALYSIS

Logistic regression models estimated MyPlate awareness, information-seeking, and use by sociodemographic characteristics. Analyses were weighted to represent adults with young children nationally.

RESULTS

Twenty-nine percent of US adults with young children were aware of MyPlate. MyPlate awareness was lower among men, racial/ethnic minorities, adults with less education, adults who speak a language other than English, and SNAP/WIC recipients. Among those who knew of MyPlate, 39% sought MyPlate information online, and 33% had tried to use the MyPlate plan. Men were less likely to look online for or follow the MyPlate plan than women. Mexican-American adults and WIC recipients were more likely to have tried to follow the MyPlate plan.

CONCLUSIONS

MyPlate is an underutilized resource among families with young children. Efforts are needed to disseminate and encourage the use of MyPlate, particularly among marginalized groups.

A Randomized Trial of Inspiratory Training in Children and Adolescents With Obesity

Introduction: Children with obesity suffer excess dyspnea that contributes to sedentariness. Developing innovative strategies to increase exercise tolerance and participation in children with obesity is a high priority. Because inspiratory training (IT) has reduced dyspnea, we sought to assess IT in children with obesity. Methods: We conducted a 6-week randomized IT trial involving 8- to 17-year-olds with obesity. Participants were randomized 1:1 to either high [75% of maximal inspiratory pressure (MIP)] or low resistance control (15% of MIP) three times weekly. Assessments included adherence, patient satisfaction, and changes in inspiratory strength and endurance, dyspnea scores and total activity level. Results: Among 27 randomized, 24 (89%) completed the intervention. Total session adherence was 72% which did not differ between treatment groups. IT was safe, and more than 90% felt IT benefitted breathing and general health. IT led to a mean improvement (95% CI) in inspiratory strength measured by MIP of 10.0 cm H2O (-3.5, 23.6; paired t-test, p = 0.139) and inspiratory endurance of 8.9 (1.0, 16.8; paired t-test, p = 0.028); however, there was no significant difference between high- and low-treatment groups. IT led to significant reductions in dyspnea with daily activity (p < 0.001) and in prospectively reported dyspnea during exercise (p = 0.024). Among the high- versus low-treatment group, we noted a trend for reduced dyspnea with daily activity (p = 0.071) and increased daily steps (865 vs. -51, p = 0.079). Discussion: IT is safe and feasible for children with obesity and holds promise for reducing dyspnea and improving healthy activity in children with obesity. Breathe-Fit trial NCT05412134.

Role of Adverse Childhood Experiences in the Onset of Overweight/Obesity

PURPOSE OF REVIEW

The goal of this chapter was to summarize the literature on childhood adversity and obesity, discuss treatment implications with a case example, and provide recommendations for trauma-informed care for clinicians who work with individuals living with obesity.

RECENT FINDINGS

Adversity in childhood is related directly and indirectly to obesity development. Upstream contributors like adverse childhood experiences (ACEs) and other factors can lead to experiences of toxic stress and increased allostatic load, resulting in downstream effects of obesity and other chronic health conditions. A well-established literature has linked ACEs and obesity suggesting complex interactions between genetic, biological, behavioral, mental health, social, and environmental factors and obesity. Trauma-informed care strategies can be used to optimize care for individuals living with obesity. Care pathways should include individual (clinician) and systemic (organizational) evidence-based interventions.

Trends in cardiovascular risk factor prevalence, treatment, and control among US adolescents aged 12 to 19 years, 2001 to March 2020

BACKGROUND

Early-life cardiovascular risk factors (CVRFs) are known to be associated with target organ damage during adolescence and premature cardiovascular morbidity and mortality during adulthood. However, contemporary data describing whether the prevalence of CVRFs and treatment and control rates have changed are limited. This study aimed to examine the temporal trends in the prevalence, treatment, and control of CVRFs among US adolescents over the past 2 decades.

METHODS

This is a serial cross-sectional study using data from nine National Health and Nutrition Examination Survey cycles (January 2001-March 2020). US adolescents (aged 12 to 19 years) with information regarding CVRFs (including hypertension, elevated blood pressure [BP], diabetes, prediabetes, hyperlipidemia, obesity, overweight, cigarette use, inactive physical activity, and poor diet quality) were included. Age-adjusted trends in CVRF prevalence, treatment, and control were examined. Joinpoint regression analysis was performed to estimate changes in the prevalence, treatment, and control over time. The variation by sociodemographic characteristics were also described.

RESULTS

A total of 15,155 US adolescents aged 12 to 19 years (representing ≈ 32.4 million people) were included. From 2001 to March 2020, there was an increase in the prevalence of prediabetes (from 12.5% [95% confidence interval (CI), 10.2%-14.9%] to 37.6% [95% CI, 29.1%-46.2%]) and overweight/obesity (from 21.1% [95% CI, 19.3%-22.8%] to 24.8% [95% CI, 21.4%-28.2%]; from 16.0% [95% CI, 14.1%-17.9%] to 20.3% [95% CI, 17.9%-22.7%]; respectively), no improvement in the prevalence of elevated BP (from 10.4% [95% CI, 8.9%-11.8%] to 11.0% [95% CI, 8.7%-13.4%]), diabetes (from 0.7% [95% CI, 0.2%-1.2%] to 1.2% [95% CI, 0.3%-2.2%]), and poor diet quality (from 76.1% [95% CI, 74.0%-78.2%] to 71.7% [95% CI, 68.5%-74.9%]), and a decrease in the prevalence of hypertension (from 8.1% [95% CI, 6.9%-9.4%] to 5.5% [95% CI, 3.7%-7.3%]), hyperlipidemia (from 34.2% [95% CI, 30.9%-37.5%] to 22.8% [95% CI, 18.7%-26.8%]), cigarette use (from 18.0% [95% CI, 15.7%-20.3%] to 3.5% [95% CI, 2.0%-5.0%]), and inactive physical activity (from 83.0% [95% CI, 80.7%-85.3%] to 9.5% [95% CI, 4.2%-14.8%]). Sex and race/ethnicity affected the evolution of CVRF prevalence differently. Whilst treatment rates for hypertension and diabetes did not improve significantly (from 9.6% [95% CI, 3.5%-15.8%] to 6.0% [95% CI, 1.4%-10.6%]; from 51.0% [95% CI, 23.3%-78.7%] to 26.5% [95% CI, 0.0%-54.7%]; respectively), BP control was relatively stable (from 75.7% [95% CI, 56.8%-94.7%] to 73.5% [95% CI, 40.3%-100.0%]), while glycemic control improved to a certain extent, although it remained suboptimal (from 11.8% [95% CI, 0.0%-31.5%] to 62.7% [95% CI, 62.7%-62.7%]).

CONCLUSIONS

From 2001 to March 2020, although prediabetes and overweight/obesity increased, hypertension, hyperlipidemia, cigarette use, and inactive physical activity decreased among US adolescents aged 12 to 19 years, whereas elevated BP, diabetes, and poor diet quality remained unchanged. There were disparities in CVRF prevalence and trends across sociodemographic subpopulations. While treatment and control rates for hypertension and diabetes plateaued, BP control were stable, and improved glycemic control was observed.

Effects of dietary sugar restriction on hepatic fat in youth with obesity

Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease in children. Like adults, children can develop the progressive form of NAFLD, nonalcoholic steatohepatitis (NASH), which is characterized by hepatic inflammation, often in the presence of fibrosis. Children with NAFLD are at higher risk of liver-related complications, metabolic dysfunction, and cardiovascular disease in adulthood. Many factors contribute to the escalating prevalence of NAFLD in the pediatric population, among which are an array of dietary patterns such as overnutrition, poor diet quality, and heavy consumption of fat and sugar, including fructose. Findings from an increasing number of epidemiological studies support a connection between high habitual sugar consumption and NAFLD, especially within the context of obesity, but these studies are not able to demonstrate whether sugar is a contributing factor or instead an indicator of an overall poor diet (or lifestyle) quality. To date, only four randomized controlled dietary interventions assessing the effects of sucrose/fructose restriction on hepatic fat fraction in youth with obesity have been published. The objectives of this review are to summarize the key findings from these dietary interventions to achieve a better understanding of the strength of the relationship between dietary sugar restriction and liver fat reduction, despite their inherent limitations, and to discuss the potential impact of weight loss and fat mass reduction on improvement in hepatic steatosis.

Understanding health behaviors that modify the risk for obesity in ADHD

OBJECTIVE

Research provides support for the associated risk of inadequate sleep duration, limited physical activity, and excessive media use in attention-deficit/hyperactivity disorder (ADHD) and obesity. The present study aims to (1) examine the association between ADHD and overweight or obese status (OW/OB); (2) comprehensively examine sleep duration, physical activity, and media use as potential moderators of OW/OB; and (3) examine the moderating effects of these health behaviors cross-sectionally by comparing medicated youth with ADHD, unmedicated youth with ADHD, and youth without ADHD.

METHODS

Data were acquired from the 2018 and 2019 National Survey of Children's Health, a nationally representative survey of caregivers conducted across the United States. The current study used data for youth 11-17 years old with a final sample size of 26,644. Hours of sleep, physical activity, and media use per day were dichotomized based on national recommendation guidelines for each health behavior (i.e., either meeting or not meeting guidelines).

RESULTS

The OW/OB prevalence rate was 7% greater among unmedicated youth with ADHD than among medicated youth with ADHD. Medicated youth with ADHD and peers without ADHD had similar OW/OB rates. Among medicated youth with ADHD, physical activity, sleep duration, and media use did not contribute to OW/OB risk after controlling for family poverty level. However, among unmedicated youth with ADHD, meeting sleep duration guidelines was linked to a lower OW/OB risk.

CONCLUSION

Overall, findings suggest that clinical providers and parents may wish to prioritize improved sleep duration in the management of OW/OB risk in youth with ADHD.

Increasing disparities in obesity and severe obesity prevalence among public elementary and middle school students in New York City, school years 2011-12 through 2019-20

Recent national trends in the United States indicate a significant increase in childhood obesity, a major public health concern with documented physical and mental comorbidities and sociodemographic disparities. We aimed to estimate the prevalence of obesity and severe obesity among youth in New York City (NYC) before the COVID-19 pandemic and examine time trends overall and by key characteristics. We included all valid height and weight measurements of kindergarten through 8th grade public school students aged 5 to 15 from school years 2011-12 through 2019-20 (N = 1,370,890 unique students; 5,254,058 observations). Obesity and severe obesity were determined using age- and sex-specific body mass index percentiles based on the Centers for Disease Control and Prevention growth charts. Analyses were performed using multivariate logistic regression models with repeated cross-sectional observations weighted to represent the student population for each year and clustered by student and school. Among youth attending public elementary and middle schools in NYC, we estimate that 20.9% and 6.4% had obesity and severe obesity, respectively, in 2019-20. While consistent declines in prevalence were observed overall from 2011-12 to 2019-20 (2.8% relative decrease in obesity and 0.2% in severe obesity, p<0.001), increasing trends were observed among Black, Hispanic, and foreign-born students, suggesting widening disparities. Extending previous work reporting prevalence estimates in this population, nearly all groups experienced significant increases in obesity and severe obesity from 2016-17 to 2019-20 (relative change = 3.5% and 6.7%, respectively, overall; p<0.001). Yet, some of the largest increases in obesity were observed among those already bearing the greatest burden, such as Black and Hispanic students and youth living in poverty. These findings highlight the need for greater implementation of equity-centered obesity prevention efforts. Future research should consider the influence of the COVID-19 pandemic and changes in clinical guidance on childhood obesity and severe obesity in NYC.

Longitudinal associations of screen time, physical activity, and sleep duration with body mass index in U.S. youth

BACKGROUND

Youth use different forms of screen time (e.g., streaming, gaming) that may be related to body mass index (BMI). Screen time is non-independent from other behaviors, including physical activity and sleep duration. Statistical approaches such as isotemporal substitution or compositional data analysis (CoDA) can model associations between these non-independent behaviors and health outcomes. Few studies have examined different types of screen time, physical activity, and sleep duration simultaneously in relation to BMI.

METHODS

Data were baseline (2017-2018) and one-year follow-up (2018-2019) from the Adolescent Brain Cognitive Development Study, a multi-site study of a nationally representative sample of U.S. youth (N = 10,544, mean [SE] baseline age = 9.9 [0.03] years, 48.9% female, 45.4% non-White). Participants reported daily minutes of screen time (streaming, gaming, socializing), physical activity, and sleep. Sex-stratified models estimated the association between baseline behaviors and follow-up BMI z-score, controlling for demographic characteristics, internalizing symptoms, and BMI z-score at baseline.

RESULTS

In females, isotemporal substitution models estimated that replacing 30 min of socializing (β [95% CI] = -0.03 [-0.05, -0.002]), streaming (-0.03 [-0.05, -0.01]), or gaming (-0.03 [-0.06, -0.01]) with 30 min of physical activity was associated with a lower follow-up BMI z-score. In males, replacing 30 min of socializing (-0.03 [-0.05, -0.01]), streaming (-0.02 [-0.03, -0.01]), or gaming (-0.02 [-0.03, -0.01]) with 30 min of sleep was associated with a lower follow-up BMI z-score. In males, replacing 30 min of socializing with 30 min of gaming was associated with a lower follow-up BMI z-score (-0.01 [-0.03, -0.0001]). CoDA estimated that in males, a greater proportion of time spent in baseline socializing, relative to the remaining behaviors, was associated with a higher follow-up BMI z-score (0.05 [0.02, 0.08]). In females, no associations between screen time and BMI were observed using CoDA.

CONCLUSIONS

One-year longitudinal associations between screen time and BMI may depend on form of screen time, what behavior it replaces (physical activity or sleep), and participant sex. The alternative statistical approaches yielded somewhat different results. Experimental manipulation of screen time and investigation of biopsychosocial mechanisms underlying the observed sex differences will allow for causal inference and can inform interventions.

Development of a Fitness Surveillance System to Track and Evaluate Obesity in North Idaho

BACKGROUND

Internationally 18% of youth are obese. Fitness testing can be used to establish fitness surveillance, which can inform policy and targeted interventions aimed at addressing obesity. The purpose of this study was to estimate the prevalence of overweight, obesity, and low fitness in Idaho school-aged youth through a pilot study.

METHODS

A convenience sample of 13 teachers from 11 north Idaho rural schools collected FitnessGram fitness data: body composition (body mass index [BMI]), aerobic capacity (Progressive Aerobic Cardiovascular Endurance Run [PACER] test), muscular endurance (curl up), strength (pushup), and flexibility (sit and reach).

RESULTS

A total of 761 students (aged 9-18 years) from grades 3&5, 7, and 9 to 12 participated in the study. Approximately 24% of 3&5 and 22% of 7th, and 12% of 9 to 12th-grade students were categorized as Needs Improvement/Health Risk by FitnessGram standards for BMI. Similarly, approximately 25% of 3&5, and 22% of 7 and 9 to 12th-grade students were considered Needs Improvement/Health Risk for PACER.

IMPLICATIONS FOR SCHOOL HEALTH POLICY, PRACTICE, AND EQUITY

Results from fitness testing can provide school and public health representatives with a "needs assessment" of student health that can be used to help develop policies and practices to improve student health and wellbeing.

CONCLUSIONS

This study provides a model for statewide annual fitness testing surveillance and reporting within K-12 public school physical education classrooms.

Relative Body Mass Index Improves the BMI Percentile Performance for Detection and Monitoring of Excess Adiposity in Adolescents

Obesity is defined as excess adipose tissue; however, commonly used methods may under-detect adiposity in adolescents. This study compared the performance of body mass index percentile (BMI%) and relative body mass index (RBMI) in identifying excess body fat percentage (BF%) and estimated RBMI cut points to better stratify severity of adiposity. In 567 adolescents ages 11-19 year, BF% measured by DXA was used to compare BMI% and RBMI performance at different degrees of adiposity. RBMI cut points for adiposity detection were derived via ROC curve analysis. BF% was strongly correlated with BMI% (r = 0.889, p < 0.001) and RBMI (r = 0.901, p < 0.001). However, RBMI exhibited less dispersion and better discriminated the relationship with BF% independent of age, race, and gender. Both BMI% and RBMI performed similarly for detecting high BF% (≥25 BF% in males; ≥30 BF% in females). Nonetheless, the relationship of BMI% with BF% was diminished among leaner adolescents. RBMI detected overweight in 21.3% more females and 14.2% more males. RBMI improved the detection of excess adiposity in individuals otherwise classified as having normal weight or overweight by BMI%. RBMI is a valuable and accessible tool for earlier detection, intervention, and effective follow-up of excess adiposity in youth at higher risk for complications.

Sex differences in a mouse model of diet-induced obesity: the role of the gut microbiome

BACKGROUND

Recent decades have seen an exponential rise in global obesity prevalence, with rates nearly doubling in a span of 40 years. A comprehensive knowledge base regarding the systemic effects of obesity is required to create new preventative and therapeutic agents effective at combating the current obesity epidemic. Previous studies of diet-induced obesity utilizing mouse models have demonstrated a difference in bodyweight gain by sex. In such studies, female mice gained significantly less weight than male mice when given the same high fat (HF) diet, indicating a resistance to diet-induced obesity. Research has also shown sex differences in gut microbiome composition between males and females, indicated to be in part a result of sex hormones. Understanding metabolic differences between sexes could assist in the development of new measures for obesity prevention and treatment. This study aimed to characterize sex differences in weight gain, plasma lipid profiles, fecal microbiota composition, and fecal short chain fatty acid levels. We hypothesized a role for the gut microbiome in these sex differences that would be normalized following microbiome depletion.

METHODS

A mouse model was used to study these effects. Mice were divided into treatment groups by sex, diet, and presence/absence of an antibiotic cocktail to deplete genera in the gut microbiome. We hypothesized that sex differences would be present both in bodyweight gain and systemic measures of obesity, including hormone and circulating free fatty acid levels.

RESULTS

We determined statistically significant differences for sex and/or treatment for the outcome measures. We confirm previous findings in which male mice gained significantly more weight than female mice fed the same high fat diet. However, sex differences persisted following antibiotic administration for microbiome depletion.

CONCLUSIONS

We conclude that sex differences in the gut microbiome may contribute to sex differences in obesity, but they do not explain all of the differences.

Sex differences in a mouse model of diet-induced obesity: the role of the gut microbiome

Background

Recent decades have seen an exponential rise in global obesity prevalence, with rates nearly doubling in a span of forty years. A comprehensive knowledge base regarding the systemic effects of obesity is required to create new preventative and therapeutic agents effective at combating the current obesity epidemic. Previous studies of diet-induced obesity utilizing mouse models have demonstrated a difference in bodyweight gain by sex. In such studies, female mice gained significantly less weight than male mice when given the same high fat (HF) diet, indicating a resistance to diet-induced obesity. Research has also shown sex differences in gut microbiome composition between males and females, indicated to be in part a result of sex hormones. Understanding metabolic differences between sexes could assist in the development of new measures for obesity prevention and treatment. This study aimed to characterize sex differences in weight gain, plasma lipid profiles, fecal microbiota composition, and fecal short chain fatty acid levels. We hypothesized a role for the gut microbiome in these sex differences that would be normalized following microbiome depletion.

Methods

A mouse model was used to study these effects. Mice were divided into treatment groups by sex, diet, and presence/absence of an antibiotic cocktail to deplete genera in the gut microbiome. We hypothesized that sex differences would be present both in bodyweight gain and systemic measures of obesity, including hormone and circulating free fatty acid levels.

Results

We determined statistically significant differences for sex and/or treatment for the outcome measures. We confirm previous findings in which male mice gained significantly more weight than female mice fed the same high fat diet. However, sex differences persisted following antibiotic administration for microbiome depletion.

Conclusions

We conclude that sex differences in the gut microbiome may contribute to sex differences in obesity, but they do not explain all of the differences.

Multilevel prenatal socioeconomic predictors of Mexican American children's cardiometabolic health in preschool and school age

OBJECTIVE

Using a life course perspective, this longitudinal study examines the extent to which prenatal family- and neighborhood-level socioeconomic factors influence the cardiometabolic health of low-income Mexican American children. It was hypothesized that prenatal maternal residence in a more economically disadvantaged neighborhood and more family-level economic hardship would each be associated with higher adiposity and blood pressure (BP) at child age 4.5 years, and higher adiposity, BP, inflammation and a less healthy lipid profile at child age 7.5 years.

METHOD

The sample consisted of 322 low-income, Mexican American mother-child dyads, 181 of whom completed the 7.5-year laboratory visit. Using maternal prenatal residence and U.S. census data, neighborhood concentrated disadvantage index was computed.

RESULTS

Higher prenatal neighborhood concentrated disadvantage predicted higher 4.5-year adiposity in children, which, in turn, predicted higher adiposity, BP, and inflammation, and less healthy lipid profile (higher triglycerides, lower high-density lipoprotein cholesterol) at 7.5 years. Higher child 4.5-year BP was concurrently associated with higher adiposity and predicted higher 7.5-year BP.

CONCLUSIONS

Extending previous work with this sample, the current study found associations between cardiometabolic risk indicators as early as preschool among Mexican American children. Furthermore, this study builds on existing literature by expanding our understanding of the effect of prenatal neighborhood concentrated disadvantage on cardiometabolic phenotypes during early childhood. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Electronic phenotypes to distinguish clinician attention to high body mass index, hypertension, lipid disorders, fatty liver and diabetes in pediatric primary care: Diagnostic accuracy of electronic phenotypes compared to masked comprehensive chart review

BACKGROUND/OBJECTIVES

Electronic phenotyping is a method of using electronic-health-record (EHR) data to automate identifying a patient/population with a characteristic of interest. This study determines validity of using EHR data of children with overweight/obesity to electronically phenotype evidence of clinician 'attention' to high body mass index (BMI) and each of four distinct comorbidities.

METHODS

We built five electronic phenotypes classifying 2-18-year-old children with overweight/obesity (n = 17,397) by electronic/health-record evidence of distinct attention to high body mass index, hypertension, lipid disorders, fatty liver, and prediabetes/diabetes. We reviewed, selected and cross-checked random charts to define items clinicians select in EHRs to build problem lists, and to order medications, laboratory tests and referrals to electronically classify attention to overweight/obesity and each comorbidity. Operating characteristics of each clinician-attention phenotype were determined by comparing comprehensive chart review by reviewers masked to electronic classification who adjudicated evidence of clinician attention to high BMI and each comorbidity.

RESULTS

In a random sample of 817 visit-records reviewed/coded, specificity of each electronic phenotype is 99%-100% (with PPVs ranging from 96.8% for prediabetes/diabetes to 100% for dyslipidemia and hypertension). Sensitivities of the attention classifications range from 69% for hypertension (NPV, 98.9%) to 84.7% for high-BMI attention (NPV, 92.3%).

CONCLUSIONS

Electronic phenotypes for clinician attention to overweight/obesity and distinct comorbidities are highly specific, with moderate (BMI) to modest (each comorbidity) sensitivity. The high specificity supports using phenotypes to identify children with prior high-BMI/comorbidity attention.

Differential associations between television viewing, computer use, and adiposity by age, gender, and race/ethnicity in United States youth: A cross-sectional NHANES analysis

BACKGROUND

Time spent on screens and adiposity change rapidly from childhood to adolescence, with differences by gender and race/ethnicity.

OBJECTIVE

Apply time-varying effect models (TVEMs) to a nationally representative sample of youth to identify the age ranges when the cross-sectional associations between television viewing, computer use, and adiposity are significant.

METHODS

Data from 8 to 15-year-olds (n = 3593) from the National Health and Nutrition Examination Survey (2011-2018) were extracted. TVEMs estimated the associations between television viewing, computer use, and fat mass index as dynamic functions of the participants' age, stratified by gender and race/ethnicity.

RESULTS

TVEMs revealed age-specific statistically significant associations that differed by gender and race/ethnicity. Notably, computer use was related to higher adiposity in non-Hispanic White females aged 9.3-11.4 years (slope β-range: 0.1-0.2) and in non-Hispanic Black females older than 14.8 years (β-range: 0.1-0.5). In males, these age windows were 13.5-15.0 years (non-Hispanic White, β-range: 0.1-0.2), 11.4-13.0 years (non-Hispanic Black, β-range: 0.1-0.14), and older than 13.0 years (Hispanic, β-range: 0.1-0.4).

CONCLUSIONS

More research during the specific age ranges in the demographic subgroups identified here could increase our understanding of tailored interventions in youth.

Changing epidemiology, global trends and implications for outcomes of NAFLD

Non-alcoholic fatty liver disease (NAFLD) has rapidly become the most common liver disease globally and is currently estimated to affect 38% of the global population. Only a minority of patients with NAFLD will progress to cirrhosis or hepatocellular carcinoma, but from this vast population the total number of patients who are at risk of such severe outcomes is increasing. Worryingly, individuals are increasingly being affected by NAFLD at an earlier age, meaning there is more time for them to develop severe complications. With considerable changes in dietary composition and urbanisation, alongside the growth in obesity and type 2 diabetes in the global population, in particular in developing countries, the global proportion of persons affected by NAFLD is projected to increase further. Yet, there are large geographical discrepancies in the prevalence rates of NAFLD and its inflammatory component non-alcoholic steatohepatitis (NASH). Such differences are partly related to differing socio-economic milieus, but also to genetic predisposition. In this narrative review, we discuss recent changes in the epidemiology of NAFLD and NASH from regional and global perspectives, as well as in special populations. We also discuss the potential consequences of these changes on hepatic and extrahepatic events.

Associations of food reinforcement and food- related inhibitory control with adiposity and weight gain in children and adolescents

Some, but not all studies have reported that, among youth with disordered eating and high weight, the relative reinforcing value of food (RRV-F, i.e., how hard a person will work for a high-energy-dense food when another reward is available) is greater, and food-related inhibitory control (i.e., ability to withhold a response to food-related stimuli) is lower, compared to peers without disordered eating or overweight. In most studies, high RRV-F and low food-related inhibitory control have been studied separately, as independent factors, with each suggested to predict excess weight and adiposity (fat mass) gain. We hypothesized that the interaction of these factors would prospectively exacerbate risk for weight and adiposity (fat mass) gain three years later in a sample of healthy youth. At baseline, RRV-F was measured using a Behavior Choice Task with the rewards being standardized servings of chocolate candies, cheese crackers, or fruit snacks. Food-related inhibitory control was determined by performance in response to food and non-food stimuli during a Food Go/No-Go task. At baseline and 3-year visits, total body adiposity was measured by dual-energy X-ray absorptiometry (DXA) and body mass index (BMI) was obtained using measured weight and height. A linear regression was conducted with 3-year adiposity as the dependent variable. RRV-F, food-related inhibitory control, and the RRV-F x food-related inhibitory control interaction as independent variables. Baseline adiposity, age, height, sex, race/ethnicity, and days between visits were included as covariates for model predicting 3-year adiposity. Baseline BMI, age, sex, race/ethnicity, and days between visits were included as covariates for model predicting 3-year BMI. One-hundred and nine youth (mean 12.4±2.7y, mean 0.50±1.02 BMIz, 30.3% with overweight/obesity, 45.9% female, 51.4% non-Hispanic White), 8-17 years at baseline, were studied. Baseline food-related inhibitory control (βunstandardized = 0.33, p = .037, 95% CI [.02, 0.64]), but not baseline RRV-F (βunstandardized = -0.003, p = .914), 95% CI [-0.05, 0.05]) was significantly associated with 3-year adiposity such that those with the poorest food-related inhibitory control (great number of commision errors) had the greatest adiposity gain. The interaction between RRV-F and food-related inhibitory control did not predict 3-year adiposity (βunstandardized = -0.07, p = .648, 95% CI [-0.39, 0.25]). The pattern of findings was the same for models examining non-food related inhibitory control. Neither baseline food-related inhibitory control (βunstandardized = 2.16, p = .256, 95% CI [-1.59, 5.92]), baseline RRV-F (βunstandardized = 0.14, p = .660, 95% CI [-0.48, 0.75]), nor their interaction (βunstandardized = -1.18, p = .547, 95% CI [-5.04, 2.69]) were significantly associated with 3-year BMI. However, non-food related inhibitory control (βunstandardized = 0.54, p = .038, 95% CI [.22, 7.15]) was significantly associated with 3-year BMI. In summary, food-related inhibitory control but not RRV-F, was associated with changes in adiposity in a sample of children and adolescents. Among generally healthy youth, food-related inhibitory control may be a more relevant risk factor than food reinforcement for adiposity gain. Additional data are needed to determine how inhibitory control and reward systems, as well as other disinhibited eating behaviors/traits, may interact to promote excess weight gain over time in youth.

Higher body mass index after intrapartum antibiotic exposure in children persists over 10-years

Exposure to intrapartum antibiotic prophylaxis to reduce perinatal group B streptococcal disease was associated with increased childhood body mass index (BMI) persisting to age 10 years compared to no exposure (Δ BMI at 10 years: vaginal delivery 0.14 kg/m2 , caesarean 0.40 kg/m2 ).

Disparities in weight changes during the COVID-19 pandemic-related lockdown in youths

OBJECTIVE

This study evaluates whether changes in weight among school-aged youth in California due to the COVID-19 lockdown vary by social constructs of race/ethnicity and associated social factors.

METHODS

Including 160,472 youth aged 5 to 17 years enrolled at Kaiser Permanente Southern California, mixed effects models stratified by age group were fitted to estimate changes in distance from the median BMI-for-age from March 2020 to January 2021 (lockdown) compared with the same period before the pandemic.

RESULTS

Excess pandemic weight gain was higher among Black and Hispanic youth aged 5 to 17 years than among White and Asian youth; this difference was most pronounced in those aged 5 to 11 years. In youth aged 5 to 11 years, the distance from the median BMI-for-age increased by 1.72 kg/m2 (95% CI: 1.61-1.84) in Hispanic and 1.70 kg/m2 (95% CI: 1.47-1.94) in Black youth during the lockdown compared with 1.16 kg/m2 (95% CI: 1.02-1.29) in non-Hispanic White youth. The excess weight gain was also higher in youth with fewer neighborhood parks and those with state-subsidized health insurance.

CONCLUSIONS

The COVID-19 pandemic lockdown led to a gain of excess body weight, particularly for Black and Hispanic youth; this weight gain varied by social factors associated with race and ethnicity.

Interpersonal and Environmental Protective Factors and Their Associations With Children's Weight Status

Both external structure (ie, participating in extracurricular activities) and family factors (ie, parental emotional support) have separately been linked with children's physical health and well-being, however, their combined effects are less well known. The current study examined the longitudinal associations between participating in structured out-of-school activities and parent reports of warmth/emotional support with children's weight status (ie, zBMI) over time. Utilizing longitudinal data from the United States-based Early Childhood Longitudinal Study, Kindergarten Class of 2010 to 2011 (ECLS-K:2011), we employed a confirmatory factor analysis (CFA) and a latent variable cross-lagged path analysis to examine if emotional supportiveness and participation in structured activities predicted lower zBMI over the course of 1 year. The final sample included 18 135 participants. Mean age of the participants was 8.12 years (±0.38 years), and 51% of children were male. Mean zBMI was 0.54 (±1.12). Structure at baseline predicted increased zBMI in year 2 (β = .03, P = .02) but did not predict parent emotional supportiveness at year 2 (β = -.05, P = .09). Parent emotional supportiveness at baseline predicted greater zBMI at year 2 (β = .02, P = <.01) but did not predict structure at year 2 (β = .02, P = .39). zBMI at baseline did not predict structure (β = .02, P = .25) or parent emotional supportiveness at year 2 (β = -.01, P = .55). Our findings were inconsistent with our hypothesis with regard to directionality. Continued refinement about the role of internal structure (ie, family, and parenting practices) may inform public health prevention strategies to support the well-being of children and families.

Intake of ultra-processed foods and asthenozoospermia odds: A hospital-based case-control study

Background

The intake of ultra-processed foods (UPFs) has increased rapidly in recent years. Evidence has suggested that UPFs has adverse effects on several health outcomes. This study aimed to first evaluate the association between the intake of UPFs and asthenozoospermia odds.

Methods

A hospital-based case-control study including 549 cases and 581 controls was performed in the infertility clinics of Shengjing Hospital of China Medical University from June 2020 to December 2020. Dietary intake was assessed using a validated food frequency questionnaire. Food items were categorized by the NOVA classification system based on the degree of processing. Semen parameters were analyzed according to the World Health Organization guidelines.

Results

The highest tertile of UPFs intake (% of total energy intake) was positively associated with the odds of asthenozoospermia (odds ratio [OR] = 1.53; 95% confidence interval [CI]: 1.12, 2.10; P for trend < 0.05), compared with the lowest tertile. Similar patterns were also found in subgroup analyses among participants with age ≥32 years (OR = 1.58; 95% CI: 1.04, 2.40), BMI ≥ 24 kg/m² (OR = 1.52; 95% CI: 1.04, 2.22), ever cigarette smoking (OR = 1.78; 95% CI: 1.14, 2.79), and ever alcohol drinking (OR = 1.65; 95% CI: 1.01, 2.72), and in sensitivity analyses by using absolute amount (g/day) to calculate the intake of UPFs.

Conclusion

Higher consumption of UPFs was positively associated with the odds of asthenozoospermia. More studies are needed to confirm our findings.

Transient Elastography Measures of Hepatic Steatosis and Fibrosis Are Associated With Body Composition Among US Adolescents

OBJECTIVES

Obesity-related fatty liver disease impacts long-term adolescent liver health. We examined transient elastography assessed hepatic steatosis and fibrosis distributions and relationships with body composition and lifestyle factors in a United States national adolescent population sample.

METHODS

Liver stiffness and controlled attenuation parameter (CAP) were assessed on 1080 non-Hispanic white, non-Hispanic black, non-Hispanic Asian, and Hispanic boys and girls aged 12-19 years in the National Health and Nutrition Examination Survey (NHANES) 2017-2018. Participants underwent anthropometry and dual-energy x-ray absorptiometry (DXA).

RESULTS

Compared with girls, boys had higher mean CAP (223.7 dB/m vs 215.3 dB/m) and liver stiffness (5.1 kPa vs 4.9 kPa). CAP and liver stiffness increased markedly with body mass index (BMI). In multivariable-adjusted analysis, CAP in the upper quartile was associated with Hispanic and non-Hispanic Asian ethnicity and increased BMI, waist-to-hip ratio, systolic blood pressure, and sedentary time, and decreased physical activity and Healthy Eating Index-2015 score. In multivariable-adjusted analysis, liver stiffness in the upper quartile was associated with male sex, non-Hispanic black ethnicity, and increased BMI, alanine aminotransferase, CAP, and serum cotinine. DXA total percent fat and trunk fat percent were positively related to CAP ( P < 0.001 for each), but not to liver stiffness with multivariable adjustment. Results were similar with CAP and liver stiffness as continuous characteristics.

CONCLUSIONS

In US adolescents, increased anthropometric and DXA body composition measures and lifestyle factors were associated with higher CAP and liver stiffness. Transient elastography and similar noninvasive markers may be utilized for early detection of liver disease in high-risk pediatric populations.

Household income and maternal education in early childhood and risk of overweight and obesity in late childhood: Findings from seven birth cohort studies in six high-income countries

BACKGROUND/OBJECTIVES

This study analysed the relationship between early childhood socioeconomic status (SES) measured by maternal education and household income and the subsequent development of childhood overweight and obesity.

SUBJECTS/METHODS

Data from seven population-representative prospective child cohorts in six high-income countries: United Kingdom, Australia, the Netherlands, Canada (one national cohort and one from the province of Quebec), USA, Sweden. Children were included at birth or within the first 2 years of life. Pooled estimates relate to a total of N = 26,565 included children. Overweight and obesity were defined using International Obesity Task Force (IOTF) cut-offs and measured in late childhood (8-11 years). Risk ratios (RRs) and pooled risk estimates were adjusted for potential confounders (maternal age, ethnicity, child sex). Slope Indexes of Inequality (SII) were estimated to quantify absolute inequality for maternal education and household income.

RESULTS

Prevalence ranged from 15.0% overweight and 2.4% obese in the Swedish cohort to 37.6% overweight and 15.8% obese in the US cohort. Overall, across cohorts, social gradients were observed for risk of obesity for both low maternal education (pooled RR: 2.99, 95% CI: 2.07, 4.31) and low household income (pooled RR: 2.69, 95% CI: 1.68, 4.30); between-cohort heterogeneity ranged from negligible to moderate (p: 0.300 to < 0.001). The association between RRs of obesity by income was lowest in Sweden than in other cohorts.

CONCLUSIONS

There was a social gradient by maternal education on the risk of childhood obesity in all included cohorts. The SES associations measured by income were more heterogeneous and differed between Sweden versus the other national cohorts; these findings may be attributable to policy differences, including preschool policies, maternity leave, a ban on advertising to children, and universal free school meals.

Trends in BMI Percentile and Body Fat Percentage in Children 12 to 17 Years of Age

This study evaluates the cross-sectional trends in body fat percentage (BF%) and body mass index (BMI) percentile rank, and the relationship between the two in 332 (177 boys, 155 girls) 12- to 17-year-old children. Body mass index (BMI) was calculated using measured height and body mass, and sex-specific BMI for age percentile rank was determined using CDC growth charts. Body fat percentage (BF%) was measured with DEXA. Fat mass index (FMI) and fat-free mass index (FFMI) were calculated by normalizing the fat mass and fat-free mass for height. Compared to boys of the same age, girls had significantly higher BF% and FMI values and lower FFMI values. Compared to boys, at a given BMI percentile rank, females had a higher BF% and FMI, and a lower FFMI. In both boys and girls, there was an exponential increase in adiposity above the 70th percentile rank. BMI percentile rank is not an equivalent indicator of body fatness in boys and girls. Other measures of body composition can further inform the practitioner of a child’s adiposity.

Visceral, subcutaneous, and total fat mass accumulation in a prospective cohort of adolescents

BACKGROUND

Race and sex differences in adolescents' body fat are demonstrated in cross-sectional cohorts, yet a longitudinal design would better identify patterns of fat distribution over time.

OBJECTIVES

The aim was to examine race and sex differences in adiposity between black and white adolescents over 2 y.

METHODS

A cohort of adolescents aged 10-16 y (38% black; 52% girls; 15% overweight, 34% with obesity) underwent body composition measurements at baseline (n = 309) and 2 y later (n = 236), using DXA to quantify whole-body fat mass (FM) and MRI for abdominal subcutaneous (SAT) and visceral adipose tissue (VAT) volumes. General linear models were used to examine race and sex differences in log-transformed FM, SAT, and VAT, adjusting for age, sexual maturation, extended BMI percentile, and race-by-sex interaction. SAT and VAT models in addition controlled for baseline FM and change in FM (for change models).

RESULTS

Mean (95% CI) baseline FM (kg) was higher among white [18.5 (17.9, 19.2) than among black adolescents [17.4 (16.6, 18.2), P = 0.03] and girls [19.5 (18.8, 20.3) than boys [16.5 (15.8, 17.2), P < 0.0001]. Mean (95% CI) baseline SAT (L) was higher among girls [4.4 (4.2, 4.6)] than among boys [3.9 (3.7, 4.1), P < 0.0001]. Mean (95% CI) baseline VAT (L) was higher among white [0.5 (0.5, 0.6)] than among black [0.3 (0.3, 0.4)] adolescents (P < 0.0001) and boys [0.5 (0.4, 0.5)] than girls [0.4 (0.4, 0.4), P = 0.04]. Over 2 y mean (95% CI) FM change (kg) was higher among white [3.7 (2.9, 4.5)] than among black adolescents [2.3 (1.3, 3.3), P = 0.04] and girls [4.0 (3.0, 4.9)] than boys [2.0 (1.1, 3.0), P = 0.007], but SAT change (L) did not differ by race or sex. VAT change (L) was higher among white [0.1 (0.1, 0.1)] than among black adolescents [0.0 (0.0, 0.1), P = 0.003] and boys [0.1 (0.1, 0.1)] than girls [0.0 (0.0, 0.1), P = 0.034].

CONCLUSIONS

Sex and race differences in the deposition and accumulation of excess fat are important considerations for understanding obesity prevalence and obesity-related disease risk among adolescents.This trial was registered at clinicaltrials.gov as NCT02784509.

Visceral adipose tissue and cardiometabolic risk factors in young Hispanic and non-Hispanic girls

BACKGROUND

Risk factors for cardiometabolic diseases (e.g., type 2 diabetes, cardiovascular disease) can begin developing in childhood. Elevated body mass index (BMI) is associated with greater likelihood of developing such diseases; however, this relationship varies by race and ethnicity. Notably, Hispanics tend to have high rates of obesity and are disproportionately affected by type 2 diabetes. We aimed to determine if visceral adiposes tissue (VAT) is associated with cardiometabolic risk factors (i.e., triglycerides, cholesterol, insulin resistance, C-reactive protein, and blood pressure), independent of BMI percentile, in a sample of primarily Hispanic adolescent girls.

METHODS AND RESULTS

A total of 337 girls (73% Hispanic) took part in the cross-sectional study. Hispanic girls generally had greater BMI percentile, VAT, and cardiometabolic risk factors compared to non-Hispanic girls. Multiple linear regression was used to assess the relationships between Dual-energy X-ray Absorptiometry (DXA)-derived VAT and cardiometabolic outcomes, controlling for BMI percentile (<85th percentile or ≥85th percentile), age, ethnicity (Hispanic/non-Hispanic), and Tanner stage. Significant interactions between VAT and BMI percentile were identified for almost all cardiometabolic outcomes. Upon stratification, the association between VAT and cardiometabolic outcomes was strongest in girls ≥85th BMI percentile, as compared to girls <85th percentile. However, VAT was only significantly associated with higher triglycerides (girls ≥85th percentile) and higher insulin resistance (both BMI percentiles) after stratification.

CONCLUSION

VAT was associated with increased triglycerides and insulin resistance in girls with overweight or obesity. These findings warrant further investigation between VAT and cardiometabolic health in Hispanic adolescents who tend to accumulate more adipose tissue during adolescence.

Measuring Skin Carotenoids Using Reflection Spectroscopy in a Low-Income School Setting

Dietary behavior change is difficult to accurately measure in a low-income youth population. Objective tools to measure fruit and vegetable consumption without relying on self-report present the opportunity to do this with less respondent burden and bias. A promising tool for quantifying fruit and vegetable consumption via proxy is skin carotenoids as measured by reflection spectroscopy through a device called the Veggie Meter®. To assess whether the Veggie Meter® is able to detect changes in skin carotenoids as a proxy for fruit and vegetable consumption in a low-income school setting, skin carotenoid measurements were collected at three time points, along with student level demographics, anthropometric measurements, and nutrition knowledge. A secondary goal of this study was to refine the protocol to be used based on researcher observations. Repeated measures analysis of variance with Bonferroni correction for multiple comparisons indicate that there was a significant difference in VM scores over the course of the study (F(2, 68) = 6.63, p = 0.002), with an increase in skin carotenoids from Fall 2018 to Spring 2019 (p = 0.005). This increase was sustained over the summer months when measured in Fall 2019. Changes to the protocol included the addition of a hand cleaning step and using the non-dominant ring finger for data collection. With these refinements, the results demonstrate that the Veggie Meter® is usable as a non-invasive tool for measuring fruit and vegetable consumption in a population that is traditionally difficult to assess.