Amount of Food Group Variety Consumed in the Diet and Long‐Term Weight Loss Maintenance

Objective: Decreases in variety of foods consumed within high‐fat‐dense food groups and increases in variety of foods consumed within low‐fat‐dense food groups are associated with lower energy intake and greater weight loss during obesity treatment and may assist with weight loss maintenance. This study examined food group variety in 2237 weight loss maintainers in the National Weight Control Registry, who had lost 32.2 ± 18.0 kg (70.9 ± 39.5 lbs) and maintained a weight loss of at least 13.6 kg (30 lbs) for 6.1 ± 7.7 years. Research Methods and Procedures: At entry into the registry, registry members completed a food frequency questionnaire from which amount of variety consumed from different food groups was assessed. To provide a context for interpreting the level of variety occurring in the diet of registry participants, food group variety was compared between registry participants and 96 individuals who had recently participated in a behavioral weight loss program and had lost at least 7% of initial body weight. Results: Registry members reported consuming a diet with very low variety in all food groups, especially in those food groups higher in fat density. Registry participants consumed significantly (p < 0.001) less variety within all food groups, except fruit and combination foods, than recent weight losers after 6 months of weight loss treatment. Discussion: These results suggest that successful weight loss maintainers consume a diet with limited variety in all food groups. Restricting variety within all food groups may help with consuming a low‐energy diet and maintaining long‐term weight loss.     

Maintenance of weight loss in overweight middle-aged women through the Internet

Objective: The purpose of this study was to compare weight regain in a group of perimenopausal women (48.0 ± 4.4 years old), randomized to a 12‐month weight maintenance Internet intervention or to self‐directed weight maintenance after a 4‐month weight loss treatment. Methods and Procedures: After a 4‐month behavioral weight loss program, 135 women were randomized to either Internet or self‐directed groups. The Internet group (n = 66) used a website to gain information and complete logs concerning their weight, diet, and exercise progress over a 12‐month follow‐up. The 69 self‐directed women had no contact with study staff. All women were measured for weight and body composition, and diet intake, and were interviewed using the 7‐day physical activity questionnaires at baseline, 4 months, and 16 months. Results: At the end of the 12‐month follow‐up, the Internet and self‐directed groups had regained on average 0.4 ± 5.0 kg and 0.6 ± 4.0 kg, respectively (P = 0.5). In within‐group analyses, Internet diet‐log entries were correlated with follow‐up weight change (r = ?0.29; P < 0.05) and moderately with change in exercise energy expenditure (EEE; r = 0.44; P < 0.01). Follow‐up weight change was not correlated with change in dietary intake. Discussion: While significant weight loss was maintained over follow‐up by both groups of women, Internet use did not surpass self‐direction in helping to sustain weight loss. Among Internet users, Internet use was related to weight change and EEE.     

The Effect of Dietary Glycemic Index on Weight Maintenance in Overweight Subjects: A Pilot Study

Evidence suggests that a low‐glycemic index (LGI) diet has a satiating effect and thus may enhance weight maintenance following weight loss. This study was conducted at Hammersmith Hospital, London, UK, and assessed the effect of altering diet GI on weight‐loss maintenance. It consisted of a weight‐loss phase and a 4‐month randomized weight maintenance phase. Subjects were seen monthly to assess dietary compliance and anthropometrics. Appetite was assessed bimonthly by visual analogue scales while meal challenge postprandial insulin and glucose concentrations were assessed before and after the intervention. Following a median weight loss of 6.1 (interquartile range: 5.2–7.1) % body weight, subjects were randomized to a high‐glycemic index (HGI) (n = 19) or LGI (n = 23) diet. Dietary composition differed only in GI (HGI group: 63.7 ± 9.4; LGI group: 49.7 ± 5.7, P < 0.001) and glycemic load (HGI group: 136.8 ± 56.3; LGI group: 89.7 ± 27.5, P < 0.001). Groups did not differ in body weight (weight change over 4 months, HGI group: 0.3 ± 1.9 kg; LGI group: −0.7 ± 2.9 kg, P = 0.3) or other anthropometric measurements. This pilot study suggests that in the setting of healthy eating, changing the diet GI does not appear to significantly affect weight maintenance.     

Using telehealth to increase participation in weight maintenance programs

Objective: To compare weight regain, satisfaction, and convenience among three weight maintenance programs: telehealth, traditional classes, and no program. Research Methods and Procedures: This quasi‐experimental study compared weight change, satisfaction, and convenience among three program types. The telehealth participants interacted with a registered dietitian (RD) through the web and e‐mail, traditional program participants attended a traditional classroom program, and no program participants received no interaction. Eighty‐seven subjects (14 men and 73 women) were enrolled in the study: 31 traditional, 31 telehealth, and 25 no program participants. Eligibility included participation in a community‐based weight loss program (Colorado Weigh) and minimum 7% weight loss before enrollment. Results: Subject characteristics at baseline were as follows: age, 50 ± 9.3 (standard deviation) years; height, 1.68 ± 0.09 m; weight, 80.5 ± 18.4 kg, with no significant differences between groups. Over 6 months, the traditional group lost 0.5 ± 4.3 kg, the telehealth group lost 0.6 ± 2.5 kg, and the no program group gained 1.7 ± 3.0 kg. Weight change among all three groups was significant (p = 0.02); no program participants gained significantly more weight than the telehealth and traditional groups. There were no differences in overall satisfaction between the telehealth and traditional groups (p = 0.43), but individuals in the telehealth group rated their program as more convenient compared with the traditional group (p = 0.0001). Discussion: These results show the usefulness of telehealth programs in long‐term weight loss maintenance. They may be a useful alternative for those who successfully lose weight in a structured behavioral program but do not choose to participate in a formal behavioral weight loss maintenance program.     

A pilot randomized controlled trial of a commercial diet and exercise weight loss program in minority breast cancer survivors

Objective:

Obesity is associated with poorer breast cancer outcomes and losing weight postdiagnosis may improve survival. As Hispanic and black women have poorer breast cancer prognosis than non‐Hispanic whites diagnosed at similar age and stage, and have higher rates of obesity, effective weight loss strategies are needed. We piloted a randomized, waitlist‐controlled, crossover study to examine the effects and feasibility of the commercial Curves weight loss program among Hispanic, African American and Afro‐Caribbean breast cancer survivors.

Design and Methods:

Women with stage 0–IIIa breast cancer ≥6 months posttreatment, sedentary, and BMI ≥25 kg/m² were randomized to the immediate arm (IA): 6 months of the Curves program followed by 6 months of observation; or the waitlist control arm (WCA): 6 months of observation followed by 6 months of the Curves program. The Curves program uses a 30‐min exercise circuit and a high‐vegetable/low‐fat/calorie‐restricted diet.

Results:

A total of 42 women enrolled (79% Hispanic, 21% black), mean age 51 (range 32–69) and mean BMI 33.2(±5.9) kg/m²; 91% were retained at month 12. At month 6, women in the IA lost an average 3.3% (±3.5%) of body weight (range: 1.7% gain to 10.6% loss), as compared with 1.8% (±2.9%) weight loss in the WCA (P = 0.04). At month 12, on average women in the IA regained some but not all of the weight lost during the first 6 months (P = 0.02).

Conclusions:

Minority breast cancer survivors were recruited and retained in a weight loss study. Six months of the Curves program resulted in moderate weight loss, but weight loss was not maintained postintervention. Future interventions should identify methods to increase uptake and maintenance of weight loss behaviors.     

Effect of Internet Support on the Long‐Term Maintenance of Weight Loss

Objective: To investigate the efficacy of an Internet weight maintenance program. Research Methods and Procedures: Two hundred fifty‐five healthy overweight and obese adults (mean ± SD BMI, 31.8 ± 4.1 kg/m²) men (18%; mean ± SD age, 45.8 ± 8.9 yrs) participated in a 6‐month behavioral weight control program conducted over interactive television. Treatment was followed by a 12‐month weight maintenance program with three conditions: frequent in‐person support (F‐IPS), minimal in‐person support (M‐IPS) and internet support (IS). Main outcome measures included body weight, program adherence, and social influence components. Results: There were no significant differences among the groups in weight loss (mean ± SD) from baseline to 18 months (7.6 ± 7.3 kg vs. 5.5 ± 8.9 kg vs. 5.1 ± 6.5 kg, p = 0.23 for the IS, M‐IPS, and F‐IPS, respectively). Discussion: Participants assigned to an internet‐based weight maintenance program sustained comparable weight loss over 18 months compared with individuals who continued to meet face‐to‐face. Therefore, the internet appears to be a viable medium for promoting long‐term weight maintenance.     

Sertraline and Relapse Prevention Training Following Treatment by Very-Low-Calorie Diet: A Controlled Clinical Trial

WADDEN, THOMAS A, SUSAN J BARTLETT, GARY D FOSTER, ROBERT A GREENSTEIN, BARBARA J WINGATE, ALBERT J STUNKARD AND KATHLEEN A LETIZIA. Sertraline and relapse prevention training following treatment by very-low-calorie diet: a controlled clinical trial. Obes Res. This study examined the combination of sertraline, a selective serotonin reuptake inhibitor, and relapse prevention training in the maintenance of weight loss following treatment by a very-low-calorie diet. A total of 53 women who had lost a mean (± SD) of 22.9 ± 7.1 kg from a pretreatment weight of 103.1 ± 17.8 kg were randomly assigned to a 54-week weight maintenance program that was combined with either: 1) 200 mg/d of sertraline; or 2) placebo. During the first 6 weeks, sertraline subjects lost significantly more weight and reported significantly greater reductions in hunger and preoccupation with food than did subjects on placebo. After this time, however, women in both conditions regained weight steadily. The 13 sertraline subjects who completed the 54-week study regained 17.7 ± 10.6 kg of their original 26.3 ± 7.6 kg loss, equal to a regain of 70.9 ± 41.7%. The 17 placebo completers regained 11.8 ± 9.0 kg of their 23.4 ± 7.8 kg loss, equal to a 46.5 ± 34.6% regain. End-of-treatment differences between groups in weight change were not statistically significant. Nor were there significant differences between the two conditions at any time in changes in fat-free mass, resting metabolic rate or dysphoria, all of which tended to increase with weight regain. The results are discussed in relation to findings from other long-term studies that combined diet and medication.     

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.     

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.     

Changes in body composition with weight loss: obese subjects randomized to surgical and medical programs

Objective: To assess changes in body composition with weight loss in obese subjects randomized to a laparoscopic adjustable gastric band surgical program or a medical program using a very‐low‐energy diet and orlistat. Research Methods and Procedures: Using body composition measurements by DXA, neutron activation for total body nitrogen, and whole body γ counting for total body potassium, we studied changes in fat mass, fat distribution, fat‐free mass, total bone mineral content, total body protein, and body cell mass at 6 (n = 61 paired) and 24 months (n = 53 paired) after randomization. Results: At 24 months, the surgical group had lost significantly more weight (surgical, 20.3 ± 6.5 kg; medical, 5.9 ± 8.0 kg). There was favorable fat‐free mass to fat mass loss ratios for both groups (surgical, 1:5.5; medical, 1:5.9). Changes in total body nitrogen or potassium were favorable in each group. A small reduction in mean bone mineral content occurred throughout the study but was not associated with extent of weight loss or treatment group. At 6 months, weight loss for both groups was similar (surgical, 14.1 ± 4.5 kg; medical, 13.3 ± 7.3 kg). The medical program subjects lost less fat‐free mass and skeletal muscle and had increased total body protein. The proportion of body fat to limb fat remained remarkably constant throughout the study. Discussion: Weight loss programs used in this study induced fat loss without significant deleterious effects on the components of fat‐free mass.     

A Randomized Controlled Trial of a Commercial Internet Weight Loss Program

Objective: To assess, in a 1‐year randomized controlled trial, the efficacy of eDiets.com (a commercial Internet weight loss program) in improving weight, cardiovascular health, and quality of life. Research Methods and Procedures: Participants were 47 women with a mean age of 43.7 ± 10.2 (SD) years and a mean BMI of 33.5 ± 3.1 kg/m². They were randomly assigned to either: 1) eDiets.com , a commercial Internet‐based program available to the public; or 2) a weight loss manual (i.e., LEARN Program for Weight Control 2000). At baseline, participants in both groups met briefly with a psychologist who instructed them to follow the components of their program as closely as possible. Additional brief visits were provided at weeks 8, 16, 26, and 52 to review their progress. Change in weight was the main outcome measure. Results: At week 16, participants in eDiets.com lost 0.9 ± 3.2% of initial weight compared with 3.6 ± 4.0% for women assigned to the weight loss manual. At week 52, losses increased to 1.1 ± 4.0% and 4.0 ± 5.1%, respectively. Results of a last‐observation‐carried‐forward analysis found that women in the manual group lost significantly (p < 0.05) more weight (at both times) than those treated by eDiets.com . (Results, however, of baseline‐carried‐forward and completers analyses did not reach statistical significance.) There were no significant differences between groups in changes in cardiovascular risk factors or quality of life. Discussion: This study provides consumers with important information about the probable benefits they can expect from participating in a popular Internet‐based weight loss program.     

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.     

Weight loss goals among African-American women with type 2 diabetes in a behavioral weight control program

African‐American women with type 2 diabetes experience limited weight loss in behavioral weight control programs. Some research suggests that overly ambitious weight loss expectations may negatively affect weight losses achieved but it is unknown whether they affect weight loss among African‐American women. The current study examined personal weight loss goals and expected satisfaction with a reasonable weight loss among African‐American women with type 2 diabetes starting a behavioral obesity treatment. We also explored associations among these factors and weight loss treatment outcomes. Self‐identified African‐American women (N = 84) in a 24‐session group program were assessed at baseline and 6‐month follow‐up. At baseline, women indicated weight loss goals of 14.1 ± 6.6 kg (14% of initial weight). They also reported relatively high expected satisfaction with a reasonable weight loss (7–10%). On average, participants lost 3.0 ± 3.9 kg (3% of initial weight) and attended 73 ± 21% of group sessions. Neither weight loss goals nor expected satisfaction with a reasonable weight loss was correlated with either actual weight loss outcome or attendance. Having higher personal weight loss goals was associated with lower expectations of satisfaction with a reasonable weight loss. This suggests that African‐American women with type 2 diabetes enter treatment hoping to lose far more weight than they are likely to achieve. It is important to understand the psychosocial sequelae of failing to reach these goals on subsequent weight maintenance and future weight loss attempts within this population.     

Obesity Reduction Black Intervention Trial (ORBIT): 18‐Month Results

Obesity is a chronic condition that is prevalent in black women. The Obesity Reduction Black Intervention Trial (ORBIT) was a randomized controlled weight loss and weight‐loss maintenance (WLM) trial. Participants (N = 213) were randomized to the intervention or control groups in August 2005 and September 2006. Follow‐up data were collected 6 and 18 months after randomization. The main outcome was change in weight and BMI from baseline to 18 months. The mean weight at baseline was 104.9 kg, and the mean weight loss in the intervention group at 6 months was 3.0 kg and a gain of 0.2 kg in the control group (mean difference between groups in weight change at 6 months, adjusting for baseline weight and cohort, ?3.27 kg; 95% confidence interval (CI), ?4.50 to ?2.05 kg; P < 0.001). Both groups gained weight between 6 and 18 months (mean 1.0 kg in the intervention group and 0.1 kg in the control group). However, intervention participants lost significantly more weight than control participants during the 18‐month intervention (adjusted mean difference between groups at 18 months, ?2.83 kg; 95% CI, ?4.71 to ?0.95; P = 0.003). At 18 months, intervention participants were more likely than control participants to have lost at least 5% of baseline weight (24% vs. 12%, P < 0.04). Our results indicate that the ORBIT program did promote weight loss and weight‐loss maintenance. However, the results also clearly illustrate there is more to learn about what will contribute to meaningful weight loss and maintenance in this population.     

Impact of Diet‐Induced Weight Loss on the Cardiac Autonomic Nervous System in Severe Obesity

Objective: To determine the impact of diet‐induced weight loss on cardiac autonomic nervous system modulation and arrhythmias in subjects with severe obesity and the influence of a high‐fat or a high‐carbohydrate diet regimen on heart rate variability in reduced‐obese individuals. Research Methods and Procedures: Eight severely obese subjects (BMI ≥ 40.0 kg/m²) underwent a 3‐month weight loss program followed by a 3‐month reduced‐weight maintenance regimen. Thereafter, each subject was admitted for an inpatient period of 17 days on two separate occasions. A high‐carbohydrate (60%) or high‐fat (55%) diet of appropriate energy content for weight maintenance was prescribed during each inpatient phase. Heart rate variability was derived from a 24‐hour Holter monitoring system in all subjects during their inpatient stay. Cardiac Holter monitoring was performed at three occasions (baseline, diet phase I, and diet phase II), including the second night of a two overnight calorimetry chamber stay. Results: After the diet regimen, there was a 10% decrease in weight. There were no significant changes in systolic and diastolic blood pressure, arrhythmias, glucose, insulin, total cholesterol, low‐density lipoprotein‐cholesterol, high‐density lipoprotein‐cholesterol, respiratory exchange ratio, and resting energy expenditure between experiments. Mean heart rate was lower after weight loss compared with baseline (p < 0.001). After weight loss, there was an increase in the parasympathetic indices of heart rate variability showing an increase in cardiac vagal modulation (all p < 0.05). Discussion: Weight loss is associated with significant improvement in autonomic cardiac modulation through enhancement of parasympathetic modulation, which clinically translates into a decrease in heart rate.     

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.     

Three-year weight change in successful weight losers who lost weight on a low-carbohydrate diet

Objective: The purpose of this study was to evaluate long‐term weight loss and eating and exercise behaviors of successful weight losers who lost weight using a low‐carbohydrate diet. Research Methods and Procedures: This study examined 3‐year changes in weight, diet, and physical activity in 891 subjects (96 low‐carbohydrate dieters and 795 others) who enrolled in the National Weight Control Registry between 1998 and 2001 and reported ≥30‐lb weight loss and ≥1 year weight loss maintenance. Results: Only 10.8% of participants reported losing weight after a low‐carbohydrate diet. At entry into the study, low‐carbohydrate diet users reported consuming more kcal/d (mean ± SD, 1895 ± 452 vs. 1398 ± 574); fewer calories in weekly physical activity (1595 ± 2499 vs. 2542 ± 2301); more calories from fat (64.0 ± 7.9% vs. 30.9 ± 13.1%), saturated fat (23.8 ± 4.1 vs. 10.5 ± 5.2), monounsaturated fat (24.4 ± 3.7 vs. 11.0 ± 5.1), and polyunsaturated fat (8.6 ± 2.7 vs. 5.5 ± 2.9); and less dietary restraint (10.8 ± 2.9 vs. 14.9 ± 3.9) compared with other Registry members. These differences persisted over time. No differences in 3‐year weight regain were observed between low‐carbohydrate dieters and other Registry members in intent‐to‐treat analyses (7.0 ± 7.1 vs. 5.7 ± 8.7 kg). Discussion: It is possible to achieve and maintain long‐term weight loss using a low‐carbohydrate diet. The long‐term health effects of weight loss associated with a high‐fat diet and low activity level merits further investigation.     

The effects of weight loss on relative bone mineral density in premenopausal women

Objective:

This study compared BMD relative to body weight following a ～6‐month weight loss program and a 1‐year weight maintenance phase in premenopausal women and determined whether African American (AA) and European‐American (EA) women's BMD respond similarly during weight loss.

Design and Methods:

Premenopausal women (n = 115, 34 ± 5 years) were evaluated in an overweight state (BMI between 27 and 30 kg/m²), following an 800 kcal/day diet/exercise program designed to reduce BMI<25 kg/m², and 1‐year following weight loss.

Results:

BMD relative to body weight (Z‐scores) increased after weight loss, but decreased during the 1‐year weight maintenance phase. All 1‐year follow‐up BMD Z‐scores were increased (except L1) compared to baseline measurements (P < 0.05). These sites included the hip neck (+0.088, P = 0.014), total hip (+0.099, P = 0.001), L2 (+0.127, P = 0.013), L3 (+0.135, P = 0.014), and L4 (+0.199, P = 0.002). AAs had significantly higher absolute BMD at all sites (P < 0.05) compared to EAs, but no time by race interactions were evident during weight loss (except in L3).

Conclusion:

These results may indicate that weight loss is safe with regard to bone health for overweight premenopausal women.     

A randomized trial testing a contingency-based weight loss intervention involving social reinforcement

Even though behavioral weight loss interventions are conducted in groups, a social contingency (SC) paradigm that capitalizes on the social reinforcement potential of the weight loss group has never been tested. We tested a weight loss intervention in which participation in the weight loss group was contingent upon meeting periodic weight goals. We hypothesized that making access to the group dependent upon weight loss would improve weight outcomes. Participants (N = 62; 84% female; 94% white; age = 51.9 ± 9.0; BMI = 34.7 ± 4.5) were randomized to 6‐months of standard behavioral weight loss (SBWL) or to a behavioral program that included a SC paradigm. Both groups engaged in social cohesion activities. Participants in SC who did not meet weight goals did not attend group meetings; instead, they received individual treatment with a new interventionist and returned to group once their weight goals were met. SC did not improve overall weight loss outcomes (SC: ?10.0 ± 4.9 kg, SBWL: ?10.8 ± 6.4 kg, P = 0.63). Similarly, overall weight loss was not significantly different in the subgroup of participants in the SC and SBWL conditions who did not meet periodic weight loss goals (?7.3 ± 4.1 kg vs. ?7.1 ± 3.5 kg, P = 0.90). Surprisingly, “successful” SC participants (who met their weight goals) actually lost less weight than “successful” SBWL participants (?12.4 ± 3.2 kg vs. ?14.5 ± 4.7 kg, P = 0.02). Whereas contingency‐based treatments have been tested for other health behaviors (e.g., substance abuse), this is the first study to test a SC intervention for weight loss. This approach did not improve overall weight loss outcomes. Our attempt to offer appropriate clinical care by providing individual treatment to SC participants when needed may have mitigated the effects of the SC paradigm.     

Two-year internet-based randomized controlled trial for weight loss in African-American girls

Objective: A randomized controlled trial tested the efficacy of an internet‐based lifestyle behavior modification program for African‐American girls over a 2‐year period of intervention. Research Methods and Procedures: Fifty‐seven overweight (mean BMI percentile, 98.3) African‐American girls (mean age, 13.2 years) were randomly assigned to an interactive behavioral internet program or an internet health education program, the control condition. Overweight parents were also participants in the study. Forty adolescent‐parent dyads (70%) completed the 2‐year trial. Outcome data including BMI, body weight, body composition, and weight loss behaviors were collected at baseline and at 6‐month intervals. A computer server tracked use of the web sites. Results: An intention‐to‐treat statistical approach was used, with the last observation carried forward. In comparison with the control condition, adolescents in the behavioral program lost more mean body fat (BF) (?1.12 ± 0.47% vs. 0.43 ± 0.47% BF, p < 0.05), and parents in the behavioral program lost significantly more mean body weight (?2.43 ± 0.66 vs. ?0.35 ± 0.64 kg, p < 0.05) during the first 6 months. This weight loss was regained over the next 18 months. After 2 years, differences in fat for adolescents (?0.08 ± 0.71% vs. 0.84 ± 0.72% BF) and weight for parents (?1.1 ± 0.91 vs. ?0.60 ± 0.89 kg) did not differ between the behavioral and control programs. Discussion: An internet‐based weight management program for African‐American adolescent girls and their parents resulted in weight loss during the first 6 months but did not yield long‐term loss due to reduced use of the web site over time.