Mediators of Weight Loss and Weight Loss Maintenance in Middle‐aged Women

Long‐term behavioral self‐regulation is the hallmark of successful weight control. We tested mediators of weight loss and weight loss maintenance in middle‐aged women who participated in a randomized controlled 12‐month weight management intervention. Overweight and obese women (N = 225, BMI = 31.3 ± 4.1 kg/m²) were randomly assigned to a control or a 1‐year group intervention designed to promote autonomous self‐regulation of body weight. Key exercise, eating behavior, and body image variables were assessed before and after the program, and tested as mediators of weight loss (12 months, 86% retention) and weight loss maintenance (24 months, 81% retention). Multiple mediation was employed and an intention‐to‐treat analysis conducted. Treatment effects were observed for all putative mediators (Effect size: 0.32–0.79, P < 0.01 vs. controls). Weight change was ?7.3 ± 5.9% (12‐month) and ?5.5 ± 5.0% (24‐month) in the intervention group and ?1.7 ± 5.0% and ?2.2 ± 7.5% in controls. Change in most psychosocial variables was associated with 12‐month weight change, but only flexible cognitive restraint (P < 0.01), disinhibition (P < 0.05), exercise self‐efficacy (P < 0.001), exercise intrinsic motivation (P < 0.01), and body dissatisfaction (P < 0.05) predicted 24‐month weight change. Lower emotional eating, increased flexible cognitive restraint, and fewer exercise barriers mediated 12‐month weight loss (R² = 0.31, P < 0.001; effect ratio: 0.37), but only flexible restraint and exercise self‐efficacy mediated 24‐month weight loss (R² = 0.17, P < 0.001; effect ratio: 0.89). This is the first study to evaluate self‐regulation mediators of weight loss and 2‐year weight loss maintenance, in a large sample of overweight women. Results show that lowering emotional eating and adopting a flexible dietary restraint pattern are critical for sustained weight loss. For long‐term success, interventions must also be effective in promoting exercise intrinsic motivation and self‐efficacy.     

Evidence in Female Rhesus Monkeys (Macaca mulatta) that Nighttime Caloric Intake is not Associated with Weight Gain

Objective: To evaluate the hypothesis that nighttime consumption of calories leads to an increased propensity to gain weight. Research Methods and Procedures: Sixteen female rhesus monkeys (Macaca mulatta) were ovariectomized and placed on a high‐fat diet to promote weight gain, and we examined whether monkeys that ate a high percentage of calories at night were more likely to gain weight than monkeys that ate the majority of calories during the day. Results: Within 6 weeks post‐ovariectomy, calorie intake and body weight increased significantly (129 ± 14%, p = 0.04; 103 ± 0.91%, p = 0.02, respectively). Subsequent placement on high‐fat diet led to further significant increases in calorie intake and body weight (368 ± 56%, p = 0.001; 113 ± 4.0%, p = 0.03, respectively). However, there was no correlation between the increase in calorie intake and weight gain (p = 0.34). Considerable individual variation existed in the percentage of calories consumed at night (6% to 64% total daily caloric intake). However, the percentage of calorie intake occurring at night was not correlated with body weight (r = 0.04; p = 0.87) or weight gain (r = 0.07; p = 0.79) over the course of the study. Additionally, monkeys that showed the greatest nighttime calorie intake did not gain more weight (p = 0.94) than monkeys that showed the least nighttime calorie intake. Discussion: These results show that eating at night is not associated with an increased propensity to gain weight, suggesting that individuals trying to lose weight should not rely on decreasing evening calorie intake as a primary strategy for promoting weight loss.     

Effect of Weight Loss on High‐Molecular Weight Adiponectin in Obese Children

Our aim was to determine the influence of weight reduction on total (T‐) and high‐molecular weight (HMW‐) adiponectin in obese (OB) prepubertal children. Seventy OB prepubertal white patients were followed for 18 months and studied after reducing their BMI by 1 (n = 51) and 2 standard deviation scores (SDS) (n = 21) under conservative treatment, and 6 months after achieving weight loss (n = 44). Body composition dual‐energy X‐ray absorptiometry (DXA) and serum levels of T‐ and HMW‐adiponectin, resistin, leptin, leptin soluble receptor (sOB‐R), tumoral necrosis factor‐α and interleukin‐6 were determined. The control group consisted of 61 healthy prepubertal children. At diagnosis T‐adiponectin was higher (P < 0.01; confidence interval (+0.04) — (+0.15)) and HMW‐adiponectin lower (P < 0.001; confidence interval (?0.45) ? (?0.21)) in OB children than in controls. A reduction in body fat increased T‐ and HMW‐adiponectin and sOB‐R (all P < 0.001) and decreased leptin (P < 0.001) and interleukin‐6 levels (P < 0.05). After 6 months of sustained weight reduction a decrease in tumoral necrosis factor‐α (P < 0.01) occurred, whereas weight recovery increased leptin (P < 0.001) and decreased T‐adiponectin (P < 0.05). HMW‐adiponectin levels negatively correlated with homeostasis model assessment (HOMA) index and BMI in the whole cohort (both P < 0.001), as did T‐adiponectin levels and HOMA index in OB patients (P < 0.01), but neither T‐ nor HMW‐adiponectin correlated with body fat content (BFC) in OB children. We conclude that the impairment of T‐ and HMW‐adiponectin levels in childhood obesity is different to that in elder OB patients, showing closer relationship with carbohydrate metabolism parameters than with BFC, but increasing their levels after weight loss and in association with metabolic improvement.     

Feeding Frequency and Appetite in Lean and Obese Prepubertal Children

To determine the effect of feeding frequency on appetite in normal weight (NW) and obese (OB) prepubertal children, we carried out a prospective, randomized interventional study of 18 NW and 17 OB children ages 6–10. Children received three or five feedings in random order on separate days. Total calories, carbohydrate, protein, and fat composition on each day were equal. Two hours following the last feeding, children were offered ice cream ad lib. The major outcome variable was kilocalories ice cream consumed. A visual analog scale to assess fullness was also administered before consumption of ice cream. We observed that OB children consumed 73.0 ± 37.4 kcal more after five feedings than after three feedings whereas the NW children consumed 47.1 ± 27.8 kcal less. There was significant interaction between meal pattern and weight group indicating that this change in ice cream consumption differed significantly between groups (P = 0.014 by two‐factor analysis). Ice cream intake/kg was less in OB compared to NW subjects (P = 0.012). Fullness ratings before ice cream did not differ by meal pattern or weight group. However, pre‐ice cream fullness predicted ice cream intake in NW but not OB children. In summary, OB and NW children differed in appetite response to meal frequency. Our data suggest that: (i) satiety in OB children is related more to proximity of calories (larger supper) than to antecedent distribution of calories and; (ii) NW children may be more prone to restrict intake based on subjective fullness.     

Young Adults' Performance in a Low‐Intensity Weight Loss Campaign

Young adults (YA) are underrepresented in behavioral weight loss programs and achieve poorer outcomes than older adults (OA). There has been a call to develop programs specifically targeting this age group. This study examined the performance of YA enrolled in a low‐intensity, team‐based weight loss campaign and compared their outcomes to OA to determine the utility of such an approach for weight loss in this population. Shape Up Rhode Island (SURI) 2009 was a 12‐week online team‐based weight loss and exercise competition (N = 6,795, 81% female, 94% white, age = 44.7 ± 11.2, BMI = 29.4 ± 5.9). YA was defined as 18–35 years and OA as >35 years; YA and OA were compared on enrollment, retention, weight loss, and change in steps. A total of 1,562 YA enrolled and 715 completed the program. Fewer YA completed compared with OA (46 vs. 62%, P < 0.001). However, among completers, YA achieved greater percent weight loss (‐4.5 ± 4.0 vs. ?3.8 ± 3.2%) and greater daily step change (+1,578.2 ± 3,877.2 vs. +1,342.2 ± 3,645.7) than OA (P's < 0.001). Further, more YA completers achieved a ≥5% weight loss (40 vs. 29%, P < 0.001). Findings were consistent in the overweight/obese (OW/OB) subsample, and using ≤25 years of age as the cut off for YA. Weight losses among YA in this low‐intensity weight loss campaign were quite promising, with over 700 YA completing the program and on average achieving a 4.5% weight loss. Indeed, the potential public health impact of such an approach is substantial; future efforts to develop programs for this age group may benefit from using a low‐intensity, team‐based approach.     

Independent Evolution of Heart Autonomic Function and Insulin Sensitivity During Weight Loss

In order to investigate the improvement of insulin resistance and cardiac autonomic function along massive weight loss, 12 obese women were evaluated before, and 3 and 12 months after Roux‐en‐Y gastric bypass. The 12‐month values were compared to those of BMI‐matched controls. Insulin sensitivity was assessed by euglycemic clamp and the cardiac autonomic function by the analysis of the Heart Rate Variability (HRV). After surgery, glucose uptake progressively increased from 4.3 ± 0.5 mg/kg lean body mass (LBM)/min preoperative (pre‐op) to 4.9 ± 0.5 and 7.0 ± 0.5, 3‐ and 12‐month postoperative (post‐op) (P = 0.04 and P = 0.006 vs. pre‐op), whereas the cardiac autonomic function showed a biphasic pattern. HRV values increased 3 months post‐op, and decreased at 12 months, thus indicating an early sympathetic withdrawal followed by a later reactivation (e.g., the standard deviation of the normal‐to‐normal intervals was 116 ± 7 ms in pre‐op, 161 ± 10 at 3 months, P = 0.008 vs. pre‐op, and 146 ± 15 at 12 months, P = 0.03 vs. pre‐op and P = 0.02 vs. 3 m). Insulin sensitivity was significantly related to body weight (P = 0.02), whereas the cardiac indexes were significantly linked to the profile of energy intake (e.g., HRV triangular index vs. energy intake P = 0.003). No significant relationship linked insulin sensitivity to the cardiac autonomic indexes. Insulin sensitivity and cardiac parameters of the 12‐month post‐op patients were similar to their matched controls. During massive weight loss, the cardiac autonomic deregulation and insulin resistance improved concomitantly but independently from each other. Our results suggest that the extent of the improvement is associated with the final body weight.     

Reductions in Internal Disinhibition During Weight Loss Predict Better Weight Loss Maintenance

The construct of disinhibition, as measured by the Eating Inventory, was recently found to have two factors: internal disinhibition (eating in response to cognitive and emotional cues) and external disinhibition (eating in response to environmental cues). This study examined whether early changes in disinhibition that occurred during a weight loss program predicted later weight loss maintenance. Participants were adults enrolled in a weight loss treatment study (n = 81, 16% men, BMI = 38.4 ± 6.5 kg/m²). Two‐thirds of participants were African Americans. Participants received a uniform, meal‐replacement‐based weight loss program in months 1–3 and one of four nutritionally focused programs for weight loss maintenance in months 4–12. Disinhibition and weight were assessed at clinic visits. Change in internal disinhibition from months 1–3 (i.e., the weight loss period) significantly predicted change in weight from month 4 to 12 (i.e., the weight maintenance period); this remained significant when treatment group, age, gender, ethnicity, baseline weight, baseline depression, baseline internal disinhibition, and initial weight loss were controlled for (P = 0.03). A comparable analysis examining change in external disinhibition found that it was not a significant predictor of weight maintenance (P = 0.43). Participants who experienced the biggest decreases in internal disinhibition during the initial phase of treatment had the most success maintaining their weight loss in the next phase of treatment. Long‐term weight loss outcomes may be improved by spending sufficient treatment time teaching strategies for reducing eating in response to internal cues.     

Oxidative Stress in Normal‐Weight Obese Syndrome

The normal‐weight obese (NWO) syndrome was identified in women whose body weight (BW) and BMI are normal but whose fat mass (FM) is >30%. In these subjects, an early inflammatory status has been demonstrated. The aim was to verify whether oxidative stress occurs in NWO. Sixty age‐matched white Italian women were studied and subdivided as follows: 20 normal‐weight individuals (NW) (BMI <25 kg/m²; FM% <30%); 20 NWO (BMI <25 kg/m²; FM% >30%); 20 preobese‐obese (OB) (BMI >25 kg/m²; FM% >30%). Anthropometric, body composition (by dual‐energy X‐ray absorptiometry) variables, plasma levels of some cytokines, reduced glutathione (GSH), lipid hydroperoxide (LOOH), nitric oxide (NO) metabolites (NO₂^?/NO₃^?), antioxidant nonproteic capacity (ANPC) were measured and compared between groups. Glucose and lipid metabolism parameters were assessed. GSH and NO₂^?/NO₃^? levels resulted lower in OB and NWO compared to NW (P < 0.01). LOOH levels resulted higher in OB and NWO (P < 0.01). ANPC in NWO was lower than NW but higher with respect to OB (P < 0.01). Correlation analysis revealed strong associations between GSH levels and BW, BMI, FM% (R = ?0.45, at least P < 0.05); waist circumference (W) (R = ?0.33, P < 0.05); FFM% (R = 0.45, P < 0.01); IL‐1α, IL‐6, IL‐10, IL‐15 (R = ?0.39, ?0.33, ?0.36 ?0.34, respectively, P < 0.05); triglycerides (R = ?0.416, P < 0.05). LOOH levels were negatively related to FFM% (R = ?0.413, P < 0.05) and positively to FM%, IL‐15, TNF‐α, insulin, total cholesterol, low‐density lipoprotein cholesterol, and triglycerides (R = 0.408, R = 0.502, R = 0.341, R = 0.412, R = 0.4036, R = 0.405, R = 0.405, respectively, P < 0.05). The study clearly indicates that NWO, besides being in early inflammatory status, are contextually exposed to an oxidative stress related to metabolic abnormalities occurring in obesity.     

Enhanced Weight Loss With Pramlintide/Metreleptin: An Integrated Neurohormonal Approach to Obesity Pharmacotherapy

The neurohormonal control of body weight involves a complex interplay between long‐term adiposity signals (e.g., leptin), and short‐term satiation signals (e.g., amylin). In diet‐induced obese (DIO) rodents, amylin/leptin combination treatment led to marked, synergistic, fat‐specific weight loss. To evaluate the weight‐lowering effect of combined amylin/leptin agonism (with pramlintide/metreleptin) in human obesity, a 24‐week, randomized, double‐blind, active‐drug‐controlled, proof‐of‐concept study was conducted in obese or overweight subjects (N = 177; 63% female; 39 ± 8 years; BMI 32.0 ± 2.1 kg/m²; 93.3 ± 13.2 kg; mean ± s.d.). After a 4‐week lead‐in period with pramlintide (180 µg b.i.d. for 2 weeks, 360 µg b.i.d. thereafter) and diet (40% calorie deficit), subjects achieving 2–8% weight loss were randomized 1:2:2 to 20 weeks of treatment with metreleptin (5 mg b.i.d.), pramlintide (360 µg b.i.d.), or pramlintide/metreleptin (360 µg/5 mg b.i.d.). Combination treatment with pramlintide/metreleptin led to significantly greater weight loss from enrollment to week 20 (?12.7 ± 0.9%; least squares mean ± s.e.) than treatment with pramlintide (?8.4 ± 0.9%; P < 0.001) or metreleptin (?8.2 ± 1.3%; P < 0.01) alone (evaluable, N = 93). The greater reduction in body weight was significant as early as week 4, and weight loss continued throughout the study, without evidence of a plateau. The most common adverse events with pramlintide/metreleptin were injection site events and nausea, which were mostly mild to moderate and decreased over time. These results support further development of pramlintide/metreleptin as a novel, integrated neurohormonal approach to obesity pharmacotherapy.     

A Pilot Internet‐Based Behavioral Weight Loss Intervention with or without Commercially Available Portion‐Controlled Foods

Objective : To evaluate the short‐term impact of portion‐controlled food provision in combination with an Internet behavioral weight loss program on weight, blood cholesterol, and blood glucose levels. Design and Methods : Fifty participants, mean age 46 ± 10.7 years and mean body mass index 35.1 ± 3.8 kg/m², were randomized to one of two study groups, an Internet behavioral weight loss program (Internet‐alone; n = 25) or an Internet behavioral weight loss program plus a commercially available portion‐controlled diet (Internet + PCD; n = 25) for 12 weeks. Results : An intent‐to‐treat analysis found that the mean weight change in the Internet + PCD group was ?5.7 ± 5.6 kg and in the Internet‐alone group (n = 25) was ?4.1 ± 4.0 kg (P = 0.26). Participants in the Internet + PCD group achieved significantly greater improvements in blood glucose (?2.6 ± 5.7 vs. 1.4 ± 11.0 mg/dl; P = 0.05) and LDL cholesterol (?8.2 ± 18.0 vs. ?0.6 ± 21.0 mg/dl; P = 0.04), compared with Internet‐alone group. Conclusions : These data suggest that there may be short‐term clinical benefit in using a PCD in conjunction with a behavioral Internet‐based weight loss program to enhance weight loss and improve health indicators.     

Weight Loss With Naltrexone SR/Bupropion SR Combination Therapy as an Adjunct to Behavior Modification: The COR‐BMOD Trial

This 56‐week, randomized, placebo‐controlled trial examined the efficacy and safety of naltrexone plus bupropion as an adjunct to intensive behavior modification (BMOD). A total of 793 participants (BMI = 36.5 ± 4.2 kg/m²) was randomly assigned in a 1:3 ratio to: (i) placebo + BMOD (N = 202); or (ii) naltrexone sustained‐release (SR, 32 mg/day), combined with bupropion SR (360 mg/day) plus BMOD (i.e., NB32 + BMOD; N = 591). Both groups were prescribed an energy‐reduced diet and 28 group BMOD sessions. Co‐primary end points were percentage change in weight and the proportion of participants who lost ≥5% weight at week 56. Efficacy analyses were performed on a modified intent‐to‐treat population (ITT; i.e., participants with ≥1 postbaseline weight while taking study drug (placebo + BMOD, N = 193; NB32 + BMOD, N = 482)). Missing data were replaced with the last observation obtained on study drug. At week 56, weight loss was 5.1 ± 0.6% with placebo + BMOD vs. 9.3 ± 0.4% with NB32 + BMOD (P < 0.001). A completers analysis revealed weight losses of 7.3 ± 0.9% (N = 106) vs. 11.5 ± 0.6% (N = 301), respectively (P < 0.001). A third analysis, which included all randomized participants, yielded losses of 4.9 ± 0.6 vs. 7.8 ± 0.4%, respectively (P < 0.001). Significantly more NB32 + BMOD‐ vs. placebo + BMOD‐treated participants lost ≥5 and ≥10% of initial weight, and the former had significantly greater improvements in markers of cardiometabolic disease risk. NB32 + BMOD was generally well tolerated, although associated with more reports of nausea than placebo + BMOD. The present findings support the efficacy of combined naltrexone/bupropion therapy as an adjunct to intensive BMOD for obesity.     

Weight loss and improved gross motor coordination in children as a result of multidisciplinary residential obesity treatment

This study evaluated the short‐term effectiveness of a multidisciplinary residential obesity treatment program by describing changes in body weight, related measures, and gross motor co‐ordination. Secondarily, it was examined to what extent the amount of relative weight loss achieved by overweight and obese (OW/OB) participants explained the projected improvement in gross motor co‐ordination. Thirty‐six OW/OB children (aged 10.5 ± 1.4 years, 12 girls and 24 boys) were recruited at the Zeepreventorium VZW (De Haan, Belgium), where they followed a specific program consisting of moderate dietary restriction, psychological support, and physical activity. For reference purposes, an additional group of 36 age‐ and gender‐matched healthy‐weight (HW) children was included in the study. Anthropometric measures were recorded and gross motor co‐ordination was assessed using the Körperkoordinationstest für Kinder (KTK) on two occasions with an interval of 4 months. Regardless of the test moment, OW/OB participants displayed significantly poorer KTK performances (P < 0.001). However, treatment was found to be efficacious in decreasing body weight (Δ 17.9 ± 3.1%, P < 0.001) and generating a significant progress in gross motor co‐ordination performance, with a greater increase in KTK score(s) from baseline to re‐test as compared to HW peers (P < 0.01). Within the OW/OB group, the amount of relative weight loss explained 26.9% of the variance in improvement in overall KTK performance. Therefore, multidisciplinary residential treatment and concomitant weight loss can be considered an important means to upgrade OW/OB children's level of gross motor co‐ordination, which in turn may promote physical activity participation.     

Sex difference in the relationship between the hypothalamic-pituitary-adrenal axis and sex hormones in obesity

Objective: This study was carried out to investigate the role of sex in the regulation of the hypothalamic‐pituitary‐adrenal (HPA) axis and its relationship with testosterone levels in male and female obesity. Research Methods and Procedures: Twenty‐two obese men (OB‐M) and 29 obese women (OB‐W) participated in the study. Two groups of normal weight men (NW‐M) and women (NW‐W), respectively, served as controls. In basal conditions, blood concentrations of major androgens, sex hormone—binding protein, and gonadotropins were assessed, and the free androgen index (testosterone ×100/ sex hormone‐binding globulin) was calculated. All subjects underwent a combined corticotropin‐releasing hormone plus arginine‐vasopressin stimulation test. Results: OB‐M and NW‐M had higher basal adrenal cortical tropic hormone (ACTH) and cortisol levels than their female counterparts. In addition, ACTH, but not cortisol basal, levels were significantly higher in obese than in normal weight controls in both sexes. OB‐W had a higher response than OB‐M to the combined corticotropin‐releasing hormone plus arginine‐vasopressin test of both ACTH and cortisol [expressed as incremental percentage of area under the curve (AUC%)]. The same finding was present between NW‐W and NW‐M. Basal luteinizing hormone levels were negatively correlated to ACTH_AUC% in both OB‐W and OB‐M. In the OB‐W, however, a positive correlation was found between cortisol_AUC% and testosterone (r = 0.48; p = 0.002), whereas a tendency toward a negative correlation was present in OB‐M. Discussion: In conclusion, we have shown a significant positive relationship between the activity of the HPA axis and testosterone in obese women, which suggests a partial responsibility of increased HPA axis activity in determining testosterone levels. In addition, it clearly seems that, as reported in normal weight subjects, a sex difference in the HPA axis activity still persists even in the presence of obesity.     

Prevention of Weight Gain in Adult Patients With Type 2 Diabetes Treated With Pioglitazone

Pioglitazone, a thiazolidinedione (TZD) commonly used to treat type 2 diabetes, is associated with weight gain. Our study was designed to examine the effectiveness of three lifestyle‐treatment programs of varying intensity on prevention of pioglitazone‐induced weight gain and to measure the composition of the change in body weight. Thirty‐nine adult overweight and obese subjects with type 2 diabetes mellitus were all treated with pioglitazone and prospectively randomized to one of three lifestyle‐treatment programs with increasing level of intensity for 24 weeks. Body composition was measured by dual‐energy X‐ray absorptiometry (DXA), computed tomography, and multifrequency bioimpedance analysis both before and after therapy. Subjects demonstrated a “dose‐response” effectiveness to three levels of lifestyle intervention to mitigate pioglitazone‐induced weight gain. Mean (s.d.) weight change (kg) for the usual, standard, and intensive lifestyle groups were 4.9 ± 4.9 (P = 0.005), 1.8 ± 3.4 (P = 0.02), and ?0.2 ± 4.4 (NS) respectively. Total body fat increased 2.6 ± 3.4 kg (P = 0.04) for the usual group and decreased for the intensive group ?0.4 ± 3.5 (NS). Change in abdominal subcutaneous and visceral adipose tissue (VAT) did not differ between groups, although ratio of visceral/subcutaneous fat decreased for the standard and intensive groups (NS). Both usual (P < 0.05) and standard care (NS) groups gained total body water. This is the first prospective, randomized study that demonstrates the beneficial effect of participation in a comprehensive lifestyle‐weight‐management program on lessening of weight gain associated with pioglitazone.     

Severely Obese Have Greater LPS‐stimulated TNF‐α Production Than Normal Weight African‐American Women

Obesity is associated with an increase in chronic, low‐grade inflammation which has been implicated in the development of type 2 diabetes mellitus and cardiovascular disease. The purpose of this study was to determine whether obesity was associated with an elevation of whole blood lipopolysaccharide (LPS)‐stimulated tumor necrosis factor‐α (TNF‐α) production. African‐American women were recruited from a larger study and assigned to one of five groups based on BMI: normal weight (NORM; BMI 20–25, n = 7), overweight (OVER; BMI 25–30, n = 12), class 1 obese (OB1; BMI 30–35, n = 19), class 2 obese (OB2; BMI 35–40, n = 10), or class 3 obese (OB3; BMI >40, n = 17). Body composition was determined via a whole body dual‐energy X‐ray absorptiometry (DXA) scan. Venous blood samples were collected following an overnight fast (>8 h), and stimulated with five doses of LPS (Salmonella enteriditis): 80, 40, 20, 10, and 5 µg/ml for 24 h in a 37 °C, 5% CO₂ incubator. Following stimulation, TNF‐α was measured using enzyme‐linked immunosorbent assay. OB3 produced 365% more TNF‐α than NORM at an LPS dose of 20 µg/ml (P < 0.05). When maximal TNF‐α production was assessed regardless of LPS dose, OB3 produced 230% more than NORM and OVER produced 190% more than NW (P = 0.001). Total and trunk fat mass and BMI were significantly correlated with maximal TNF‐α production and LPS = 20 µg/ml. Our findings are consistent with previous reports suggesting a relationship between increased adiposity and inflammatory marker production. This is one of the first studies to focus on African‐American women, who have higher rates of obesity.     

Physical activity patterns using accelerometry in the National Weight Control Registry

The National Weight Control Registry (NWCR) was established in 1993 to examine characteristics of successful weight‐loss maintainers. This group consistently self‐reports high levels of physical activity. The aims of this study were to obtain objective assessments of physical activity in NWCR subjects and compare this to physical activity in both normal‐weight and overweight controls. Individuals from the NWCR (n = 26) were compared to a never obese normal‐weight control group matched to the NWCR group's current BMI (n = 30), and an overweight control group matched to the NWCR group's self‐reported pre‐weight‐loss BMI (n = 34). Objective assessment of physical activity was obtained for a 1‐week period using a triaxial accelerometer. Bouts of moderate‐to‐vigorous physical activity (MVPA) ≥10 min in duration, as well as nonbout MVPA (bouts of MVPA 1–9 min in duration) were summed and characterized. NWCR subjects spent significantly (P = 0.004) more time per day in sustained bouts of MVPA than overweight controls (41.5 ± 35.1 min/day vs. 19.2 ± 18.6 min/day) and marginally (P = 0.080) more than normal controls (25.8 ± 23.4). There were no significant differences between the three groups in the amount of nonbout MVPA. These results provide further evidence that physical activity is important for long‐term maintenance of weight loss and suggest that sustained volitional activity (i.e., ≥10 min in duration) may play an important role. Interventions targeting increases in structured exercise may be needed to improve long‐term weight‐loss maintenance.     

Effect of Energy‐Reduced Diets High in Dairy Products and Fiber on Weight Loss in Obese Adults

Objective: Studies suggest that high‐dairy and high‐fiber/low‐glycemic index diets may facilitate weight loss, but data are conflicting. The effects on weight loss and body fat of a high‐dairy diet and a diet high in dairy and fiber and low in glycemic index were compared with a standard diet. Research Methods and Procedures: Ninety obese subjects were recruited into a randomized trial of three diets designed to provide a calorie deficit of 500 calories/d over a 48‐week period. The study compared a moderate (not low)‐calcium diet with a high‐calcium diet. Results: Seventy‐two subjects completed the study. Significant weight and fat loss occurred with all three diets. A diet with 1400 mg of calcium did not result in greater weight (11.8 ± 6.1 kg) or fat (9.0 ± 6.0 kg) loss than a diet with 800 mg of calcium (10.0 ± 6.8 and 7.5 ± 6.6 kg, respectively). A diet with 1400 mg of calcium, increased fiber content, and fewer high‐glycemic index foods did not result in greater weight (10.6 ± 6.8 kg) or fat (8.5 ± 7.8 kg) loss than the standard diet with 800 mg of calcium. Lipid profile, high‐sensitivity C‐reactive protein, leptin, fasting glucose, and insulin improved significantly, but there were no significant differences between the experimental diets and the control diet. Discussion: We found no evidence that diets higher than 800 mg of calcium in dairy products or higher in fiber and lower in glycemic index enhance weight reduction beyond what is seen with calorie restriction alone.     

The Effect of Mannan Oligosaccharide Supplementation on Body Weight Gain and Fat Accrual in C57Bl/6J Mice

The prevalence of obesity in industrialized societies has become markedly elevated. In contrast, model organism research shows that reducing caloric intake below ad libitum levels provides many health and longevity benefits. Despite these benefits, few people are willing and able to reduce caloric intake over prolonged periods. Prior research suggests that mannooligosaccharide (MOS or mannan) supplementation can increase lifespan of some livestock and in rodents can reduce visceral fat without reducing caloric intake. Hence, we tested the effect of MOS supplementation as a possible calorie restriction (CR) mimetic (CRM) in mice. C57Bl/6J male mice were fed a high‐fat “western” type diet with or without 1% MOS (by weight) supplementation (n = 24/group) from 8 to 20 weeks of age. Animals were housed individually and provided 95% of ad libitum food intake throughout the study. Body weight was measured weekly and body composition (lean and fat mass) measured noninvasively every 3 weeks. Individual fat depot weights were acquired by dissection at study completion. Supplementation of a high‐fat diet with 1% MOS tended to reduce total food intake (mean ± s.d.; control (CON): 293.69 ± 10.53 g, MOS: 288.10 ± 11.82 g; P = 0.09) during the study. Moreover, MOS supplementation had no significant effect on final body weight (CON: 25.21 ± 2.31 g, MOS: 25.28 ± 1.49 g; P = 0.91), total fat (CON: 4.72 ± 0.90 g, MOS: 4.82 ± 0.83 g; P = 0.69), or visceral fat (CON: 1.048 ± 0.276 g, MOS: 1.004 ± 0.247 g; P = 0.57). Contrary to previous research, MOS supplementation had no discernable effect on body weight gain or composition during this 12‐week study, challenging the potential use of MOS as a CRM or body composition enhancer.     

Provision of Foods Differing in Energy Density Affects Long‐Term Weight Loss

Objective: The energy density (kilocalories per gram) of foods influences short‐term energy intake. This 1‐year clinical trial tested the effect on weight loss of a diet incorporating one or two servings per day of foods equal in energy but differing in energy density. Research Methods and Procedures: Dietitians instructed 200 overweight and obese women and men to follow an exchange‐based energy‐restricted diet. Additionally, subjects were randomized to consume daily either one or two servings of low energy‐dense soup, two servings of high energy‐dense snack foods, or no special food (comparison group). Results: All four groups showed significant weight loss at 6 months that was well maintained at 12 months. The magnitude of weight loss, however, differed by group (p = 0.006). At 1 year, weight loss in the comparison (8.1 ± 1.1 kg) and two‐soup (7.2 ± 0.9 kg) groups was significantly greater than that in the two‐snack group (4.8 ± 0.7 kg); weight loss in the one‐soup group (6.1 ± 1.1 kg) did not differ significantly from other groups. Weight loss was significantly correlated with the decrease in dietary energy density from baseline at 1 and 2 months (p = 0.0001) but not at 6 and 12 months. Discussion: On an energy‐restricted diet, consuming two servings of low energy‐dense soup daily led to 50% greater weight loss than consuming the same amount of energy as high energy‐dense snack food. Regularly consuming foods that are low in energy density can be an effective strategy for weight management.     

Cognitive Change in Obese Adolescents Losing Weight

Objectives: To investigate how obese adolescents think about themselves in terms of exercise, eating, and appearance and whether these cognitions change over the course of a residential weight loss camp. Research Methods and Procedures: Obese adolescents [N = 61; age, 14.1 (±0.2) years; BMI, 33.9 (±0.7) kg/m²] completed assessments of body weight and height and self‐esteem and a sentence‐completion test eliciting thoughts and beliefs about exercise, eating, and appearance at the start and end of the camp (mean stay, 26 days). They were compared with a single assessment of 20 normal‐weight adolescents [age, 15.4 (±0.2) years; BMI, 21.8 (±0.5) kg/m²]. Results: The obese adolescents lost 5.7 kg and reduced their BMI SD score by 0.25. Camp residence was associated with a significant reduction in the number of negative automatic thoughts and an increase in positive thoughts, especially related to exercise and appearance. There was no change in conditional beliefs, either functional or dysfunctional. Including BMI SD score change as a covariate took away all the main and interaction effects of time, showing that cognitive change was largely accounted for by the reduction in weight. Despite this improvement, campers remained cognitively more negative and dysfunctional than the normal‐weight comparison adolescents. Discussion: Obese adolescents not only lost weight, but they improved their self‐representation, specifically in terms of automatic thoughts about exercise and appearance. Although these are short‐term cognitive changes, they reflect positively on the camp experience and show the value of psychological improvement in assessing obesity‐treatment outcomes.