SDCCAG8 obesity alleles and reduced weight loss after a lifestyle intervention in overweight children and adolescents

Genome-wide association analyses (GWAS) contributed to the detection of a number of single-nucleotide polymorphisms (SNPs) associated with obesity. However, little is known about the impact of the obesity-risk alleles on weight loss-related phenotypes after lifestyle interventions. A recent meta-analysis of GWAS reported five genomic loci near or in the genes FTO, MC4R, TMEM18, SDCCAG8, TNKS/MSRA that were associated with obesity in children and adolescents. Here, we analyzed the effect of the 10 SNPs representative of the five loci on measures of weight loss and cardiometabolic risk after a 1-year lifestyle intervention in 401 children and adolescents (mean age 10.74 years; 55.4% female; mean BMI 27.42 kg/m(2), mean BMI-standard deviation score (SDS) 2.37). For confirmation of one locus genotyping of three intronic SNPs in SDCCAG8 was performed in 626 obese adults who completed the 10-week hypoenergetic diet program. Intronic variants of SDCCAG8, which are associated with early onset obesity, are associated with reduced weight loss after a 1-year lifestyle intervention in overweight children and adolescents even after adjusting for age, sex, baseline measurement, or multiple testing (all P < 10(-6)). However, our results could not be confirmed in 626 obese adults undertaking a hypoenergetic diet intervention.     

Metabolomics reveals determinants of weight loss during lifestyle intervention in obese children

The amount of weight loss in obese children during lifestyle intervention differs strongly between individuals. The metabolic processes underlying this variability are largely unknown. We hypothesize that metabolomics analyses of serum samples might help to identify metabolic predictors of weight loss. In this study, we investigated 80 obese children aged 6–15 years having completed the one-year lifestyle intervention program ‘Obeldicks’, 40 that achieved a substantial reduction of their body mass index standard deviation score (BMI-SDS) during this intervention (defined as BMI-SDS reduction ≥ 0.5), and 40 that did not improve their overweight status (BMI-SDS reduction < 0.1). Anthropometric and clinical parameters were measured and baseline fasting serum samples of all children were analyzed with a mass spectrometry-based metabolomics approach targeting 163 metabolites. Both univariate regression models and a multivariate least absolute shrinkage and selection operator (LASSO) approach identified lower serum concentrations of long-chain unsaturated phosphatidylcholines as well as smaller waist circumference as significant predictors of BMI-SDS reduction during intervention (p-values univariate models: 5.3E?03 to 1.0E?04). A permutation test showed that the LASSO model explained a significant part of BMI-SDS change (p = 4.6E?03). Our results suggest a role of phosphatidylcholine metabolism and abdominal obesity in body weight regulation. These findings might lead to a better understanding of the mechanisms behind the large inter-individual variation in response to lifestyle interventions, which is a prerequisite for the development of individualized intervention programs.     

Rapid screening for potentially relevant polymorphisms in the human fatty acid amide hydrolase gene using Pyrosequencing

INTRODUCTION: Fatty acid amides such as the endocannabinoid anandamide serve as mammalian lipid transmitters in various physiological and pathophysiological processes including inflammation. They are rapidly degraded by the fatty acid amide hydrolase (FAAH). Non-functional FAAH resulted in reduced inflammatory and nociceptive responses. Evidence suggests that human genetic FAAH variants modulate pain and addiction but their clinical role is still poorly known. We therefore developed reliable high-throughput screening assays for FAAH polymorphisms to facilitate research of their clinical role. MATERIALS AND METHODS: Six simplex Pyrosequencing assays were developed for FAAH polymorphisms dbSNP rs932816, rs4141964, rs324420, rs324419, rs2295633 and rs12029329 spanning the whole FAAH gene. They are frequent or have been functionally associated. Assays were established and validated in DNA samples from 350 healthy unrelated Caucasians. RESULTS: In all 350 DNA samples the six FAAH polymorphisms were identified correctly as verified by control samples obtained by conventional sequencing. The observed frequencies of homozygous, heterozygous and non-carriers of the minor alleles were in agreement with the Hardy-Weinberg equilibrium. Minor allelic frequencies were: rs932816G>A=0.26, rs4141964C>T=0.37, rs324420C>A=0.20, rs324419C>T=0.15, rs2295633G>A=0.35 and rs12029329G>C=0.25. SNPs were in high linkage except between rs324419 and rs12029329. One single haploblock was identified, spanning either the whole gene range or excluding rs12029329 in the 3' region, depending on the statistical procedure of haloblock assignment. CONCLUSION: The presently developed Pyrosequencing assays allow for quick and reliable detection of FAAH genotypes and may facilitate investigations of FAAH genetic functional associations.     

Acute changes in dietary omega-3 fatty acid intake lowers soluble interleukin-6 receptor in healthy adult normal weight and overweight males

OBJECTIVE: To determine the effect of a short-term isocaloric exchange of alpha-linolenic acid (ALA, 18:3n3) for linoleic acid (LA, 18:2n6) on fasting levels of soluble interleukin-6 receptor (sIL6R), and soluble tumor necrosis factor-alpha receptors 1 and 2 (sTNFR1 and sTNFR2) in healthy normal weight and overweight/obese adult males. DESIGN: Four-day clinical intervention study with 0.5% or 5% of total energy from ALA. Fasting (10 h) blood samples were obtained on the morning of day 5 in both diet treatments to measure sTNFR1, sTNFR2, and sIL6R. SUBJECTS: Nine normal weight (BMI < 25 kg/m2) and seven overweight (BMI > or = 25 kg/m2) healthy males. RESULTS: Fasting sIL6R decreased significantly from the control (C) diet following four days on the high ALA isocaloric (ISO) diet in normal weight and overweight/obese subjects (normal weight: C = 34.89 +/- 3.17 ng/ml, ISO = 30.91 +/- 2.24 ng/ml, p < 0.05; overweight/obese: C = 38.19 +/- 3.92 ng/ml, ISO = 33.57 +/- 2.47 ng/ml, p , 0.05). The dietary intervention did not have a significant effect on fasting sTNFR1 or sTNFR2. CONCLUSIONS: The results suggest that an isocaloric exchange of ALA for LA can reduce fasting sIL6R concentration by approximately 11% after a four-day dietary intervention in both overweight/obese and normal weight subjects. The data also suggest that longer exposure to a similar diet may have the potential to reduce inflammatory burden and thus lower the risk of both cardiovascular disease as well as diabetes.     

Lifestyle intervention in obese children with variations in the melanocortin 4 receptor gene

Because information on weight changes after lifestyle intervention in children with mutations in the melanocortin 4 receptor (MC4R) gene is scarce, we compared weight changes after lifestyle intervention between children with and without MC4R variations. A group of 514 overweight children (aged 5-16 years), who presented to participate in a 1-year lifestyle intervention based on exercise, behavior, and nutrition therapy were screened for MC4R mutations. For comparison, children with MC4R mutations leading to reduced receptor function (group A) were each of them randomly matched with five children of same age and gender without MC4R mutations (group B). Changes of weight status were analyzed as change of BMI standard deviation scores (BMI-SDSs). Furthermore, 16 children (3.1%) harbored MC4R mutations leading to reduced receptor function, and 17 (3.3%) children carried variations not leading to reduced receptor function. Children with and without MC4R mutations reduced their overweight at the end of intervention to a similar degree (P = 0.318 between groups based on an intention-to-treat analysis). The maintenance of weight loss after intervention among children with MC4R mutations leading to reduced receptor function failed in contrast to children without such mutations (P < 0.001 adjusted for BMI-SDS at baseline, age, and gender in an intention-to-treat analysis). In conclusion, children with MC4R mutations leading to reduced receptor function were able to lose weight in a lifestyle intervention but had much greater difficulties to maintain this weight loss supporting the impact of these mutations on weight status.     

Weight loss and the effect on stature in children during a residential intervention program

Weight loss is generally high in residential weight-loss programs but the effect of a large weight loss on linear growth is not known. We report the weight loss and the influence on linear growth in a large group of children during a residential weight-loss program focusing on nutrition and physical activity. In a longitudinal noncontrolled intervention study of 990 overweight children (540 girls) attending the weight reduction program from 1990 to 2001 for about 11 weeks (age: 10-14 years, mean BMI-standard deviation score (SDS) at enrollment: 2.83) weight and height were measured initially and after end of treatment. Weekly measurements of height and weight were performed on 138 children. The children lost on average 9.4 kg, reduced their BMI by 4.5 kg/m(2) and BMI-SDS by 0.98. In a multiple regression analysis (P < or = 0.001) weight loss was higher in boys than girls (1.7 kg), higher if the weight was higher at admission (-0.192 kg/kg at baseline) and was positively associated with duration of stay (-80 g/day). Initially the boys' BMI-SDS was higher than the girls' BMI-SDS (P < or = 0.05) but after 8 weeks of treatment the boys had lower BMI-SDS than the girls. There was no negative effect on linear growth during the treatment; on the contrary, linear growth accelerated during the stay as the average increase in height was 2.38 cm corresponding to 11.4 cm/year. In conclusion the children lost close to 1 kg/week during the stay without any negative effect on linear growth. The cause of the linear growth acceleration needs further investigation.     

Circulating oxidized LDL and inflammation in extreme pediatric obesity

Oxidative stress and inflammation have not been well-characterized in extreme pediatric obesity. We compared levels of circulating oxidized low-density lipoprotein (oxLDL), C-reactive protein (CRP), and interleukin-6 (IL-6) in extremely obese (EO) children to normal weight (NW) and overweight/obese (OW/OB) children. OxLDL, CRP, IL-6, BMI, blood pressure, and fasting glucose, insulin, and lipids were obtained in 225 children and adolescents (age 13.5 ± 2.5 years; boys 55%). Participants were classified into three groups based on gender- and age-specific BMI percentile: NW (<85th, n = 127), OW/OB (85th- <1.2 times the 95th percentile, n = 64) and EO (≥1.2 times the 95th percentile or BMI ≥35 kg/m(2), n = 34). Measures were compared across groups using analysis of covariance, adjusted for gender, age, and race. Blood pressure, insulin, and lipids worsened across BMI groups (all P < 0.0001). OxLDL (NW: 40.8 ± 9.0 U/l, OW/OB: 45.7 ± 12.1 U/l, EO: 63.5 ± 13.8 U/l) and CRP (NW: 0.5 ± 1.0 mg/l, OW/OB: 1.4 ± 2.9 mg/l, EO: 5.6 ± 4.9 mg/l) increased significantly across BMI groups (all groups differed with P < 0.01). IL-6 was significantly higher in EO (2.0 ± 0.9 pg/ml) compared to OW/OB (1.3 ± 1.2 pg/ml, P < 0.001) and NW (1.1 ± 1.0 pg/ml, P < 0.0001) but was not different between NW and OW/OB. Extreme pediatric obesity, compared to milder forms of adiposity and NW, is associated with higher levels of oxidative stress and inflammation, suggesting that markers of early cardiovascular disease and type 2 diabetes mellitus are already present in this young population.     

RCT of a High‐protein Diet on Hunger Motivation and Weight‐loss in Obese Children: An Extension and Replication

This study aimed to evaluate the weight loss and hunger motivation effects of an energy‐restricted high‐protein (HP) diet in overweight and obese children. In total, 95 overweight and obese children attended an 8‐week (maximum) program of physical activity, reduced‐energy intake, and behavior change education. Children were randomly assigned to one of two isoenergetic diets (standard (SP): 15% protein; HP: 25% protein), based on individually estimated energy requirements. Anthropometry and body composition were assessed at the start and end of the program and appetite and mood ratings completed on the first 3 consecutive weekdays of each week children attended camp. The HP diet had no greater effect on weight loss, body composition, or changes in appetite or mood when compared to the SP diet. Overall, campers lost 5.2 ± 3.0 kg in body weight and reduced their BMI standard deviation score (sds) by 0.25. Ratings of desire to eat increased significantly over the duration of the intervention, irrespective of diet. This is the third time we have reported an increase in hunger motivation in weight‐loss campers and replicates our previous failure to block this with a higher protein diet. Further work is warranted into the management of hunger motivation as a result of negative energy balance.     

Ethnic Differences in Subcutaneous Adiposity and Waist Girth in Children and Adolescents

The purpose of this study was to examine ethnic differences in adiposity as measured by sum of skinfolds (SKF) and waist circumference (WC) in children and adolescents, after statistical adjustment for the BMI and age. A cross sectional sample of 3,218 (55% white, 49% male) children and adolescents aged 5–18 years who participated in the Bogalusa Heart Study (1992–1994) were included in these analyses. Sex‐specific ANOVAs, adjusted for BMI and age, for each 2‐year age group compared measures of adiposity (SKF and WC) between ethnic groups. No significant differences in the proportions of children and adolescents who were overweight and obese by ethnicity or sex were found. Mean SKF in normal weight (P < 0.0001) and overweight (P < 0.0001) categories was higher for white than black children of both sexes. Across most age categories, white boys and girls had significantly higher SKF than black boys and girls, respectively (P ≤ 0.05). Across most age categories, white boys had significantly higher WC than black boys (P ≤ 0.05) with no difference in the girls, when adjusted for BMI and age. Measures of adiposity in childhood and adolescence were significantly higher in white children compared to black children, when adjusted for BMI and age. Throughout childhood and adolescence, white boys and girls had higher SKF and white boys had higher WC. Differences in adiposity between ethnic groups should be considered in disease risk assessment and stratification as they are observed even for a given BMI level.     

Beyond Body Mass Index - Body Composition Assessment by Bioimpedance in Routine Endocrine Practice

ObjectiveTo explore the body composition of pediatric patients referred for endocrine evaluation.MethodsThis real-life observational study conducted between January 2018 and January 2020 included 10 001 clinic visits of 3500 children and adolescents; first visits of 5 to 18-year-old patients were included. Anthropometric data, blood pressure levels, pubertal status, and bioelectrical impedance analysis (BIA, Tanita MC-780 MA) were extracted from medical files. Excluded from the analysis were patients participating in other studies.ResultsA total of 1001 patients (48% boys, mean age 11.3 ± 3.4 years, 33.5% prepubertal) were included. Mean anthropometric z-scores were normal and similar for boys and girls. Sex differences in body composition were as follows: boys had lower fat percentage, lower truncal fat percentage, higher appendicular skeletal muscle mass, and a higher muscle-to-fat ratio (MFR) than girls (P < .001 for all). MFR correlated with body mass index-standard deviation scores (BMI-SDS) in overweight/obese patients (r = −0.558, P < .001), although not in underweight patients. Systolic blood pressure (SBP) correlated with BMI-SDS in overweight/obese patients (r = 0.262, P < .001), although not in underweight patients. Diastolic blood pressure (DBP) did not correlate with BMI-SDS in either group of extreme weight status. MFR correlated with SBP and DBP in overweight/obese patients (r = −0.230, P < .001 and r = −0.141, P = .018, respectively) as well as in underweight patients (r = 0.331, P < .001 and r = 0.264, P = .005, respectively).ConclusionsOur findings support BIA for a more refined characterization of patients referred for endocrine evaluation than BMI-SDS. MFR may be a better surrogate marker of blood pressure levels than BMI-SDS in both underweight and overweight/obese pediatric patients.     

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.     

Evaluation of the association between the AC3 genetic polymorphisms and obesity in a Chinese Han population

Background

AC3 is one of adenylyl cyclase isoforms involved in cAMP and insulin signaling pathway. Recent reports have demonstrated that the AC3 genetic polymorphisms are associated with obesity in a Swedish population. AC3 knock out mice exhibit obese when they age. These findings suggest that AC3 plays an important role in the regulation of body weight.

Methodology/Principal Findings

In the present study, we evaluated the association between the AC3 genetic polymorphisms and obesity in a Han Chinese population. A total of 2580 adults, including 1490 lean (BMI = 18.5–23.9), 677 overweight (BMI 24.0–27.9) and 413 obese (BMI ≥28.0) subjects were genotyped for 5 TagSNPs in the AC3 gene. Single maker association analyses indicated that SNP rs753529 was significantly associated with BMI in obese subjects (P = 0.022, OR = 0.775 95%CI = 0.623–0.963), but not in overweight subjects (P = 0.818). Multiple maker association analyses showed that the haplotype (G-G-G) constructed with SNPs rs1127568, rs7604576 and rs753529 was significantly associated with obesity (P = 0.029). Further genotyping of SNP rs753529 in 816 children, including 361 overweight subjects (BMI>P₈₀) and 455 controls (BMI = P_20–50) were performed, and no significant association with BMI was found. All tests were adjusted for age, sex, physical activity index, household income and/or diet expenses.

Conclusions

The present study provides replication evidence that the AC3 genetic polymorphisms are associated with decreased risk of obesity among adults but not in children in a Chinese Han population. The data also suggest that the AC3 genetic effects on BMI may have interaction with the factors related to ageing and environment.     

Bullying and Victimization in Overweight and Obese Outpatient Children and Adolescents: An Italian Multicentric Study

Objective

Being overweight or obese is one of the most common reasons that children and adolescents are teased at school. We carried out a study in order to investigate: i) the relation between weight status and school bullying and ii) the relation between weight status categories and types of victimization and bullying in an outpatient sample of Italian children and adolescents with different degrees of overweight from minimal overweight up to severe obesity.

Participants/Methods

Nine-hundred-forty-seven outpatient children and adolescents (age range 6.0–14.0 years) were recruited in 14 hospitals distributed over the country of Italy. The participants were classified as normal-weight (N = 129), overweight (N = 126), moderately obese (N = 568), and severely obese (N = 124). The nature and extent of verbal, physical and relational bullying and victimization were assessed with an adapted version of the revised Olweus bully-victim questionnaire. Each participant was coded as bully, victim, bully-victim, or not involved.

Results

Normal-weight and overweight participants were less involved in bullying than obese participants; severely obese males were more involved in the double role of bully and victim. Severely obese children and adolescents suffered not only from verbal victimization but also from physical victimization and exclusion from group activities. Weight status categories were not directly related to bullying behaviour; however severely obese males perpetrated more bullying behaviour compared to severely obese females.

Conclusions

Obesity and bullying among children and adolescents are of ongoing concern worldwide and may be closely related. Common strategies of intervention are needed to cope with these two social health challenges.     

DXA measurements confirm that parental perceptions of elevated adiposity in young children are poor

Objective: To compare parental assessments of child body weight status with BMI measurements and determine whether children who are incorrectly classified differ in body composition from those whose parents correctly rate child weight. Also to ascertain whether children of obese parents differ from those of non‐obese parents in actual or perceived body weight. Research Methods and Procedures: Weights, heights, BMI, and waist girths of New Zealand children ages 3 to 8 years were determined. Fat mass, fat percentage, and lean mass were measured by DXA (n = 96). Parents classified child weight status as underweight, normal‐weight, slightly overweight, or overweight. Centers for Disease Control and Prevention 2000 percentiles of BMI were used. Results: Parents underestimated child weight status. Despite having 83% more fat mass than children with BMI values below the 85th percentile, only 7 of 31 children with BMI values at or above the 85th percentile were rated as slightly overweight or overweight. In the whole sample, participants whose weight status was underestimated by parents (40 of the 96 children) had l9% less fat mass but similar lean mass as children whose weight status was correctly classified. However, children of obese and non‐obese parents did not differ in body composition or anthropometry, and obese parents did not underestimate child weight more than non‐obese parents. Discussion: Because parents underestimate child weight, but BMI values at or above the 85th percentile identify high body fat well, advising parents of the BMI status of their children should improve strategies to prevent excessive fat gain in young children.     

低能量平衡膳食联合有氧运动对单纯性肥胖儿童体脂代谢、胰岛素抵抗及氧化应激反应的影响

摘要 目的：观察单纯性肥胖儿童经有氧运动、低能量平衡膳食联合干预后,机体体脂代谢、胰岛素抵抗及氧化应激反应的变化。方法：选择2019年8月~2021年7月期间新疆医科大学第一附属医院接收的单纯性肥胖儿童93例,将纳入的患儿根据随机数字表法分为对照组和研究组,各为46例和47例。对照组患儿接受低能量平衡膳食干预,研究组患儿接受低能量平衡膳食联合有氧运动干预。对比两组体脂代谢、胰岛素抵抗、血脂及氧化应激反应相关指标变化情况。结果：研究组干预12周后体质量指数（BMI）、甘油三酯（TG）、体脂含量、总胆固醇（TC）、体脂率、腰臀比、空腹胰岛素（FINS）、低密度脂蛋白（LDL-C）、空腹血糖（FPG）、蛋白质羰基（PC）、C肽、胰岛素抵抗指数（HONA-IR）、丙二醛（MDA）低于对照组（P<0.05）。研究组干预12周后高密度脂蛋白（HDL-C）、超氧化物歧化酶（SOD）高于对照组（P<0.05）。结论：低能量平衡膳食联合有氧运动可促进单纯性肥胖儿童体脂代谢改善,减轻胰岛素抵抗及氧化应激反应,效果确切。     

Energy intake, diet composition, energy expenditure, and body fatness of adolescents in northern Greece

Objective: The purpose of this study was to examine energy intake, energy expenditure, diet composition, and obesity of adolescents in Northern Greece. Research Methods and Procedures: Anthropometric measurements were taken for all participants. Height, weight, and skinfold thickness at two sites were measured. BMI and percentage body fat were calculated. Energy intake and macronutrient and micronutrient intakes were determined by a 3‐day weighed dietary diary. Energy expenditure was calculated based on calculated resting metabolic rate (RMR) 1 multiplied by an activity factor based on reported physical activity. Results: Thirty‐one percent of boys and 21% of girls had BMI corresponding to ≥25 kg/m² at 18 years and were classified as overweight. Both overweight boys and girls reported a lower energy intake compared with their non‐overweight counterparts when expressed as kilocalories per kilogram body weight. Overweight children had a higher negative energy balance. Both overweight and non‐overweight adolescents had higher than recommended fat intakes. Mean daily carbohydrate, protein, and fat intake, expressed as grams per kilogram body weight, of overweight adolescents were significantly lower compared with the non‐overweight adolescents. Total daily carbohydrate intake, when expressed in grams, was found to be higher for non‐overweight adolescents. Both overweight boys and girls had lower iron intakes than their non‐overweight counterparts. Overweight boys had statistically lower fiber and niacin intakes than non‐overweight boys. Both overweight and non‐overweight adolescents had lower than recommended iron intakes. Furthermore, overweight adolescents consumed more snacks (potato chips, chocolate bars, pizza, cheese pie, and cream pie), more sugar, jam, and honey, and fewer legumes, vegetables, and fruits than their non‐overweight counterparts. Discussion: Reported energy intake of overweight adolescents was lower than their non‐overweight counterparts. Regarding diet composition overweight subjects had significantly lower intakes of carbohydrates compared with non‐overweight subjects. The food consumption pattern of overweight children showed less adherence to the traditional Mediterranean diet.     

Assessment of copper and lipid profile in obese children and adolescents

The aim of this study was to assess erythrocyte and plasma copper concentrations and correlate them with the lipid profile of overweight and obese children and adolescents. The study was performed with 15 over-weight and 30 obese children and adolescents, and the results were compared to the control group (21), aged 6–16 yr. Anthropometric assessment was carried out using body mass index (BMI). Total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglyceride serum levels were investigated. Erythrocyte and plasma copper levels were determined by atomic absorption spectrophotometry. Greater alterations in the lipid profile were observed in HDL-cholesterol, LDL-cholesterol, and triglyceride levels, with distinctions according to gender. The plasma copper concentrations in the overweight and obese male groups were significantly higher than those in the control group (p=0.0006). Negative correlations between plasma copper and total cholesterol (r=−0.54) and LDL cholesterol (r=−0.59) were observed in the obese male group. There was no statistical difference in copper erythrocyte concentrations. The obesity associated to disorders in lipid metabolism predisposes to changes in copper plasma concentrations, but there was no alteration in intracellular reserves, which suggests an important homeostatic control to compensate for plasma oscillations and metabolic alterations of the disease.     

CETP genotype and changes in lipid levels in response to weight-loss diet intervention in the POUNDS LOST and DIRECT randomized trials

Little is known about whether cholesteryl ester transfer protein (CETP) genetic variation may modify the effect of weight-loss diets varying in fat content on changes in lipid levels. We analyzed the interaction between the CETP variant rs3764261 and dietary interventions on changes in lipid levels among 732 overweight/obese adults from a 2 year randomized weight-loss trial [Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST)], and replicated the findings in 171 overweight/obese adults from an independent 2 year weight-loss trial [Dietary Intervention Randomized Controlled Trial (DIRECT)]. In the POUNDS LOST, participants with the CETP rs3764261 CC genotype on the high-fat diet had larger increases in HDL cholesterol (P = 0.001) and decreases in triglycerides (P = 0.007) than those on the low-fat diet at 6 months, while no significant difference between these two diets was observed among participants carrying other genotypes. The gene-diet interactions on changes in HDL-cholesterol and tri­glyc­erides were replicated in the DIRECT (pooled P for interaction ≤ 0.01). Similar results on trajectory of changes in HDL cholesterol and triglycerides over the 2 year intervention were observed in both trials. Our study provides replicable evidence that individuals with the CETP rs3764261 CC genotype might derive greater effects on raising HDL cholesterol and lowering triglycerides by choosing a low-carbohydrate/high-fat weight-loss diet instead of a low-fat diet.     

Resistin levels are related to fat mass,but not to body mass index in children

The relationship of resistin levels with obesity remains unclear. The aim of this study was to determine resistin levels in prepubertal children and adolescents and evaluate their association with anthropometric parameters and body composition. The study population included 420 randomly selected 6–8-year-old children and 712 children aged 12–16 years. Anthropometric data were measured and body mass index (BMI) and waist-to-hip and waist-to-height ratios were calculated. Body composition was assessed using an impedance body composition analyzer. Serum resistin levels were determined using a multiplexed bead immunoassay. Resistin levels were not significantly different between sexes. No significant differences in serum resistin concentrations were found between obese, overweight, and normal weight children at any age, and no significant correlations were observed between resistin concentrations and weight or BMI. However, resistin levels showed a significant positive correlation with fat mass in 12–16-year-old children, particularly in girls. In addition to describing serum resistin levels in prepubertal children and adolescents, our study suggests that resistin is related to body fat rather than to BMI in adolescents.     

Randomized controlled trial of chewing gum for weight loss

The possible effects on body weight of chewing gum on a regular schedule have not been tested in a randomized controlled trial (RCT). We conducted an 8-week RCT in 201 overweight and obese adults to test the hypothesis that receiving printed material on good nutrition and chewing gum for a minimum of 90 min/day (n = 102) would lead to greater weight loss than receiving printed nutrition information only (n = 99). Changes in BMI, waist circumference, and blood pressure were secondary outcomes. Adherence to the gum-chewing protocol in the intervention group was >95%. In the intention-to-treat analysis, there were virtually no changes in weight or BMI in either group between baseline and the end of the intervention at 8 weeks. Waist circumference decreased significantly in the intervention group between baseline and 8 weeks (mean ± SD change = -1.4 ± 5.3 cm; P = 0.0128); however, there was no significant difference in change in waist circumference comparing the groups. Similarly, systolic and diastolic blood pressure decreased significantly in the intervention group between baseline and 8 weeks (-3.0 ± 9.9 mm Hg; P = 0.0032 and -3.2 ± 7.3 mm Hg; P = 0.0001, respectively); however, there were no significant differences in the changes in systolic or diastolic blood pressure between the groups. Analyses including completers only produced essentially the same results. We conclude that chewing gum on a regular schedule for 8 weeks did not facilitate weight loss in these overweight and obese adults.