Pediatric obesity is associated with an altered gut microbiota and discordant shifts in Firmicutes populations

An altered gut microbiota has been linked to obesity in adulthood, although little is known about childhood obesity. The aim of this study was to characterize the composition of the gut microbiota in obese (n = 42) and normal‐weight (n = 36) children aged 6 to 16. Using 16S rRNA gene‐targeted sequencing, we evaluated taxa with differential abundance according to age‐ and sex‐normalized body mass index (BMI z‐score). Obesity was associated with an altered gut microbiota characterized by elevated levels of Firmicutes and depleted levels of Bacteroidetes. Correlation network analysis revealed that the gut microbiota of obese children also had increased correlation density and clustering of operational taxonomic units (OTUs). Members of the Bacteroidetes were generally better predictors of BMI z‐score and obesity than Firmicutes, which was likely due to discordant responses of Firmicutes OTUs. In accordance with these observations, the main metabolites produced by gut bacteria, short chain fatty acids (SCFAs), were higher in obese children, suggesting elevated substrate utilisation. Multiple taxa were correlated with SCFA levels, reinforcing the tight link between the microbiota, SCFAs and obesity. Our results suggest that gut microbiota dysbiosis and elevated fermentation activity may be involved in the etiology of childhood obesity.     

不同身体质量指数人群肠道菌群结构及共存网络解析

[背景] 人体能量稳态失衡表现为体重过轻、超重和肥胖,肠道菌群与人体能量稳态的维持有关,但不同身体质量指数（Body Mass Index,BMI）人群的肠道菌群特征仍需进一步探究。[目的] 基于美国肠道计划公开数据库,解析4类BMI人群肠道菌群的特征,并探究4类BMI人群肠道菌群共存网络特征及差异,为基于肠道菌群来干预肥胖及体重过轻等不健康状态提供新的理论依据。[方法] 从美国肠道计划数据集中筛选具有BMI信息的肠道菌群样本,并根据世界卫生组织规定的BMI划分标准将筛选后的样本分为4类：体重过轻（BMI<18.5 kg/m²）,正常体重（18.5 kg/m²2）,超重（25 kg/m²2）,肥胖（BMI>30 kg/m²）;通过计算和比较肠道菌群的α多样性和β多样性探究4类BMI人群肠道菌群的整体结构特征及差异;通过多元线性回归模型对不同BMI分类与肠道菌群进行相关性分析,并且将地域、年龄、性别因素作为混杂因素加入到模型中进行校正;采用SparCC分别计算4类BMI人群肠道菌群中菌属相关性,并分别构建肠道菌群共存网络。[结果] 经过Wilcoxon秩和检验,发现体重过轻、超重、肥胖人群的肠道菌群α多样性都显著低于正常体重人群;β多样性分析结果表明4类BMI人群肠道菌群的整体结构存在显著差异;4类BMI人群肠道中厚壁菌门（Firmicutes）和拟杆菌门（Bacteroidetes）的相对含量无显著差异;通过MaAsLin分析,并且将地域、年龄、性别因素作为混杂因素加入到模型中进行校正,共得到49个与BMI类型显著相关的物种;4类BMI人群肠道菌群共存网络的拓扑结构具有一定差异,体重过轻和正常体重人群肠道菌群共存网络的复杂度较高,超重和肥胖人群肠道菌群共存网络的复杂度较低。[结论] 4类BMI人群肠道菌群的多样性、整体结构和共存网络间均存在差异。     

Microbiota and SCFA in Lean and Overweight Healthy Subjects

Obesity has recently been linked to the composition of human microbiota and the production of short chain fatty acids (SCFAs). However, these findings rely on experimental studies carried out using rather small and defined groups of volunteers or model animals. Our aim was to evaluate differences within the human intestinal microbiota and fecal SCFA concentration of lean and obese subjects. A total of 98 subjects volunteered to take part in this study. The BMI in kg/m² of 30 volunteers was within the lean range, 35 were overweight and 33 were obese. The fecal microbiota was characterized by real‐time PCR analyses. With the primers used herein we were able to cover 82.3% (interquartile range of 68.3–91.4%) of the total microbiota detectable with a universal primer. In addition, the concentration of SCFA was evaluated. The total amount of SCFA was higher in the obese subject group (P = 0.024) than in the lean subject group. The proportion of individual SCFA changed in favor of propionate in overweight (P = 0.019) and obese subjects (P = 0.028). The most abundant bacterial groups in faeces of lean and obese subjects belonged to the phyla Firmicutes and Bacteroidetes. The ratio of Firmicutes to Bacteroidetes changed in favor of the Bacteroidetes in overweight (P = 0.001) and obese subjects (P = 0.005). Our results are in line with previous reports suggesting that SCFA metabolism might play a considerable role in obesity. However, our results contradict previous reports with regard to the contribution of various bacterial groups to the development of obesity and this issue remains controversial.     

Eating Frequency is Associated With Energy Intake but Not Obesity in Midlife Women

Midlife women tend to gain weight with age, thus increasing risk of chronic disease. The purpose of this study was to examine associations between overweight/obesity and behavioral factors, including eating frequency, in a cross‐sectional national sample of midlife women (n = 1,099) (mean age = 49.7 years, and BMI = 27.7 kg/m²). Eating behaviors and food and nutrient intakes were based on a mailed 1‐day food record. BMI was calculated from self‐reported height and weight, and level of physical activity was assessed by self‐reported questionnaire. After exclusion of low‐energy reporters (32% of sample), eating frequency was not associated with overweight/obesity (P > 0.05) and was not different between BMI groups (normal, 5.21 ± 1.79; overweight, 5.16 ± 1.74; obese, 5.12 ± 1.68, P = 0.769). Adjusted logistic regression showed that eating frequency, snacking frequency, breakfast consumption, eating after 10 pm and consuming meals with children or other adults were not significantly associated with overweight/obesity. Total energy intake increased as eating frequency increased in all BMI groups, however, obese women had greater energy intake compared to normal weight women who consumed the same number of meals and snacks. Intake of fruit and vegetables, whole grains, dietary fiber, dairy, and added sugars also increased as eating frequency increased. While eating frequency was not associated with overweight/obesity, it was associated with energy intake. Thus, addressing total energy intake rather than eating frequency may be more appropriate to prevent weight gain among midlife women.     

The Feet of Overweight and Obese Young Children: Are They Flat or Fat?

Objective: The purpose of this study was to determine whether the flat feet displayed by young obese and overweight children are attributable to the presence of a thicker midfoot plantar fat pad or a lowering of the longitudinal arch relative to that in non‐overweight children. Research Methods and Procedures: Foot anthropometry, an arch index derived from plantar footprints, and midfoot plantar fat pad thickness measured by ultrasound were obtained for 19 overweight/obese preschool children (mean age, 4.3 ± 0.9 years; mean height, 1.07 ± 0.1 m; mean BMI, 18.6 ± 1.2 kg/m²) and 19 non‐overweight children matched for age, height, and sex (mean age, 4.3 ± 0.7 years; mean height, 1.05 ± 0.1 m; mean BMI, 15.7 ± 0.7 kg/m²). Results: Independent t tests revealed no significant between‐subject group differences (p = 0.39) in the thickness of the midfoot plantar fat pad. However, the overweight/obese children had a significantly lower plantar arch height (0.9 ± 0.3 cm) than their non‐overweight counterparts (1.1 ± 0.2 cm; p = 0.04). Discussion: The lower plantar arch height found in the overweight/obese children suggests that the flatter feet characteristic of overweight/obese preschool children may be caused by structural changes in their foot anatomy. It is postulated that these structural changes, which may adversely affect the functional capacity of the medial longitudinal arch, might be exacerbated if excess weight bearing continues throughout childhood and into adulthood.     

Associations between parental and child overweight and obesity

Results of the analysis showed that parents and children overweight/obesity were significantly correlated. The sample includes 318 pairs of mothers and children, and 336 pairs of fathers and children at the age 11.3 +/- 0.4 years in Trogir, Croatia. Child overweight and obesity were defined according to body mass index (BMI) 25 and 30 equivalents (kg/m2). The prevalence of total overweight in girls was 25.6% and among boys was 20.5%. Mother's weight (p = 0.003) and BMI (p = 0.006) were greater in obese than in other groups of children. Overweight/obese children were more often found among overweight/obese mothers (p = 0.009) and fathers (p = 0.039). Correlation between overweight/obese children and their father (odds ratio 3.2, 95% CI 1.5-6.8) was stronger than between overweight/obese children and their mothers (odds ratio 2.2, 95% CI 1.2-3.9). Associations with mothers' and daughters' overweight/obesity were stronger (p = 0.017) than mothers' and sons'(p = 0.12). Correlations between children's BMI and fathers' BMI (r = 0.265, p < 0.0001) and between children's BMI and mothers' BMI (r = 0.173, p = 0.002) were significant. Children whose parents are overweight/obese look for greater attention in future preventive programme.     

Additive Interactions of Maternal Prepregnancy BMI and Breast‐feeding on Childhood Overweight

Objective: To examine the interactions of maternal prepregnancy BMI and breast‐feeding on the risk of overweight among children 2 to 14 years of age. Research Methods and Procedures: The 1996 National Longitudinal Survey of Youth, Child and Young Adult data in the United States were analyzed (n = 2636). The weighted sample represented 51.3% boys, 78.0% whites, 15.0% blacks, and 7.0% Hispanics. Childhood overweight was defined as BMI ≥95th percentile for age and sex. Maternal prepregnancy obesity was determined as BMI ≥30 kg/m². The duration of breast‐feeding was measured as the weeks of age from birth when breast‐feeding ended. Results: After adjusting for potential confounders, children whose mothers were obese before pregnancy were at a greater risk of becoming overweight [adjusted odds ratio (OR), 4.1; 95% confidence interval (CI), 2.6, 6.4] than children whose mothers had normal BMI (<25 kg/m²; p < 0.001 for linear trend). Breast‐feeding for ≥4 months was associated with a lower risk of childhood overweight (OR, 0.6; 95% CI, 0.4, 1.0; p = 0.06 for linear trend). The additive interaction between maternal prepregnancy obesity and lack of breast‐feeding was detected (p < 0.05), such that children whose mothers were obese and who were never breast‐fed had the greatest risk of becoming overweight (OR, 6.1; 95% CI, 2.9, 13.1). Discussion: The combination of maternal prepregnancy obesity and lack of breast‐feeding may be associated with a greater risk of childhood overweight. Special attention may be needed for children with obese mothers and lack of breast‐feeding in developing childhood obesity intervention programs.     

Obesity and Sugar‐sweetened Beverages in African‐American Preschool Children: A Longitudinal Study

A representative sample of 365 low‐income African‐American preschool children aged 3–5 years was studied to determine the association between sugar‐sweetened beverage consumption (soda, fruit drinks, and both combined) and overweight and obesity. Children were examined at a dental clinic in 2002–2003 and again after 2 years. Dietary information was collected using the Block Kids Food Frequency Questionnaire. A BMI score was computed from recorded height and weight. Overweight and obesity were defined by national reference age‐sex specific BMI: those with an age‐sex specific BMI ≥85th, but <95th percentile as overweight and those with BMI ≥95th age‐sex specific percentile as obese. The prevalence of overweight was 12.9% in baseline, and increased to 18.7% after 2 years. The prevalence of obesity increased from 10.3 to 20.4% during the same period. Baseline intake of soda and all sugar‐sweetened beverages were positively associated with baseline BMI z‐scores. After adjusting for covariates, additional intake of fruit drinks and all sugar‐sweetened beverages at baseline showed significantly higher odds of incidence of overweight over 2 years. Among a longitudinal cohort of African‐American preschool children, high consumption of sugar‐sweetened beverages was significantly associated with an increased risk for obesity.     

Insulin Sensitivity as a Mediator of the Relationship Between BMI and Working Memory‐Related Brain Activation

Midlife obesity is associated with cognitive deficits and cerebral atrophy in older age. However, little is known about the early signs of these deleterious brain effects or the physiological mechanisms that underlie them. Functional magnetic resonance imaging (fMRI) allows us to detect early changes in brain response to cognitive challenges while behavioral performance is still intact. Accordingly, we examined the impact of obesity on functional activation during a 2‐Back task in 32 cognitively normal middle‐aged adults, who were classified into normal, overweight, and obese groups according to BMI. Additionally, we examined insulin sensitivity as a potential mediator of the relationship between BMI and brain activation. Insulin sensitivity is of special interest because insulin is strongly associated with both obesity and central nervous system functioning. Group differences in task‐related brain activation were examined in a priori regions of interest (ROIs) using ANOVA. The obese BMI group displayed significantly lower task‐related activation in the right parietal cortex, BA 40/7, (F(2,29) = 5.26, P = 0.011) than the normal (P = 0.016) and overweight (P = 0.047) BMI groups. Linear regression and bootstrapping methods for assessing indirect effects indicated that insulin sensitivity fully mediated the relationship between task‐related activation in the right parietal cortex and BMI ((F(3,28) = 9.03, P = 0.000), β = 0.611, P = 0.001, 95% confidence interval: ?2.548 to ?0.468). In conclusion, obesity in middle age was related to alterations in brain activation during a cognitive challenge and this association appeared to be mediated by insulin sensitivity.     

Central obesity as a risk factor for prostatic hyperplasia

Objective: Obesity‐related metabolic diseases may influence prostatic hyperplasia. This study examined the impact of obesity on prostate volume in men without overt obesity‐related metabolic diseases. Research Methods and Procedures: We recruited 146 men over the age of 40 years who did not have overt obesity‐related diseases, such as diabetes, impaired fasting glucose, hypertension, or dyslipidemia. Transrectal ultrasonography was performed on all subjects. The subjects were divided into three groups according to their BMI: normal (18.5 to 22.9 kg/m²), overweight (23 to 24.9 kg/m²), and obese (≥25 kg/m²), and two groups according to their waist circumference: normal waist (≤90 cm) and central obesity (>90 cm). The classification of the subgroups was based on the Asia‐Pacific criteria of obesity. We compared the prostate volume among subgroups and assessed factors related to prostatic hyperplasia. Results: Mean prostate volume was 18.8 ± 5.0, 21.8 ± 7.2, and 21.8 ± 5.6 mL in the normal, overweight, and obese groups, respectively, and was 20.0 ± 5.9 and 23.7 ± 5.3 mL in the normal waist and central obesity group, respectively. Prostate volume was significantly greater in the obese group than in the normal group (P = 0.03) and in the central obesity group compared with the normal waist group (P = 0.002). Prostate volume was positively correlated with BMI and waist circumference after adjustment for age. After adjusting for confounding factors, central obesity was an independent factor affecting prostatic hyperplasia, which was defined as a prostate volume >20 mL (odds ratio = 3.37, p = 0.037). Relative to men with both low BMI (18.5 to 22.9 kg/m²) and normal waist circumference, those with high BMI (≥25 kg/m²) and central obesity were at significantly increased risk of prostatic hyperplasia (odds ratio = 4.88, p = 0.008). However, those with high BMI (≥25 kg/m²) and normal waist circumference were not at significantly increased risk. Discussion: Prostate volume was greater in the obese and central obesity groups than in the normal group after patients with overt obesity‐related metabolic diseases were excluded. Although both BMI and waist circumference were positively correlated with prostate volume, central obesity was the only independent factor affecting prostate hyperplasia. We suggest that central obesity is an important risk factor for prostatic hyperplasia.     

Correlates of Participation in a Pediatric Primary Care‐Based Obesity Prevention Intervention

The purpose of this study was to examine the correlates of participation in a childhood obesity prevention trial. We sampled parents of children recruited to participate in a randomized controlled trial. Eligible children were 2.0–6.9 years with BMI ≥95th percentile or 85th to <95th percentile if at least one parent was overweight. We attempted contact with parents of children who were potentially eligible. We recruited 475 parents via telephone following an introductory letter. We also interviewed 329 parents who refused participation. Parents who refused participation (n = 329) did not differ from those who participated (n = 475) by number of children at home (OR 0.94 per child; 95% CI: 0.77–1.15) or by child age (OR 1.07 per year; 95% CI: 0.95–1.20) or sex (OR 1.06 for females vs. males; 95% CI: 0.80–1.41). After multivariate adjustment, parents who were college graduates vs. <college graduates were less likely to participate (OR 0.62; 95% CI: 0.46–0.83). In addition, parents were less likely (OR 0.41; 95% CI: 0.31–0.56) to participate if their child was overweight vs. obese. Among the 115 refusers with obese children, 21% cited as a reason for refusal that their children did not have a weight problem, vs. 30% among the 214 refusers with overweight children. In conclusion, parents of preschool‐age children with a BMI 85–95th%ile are less likely to have their children participate in an obesity prevention trial than parents of children with BMI >95th%ile. One reason appears to be that they less frequently consider their children to have a weight problem.     

Ability to taste 6-n-propylthiouracil and BMI in low-income preschool-aged children

Background: Sensitivity to the bitter compound 6‐n‐propylthiouracil (PROP) is genetically mediated. Sensitivity to PROP has been associated with weight status in both adults and children. Objective: To determine whether there is an association between PROP sensitivity and BMI in low‐income children of diverse race/ethnicity, among whom there is a high prevalence of obesity. Methods and Procedures: Eighty‐one preschool‐aged children attending Head Start tasted a solution of 560 μmol/l PROP and reported whether it tasted “like water” or “like something else”. Mothers reported child's race, age, maternal education, maternal weight and height, child's reluctance to sample new foods via the Food Neophobia Scale (FNS), and child's dietary intake using a food frequency questionnaire. Child weight and height were measured. BMI was calculated and for children, expressed in z‐scores. Regression analyses were used to evaluate the relationship between child's PROP taster status and BMI z‐score, testing covariates child's age, gender, race, maternal education and BMI, and child's FNS score. Children's dietary intake was compared by PROP taster status. Results: PROP tasters, compared with nontasters, had significantly higher BMI z‐scores (0.99 (s.d. 1.24) vs. 0.03 (1.12), P = 0.004) and had a significantly higher prevalence of overweight (31.8% vs. 5.6%, P = 0.025), but demonstrated no differences in reported dietary intake. The most parsimonious model predicting the child's BMI z‐score included only maternal BMI and the child's PROP taster status (R ² = 22.3%). Discussion: A genetically mediated ability to taste bitter may contribute to obesity risk in low‐income, preschool‐aged children.     

Development of guidelines for assessing obesity in captive chimpanzees (Pan troglodytes)

Many captive chimpanzees (Pan troglodytes) are subjectively considered to be overweight or obese. However, discussions of obesity in chimpanzees are rare in the literature, despite the acknowledged problem. No study to date has systematically examined obesity in captive chimpanzees. This project develops guidelines for defining obesity in captive chimpanzees through the examination of morphometric and physiologic characteristics in 37 adult female and 22 adult male chimpanzees. During each animal's biannual physical exam, morphometric data was collected including seven skinfolds (mm), body mass index (BMI), waist‐to‐hip ratio (WHR), and total body weight (kg). The morphometric characteristics were correlated with triglycerides and serum glucose concentration, to test the utility of morphometrics in predicting relative obesity in captive chimpanzees. Abdominal skinfold (triglyceride: F=3.83, P=0.05; glucose: F=3.83, P=0.05) and BMI (triglyceride: F=10.42, p=0.003; glucose: F=6.20, P=0.02) were predictive of increased triglycerides and serum glucose in females; however no morphometric characteristics were predictive of relative obesity in males. Results suggest that no males in this population are overweight or obese. For females, there were additional significant differences in morphometric (skinfolds, BMI, WHR, total body weight) and physiologic measurements (systolic and diastolic blood pressure, red blood cells) between individuals classified overweight and those classified non‐overweight. Skinfold measurements, particularly abdominal, seem to be an accurate measure of obesity and thus potential cardiovascular risk in female chimpanzees, but not males. By establishing a baseline for estimated body fat composition in female captive chimpanzees, institutions can track individuals empirically determined to be obese, as well as obesity‐related health problems. Zoo Biol 0:1–12, 2007. © 2007 Wiley‐Liss, Inc.     

Oxidant Stress in Healthy Normal‐weight,Overweight, and Obese Individuals

This study was undertaken to investigate the association among BMI and lipid hydroperoxide (LH), total antioxidant status (TAS), superoxide dismutase (SOD), and reduced glutathione (GSH). Ninety (n = 90) healthy males and females (n = 23/67) (29 normal weight (BMI: 22.74 ± 0.25 kg/m²), 36 overweight (BMI: 27.18 ± 0.23 kg/m²), and 25 obese (33.78 ± 0.48 kg/m²)) participated in the study. Data collected included anthropometric measures, fasting blood glucose, lipid profile, LH, TAS, and enzymatic antioxidants (SOD, and reduced GSH). The results of the study showed that obese individuals had significantly increased LH levels compared to normal‐weight individuals (obese vs. normal weight (0.88 ± 0.05 vs. 0.67 ± 0.03 µmol/l, P < 0.01)) but the increased levels were not significantly different when compared to the overweight group (obese vs. overweight (0.88 ± 0.05 vs. 0.79 ± 0.05 µmol/l)). No other consistent significant differences in TAS, SOD, and GSH were identified between groups. This study concluded that only obesity and not moderate overweight elevates LH levels. Furthermore, the levels of TAS, SOD, and GSH in obesity do not explain the increased LH levels observed in obesity.     

High childhood obesity in an Australian population

Objective: The objective was to determine the prevalences of overweight and obesity in regional Australian children and to examine the association between BMI and indicators of socioeconomic status (SES). Research Methods and Procedures: Regionally representative cross‐sectional survey of 2184 children, 4 to 12 years of age, was conducted, and the socio‐demographic characteristics of their parents from regional Victoria, Australia, 2003 to 2004, were obtained. Results: The prevalences of overweight and obesity were 19.3 ± 0.8% (proportion ± standard error) and 7.6 ± 0.6%, respectively, using international criteria, and the proportion of overweight/obese girls was significantly higher than that of boys (29.6 ± 1.4% vs. 23.9 ± 1.3%, χ² = 9.01, p = 0.003). Children from households of lower SES had higher odds of being overweight/obese; lower SES was defined by lower paternal education (adjusted odds ratio, 1.18; 95% confidence interval, 1.08 to 1.30) and lower area‐level SES (adjusted odds ratio, 1.13; 95% confidence interval, 1.02 to 1.25), adjusted for age, gender, height, and clustering by school. Discussion: The prevalences of overweight and obesity are increasing in Australian children by about one percentage point per year. This equates to ～40,000 more overweight children each year, placing Australian children among those at highest risk around the world. In addition, girls are more likely to be overweight, and there is a general trend for children of lower SES to be at even greater risk of overweight and obesity.     

Primary antiphospholipid antibody syndrome—one further aspect of thrombophilia in overweight and obese patients with venous thromboembolism

Objective: Overweight and obesity are established risk factors for venous thromboembolism (VTE). We examined the difference in the frequency of primary antiphospholipid antibody syndrome (PAPS) in VTE patients according to their BMI. Design and Methods: We included 998 VTE patients treated at our institution between 2009 and 2011 in a retrospective data analysis. Thrombophilia screening including evaluation for APS (lupus anticoagulant, anti‐cardiolipin, and anti‐B2‐glycoprotein‐I IgG and IgM antibodies) was performed in all patients. Results: PAPS was diagnosed in 6.8% (24/355) of normal weight (BMI < 24 kg/m²) VTE patients, in 11.1% (50/452) of overweight (BMI 25–30 kg/m²) VTE patients, and in 15.7% (30/191) of obese (BMI > 31 kg/m²) VTE patients. The difference of PAPS occurrence between these groups was statistically significant (P = 0.001). PAPS patients demonstrated higher fibrinogen levels as compared to non‐PAPS patients (median 416.0 md/dl vs. 352.0 mg/dl, P = 0.001). Furthermore, fibrinogen levels increased significantly according to the body weight of patients (median normal weight patients 330.0 mg/dl vs. overweight patients 359.0 mg/dl vs. obese patients 415.0 mg/dl, P = 0.001). Conclusion: PAPS seems to be more frequent in overweight and obese patients. As PAPS patients showed significantly higher fibrinogen levels and as fibrinogen levels increased significantly according to the body weight of patients, an elevated inflammatory state in overweight and obese patients as a reason for the increased PAPS occurrence can be assumed.     

Racial Differences in the Tracking of Childhood BMI to Adulthood

Objective: The possibility that there are racial differences in the patterns of BMI (kilograms per meter squared) change throughout life has not been examined. For example, the high prevalence of obesity among black women could result from a higher prevalence of obesity among black girls or because normal‐weight black girls experience larger BMI increases in adolescence or adulthood than do their white counterparts. Therefore, we examined the tracking of childhood BMI into adulthood in a biracial (36% black) sample. Research Methods and Procedures: Five‐ to 14‐year‐old children (2392) were followed for (mean) 17 years. Childhood overweight was defined as BMI ≥ 95th percentile, and adult obesity was defined as BMI ≥ 30 kg/m². Results: The tracking of childhood BMI differed between whites and blacks. Among overweight children, 65% of white girls vs. 84% of black girls became obese adults, and predictive values among boys were 71% (whites) vs. 82% (blacks). These racial differences reflected contrasting patterns in the rate of BMI change. Although the initial BMI of black children was not higher than that of white children, BMI increases with age were larger among black girls and overweight black boys than among their white counterparts. In contrast, relatively thin (BMI < 50th percentile) white boys were more likely to become overweight adults than were their black counterparts. Discussion: These findings emphasize the black/white differences in BMI changes with age. Because of the adult health consequences of childhood‐onset obesity, early prevention should be given additional emphasis.     

Interplay Between Weight Loss and Gut Microbiota Composition in Overweight Adolescents

The aim of this study was to determine the influence of an obesity treatment program on the gut microbiota and body weight of overweight adolescents. Thirty‐six adolescents (13–15 years), classified as overweight according to the International Obesity Task Force BMI criteria, were submitted to a calorie‐restricted diet (10–40%) and increased physical activity (15–23 kcal/kg body weight/week) program over 10 weeks. Gut bacterial groups were analyzed by quantitative real‐time PCR before and after the intervention. A group of subjects (n = 23) experienced >4.0 kg weight loss and showed significant BMI (P = 0.030) and BMI z‐score (P = 0.035) reductions after the intervention, while the other group (n = 13) showed <2.0 kg weight loss. No significant differences in dietary intake were found between both groups. In the whole adolescent population, the intervention led to increased Bacteroides fragilis group (P = 0.001) and Lactobacillus group (P = 0.030) counts, and to decreased Clostridium coccoides group (P = 0.028), Bifidobacterium longum (P = 0.031), and Bifidobacterium adolescentis (P = 0.044) counts. In the high weight–loss group, B. fragilis group and Lactobacillus group counts also increased (P = 0.001 and P = 0.007, respectively), whereas C. coccoides group and B. longum counts decreased (P = 0.001 and P = 0.044, respectively) after the intervention. Total bacteria, B. fragilis group and Clostridium leptum group, and Bifidobacterium catenulatum group counts were significantly higher (P < 0.001–0.036) while levels of C. coccoides group, Lactobacillus group, Bifidobacterium, Bifidobacterium breve, and Bifidobacterium bifidum were significantly lower (P < 0.001–0.008) in the high weight–loss group than in the low weight–loss group before and after the intervention. These findings indicate that calorie restriction and physical activity have an impact on gut microbiota composition related to body weight loss, which also seem to be influenced by the individual's microbiota.     

Overweight,Obesity, and Binge Eating in a Non‐clinical Sample of Five Brazilian Cities

Objective: To investigate the relationship between obesity/overweight and binge eating episodes (BEEs) in a large nonclinical population. Research Methods and Procedures: Consumers at shopping centers in five Brazilian cities (N = 2858) who participated in an overweight prevention program were interviewed and had weight and height measured to calculate BMI. Results: Prevalence of overweight (BMI = 25 to 29.9 kg/m²) was 46.6% for men and 36.6% for women. Obesity (BMI ≥ 30 kg/m²) was about two‐thirds of the prevalence of overweight. BEEs (subjects who binged one or more times per week over the last 3 months) in normal‐weight individuals was 1.4% for men and 3.9% for women, whereas in overweight/obese, these prevalences were 6.5% and 5.5%, respectively (p < 0.01). After adjustment for age, socioeconomic variables, and childhood obesity, those who reported BEEs had an odds ratio of being overweight/obese of 3.31 (95% confidence interval: 1.11 to 9.85) for men and 1.73 (95% confidence interval: 1.05 to 2.84) for women. Discussion: These findings indicate a strong association between episodes of binge eating and overweight/obesity, mainly among men.     

Psychosocial Factors and Health Perceptions in Parents and Children Who Are Overweight or Obese

This study examined the relationships among weight status (BMI), health perceptions, and psychosocial characteristics in children, parents, and parent–child dyads. A convenient sample of 114 parent–child dyads participated. All children were overweight or obese. Parents and children completed questionnaires by self‐report or interview. Questionnaires included the Parenting Stress Index–Short Form (PSI), the Parents' Stage of Change (SOC) Questionnaire, and the Pediatric Quality of Life Inventory (PedsQL). Child's mean age was 10.34 years (s.d. = 1.87), mean BMI was 28.13 kg/m² (s.d. = 5.46), and mean BMI z‐score was 2.17 (s.d. = 0.38). Parent mean age was 37.28 years (s.d. = 12.66) and mean BMI was 34.07 kg/m² (s.d. = 8.18). Most parents (68.5%) reported that they and their children (70.7%) were African American and many (44.3%) reported that they and their children were Hispanic. Significant correlations included: child health perceptions and child BMI (r = 0.309, P < 0.001) and parent perception of weight and parent BMI (r = 0.691, P < 0.001). For parent–child dyads, one correlation approached significance (child health perceptions and parent stage of change (r = ?0.269, P < 0.01). Findings suggest that characteristics of parent–child dyads may be important considerations in the management of childhood obesity.