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1.  Relationship of Initial Self-Regulatory Ability with Changes in Self-Regulation and Associated Fruit and Vegetable Consumption in Severely Obese Women Initiating an Exercise and Nutrition Treatment: Moderation of Mood and Self-Efficacy 
An emphasis on increasing self-regulation is an alternate to nutrition education, which has had poor results in the behavioral treatment of obesity. Although appropriately designed weight-loss treatments may enhance one’s self-regulatory ability to control eating, whether improvements are moderated by psychosocial factors such as initial self-regulatory skills use, self-efficacy to control eating, and mood is unknown. Severely obese women (BMI 35-50 kg·m-2) were randomized into 26-week treatments of exercise supported by cognitive-behavioral methods paired with either nutrition education (n = 114) or cognitive-behavioral methods applied to controlled eating (n = 121). Improvement in self-regulation for controlled eating was 36.9% greater (p < 0.01) for the group incorporating cognitive-behavioral methods for controlled eating. Change in self-regulation was significantly associated with self-regulation at baseline (β = -0.33). Both mood and self-efficacy for controlled eating significantly moderated this relationship. Increased self-regulation was associated with both increases in fruit and vegetable consumption and fruit and vegetable intake at treatment end. The present findings increase our understanding of psychosocial variables associated with increased self-regulatory skills usage and improvements in eating that, after replication, may be used to improve the effects of behavioral weight-loss treatments.
Key pointsInitial self-regulatory abilities do not appear to affect improvements in self-regulation for eating, however direct training in behavioral skills are predictors of change.The relationship of self-regulation improvements and improved eating is significant, and affected by mood and self-efficacy in women with obesity.Instruction in behavioral skills such as cognitive restructuring and relapse prevention is associated with better improvements in eating than typical methods of nutrition education.Cognitive-behavioral methods for exercise may be paired with cognitive-behavioral methods for eating to maximize longer-term effects on eating behaviors.
PMCID: PMC3761514  PMID: 24149553
Behavioral treatment; cognitive-behavioral; health psychology; obesity treatment; self-regulation
2.  Behaviorally Supported Exercise Predicts Weight Loss in Obese Adults Through Improvements in Mood, Self-Efficacy, and Self-Regulation, Rather Than by Caloric Expenditure 
The Permanente Journal  2011;15(1):23-27.
Background: The relationship of exercise to weight loss, beyond minimal caloric expenditures possible in obese and deconditioned individuals, requires clarification.
Objective: We assessed whether changes in theory-based psychological variables associated with participation in an exercise treatment extended to psychologically based predictors of controlled eating and weight and waist-circumference reductions.
Methods: A group of 137 adults with severe obesity (mean body mass index, 42.2 kg/m2) volunteered for an exercise-support and nutrition-education treatment of 26 weeks' duration that was based on social cognitive theory. Exercise- and eating-related measures of mood, self-regulation, and self-efficacy were obtained at baseline and at treatment end, along with weight, waist circumference, and exercise volume. Analyses were also conducted separately for women participants only (n = 102).
Results: Treatment-induced changes in total mood disturbance, self-regulatory skill usage for exercise, and exercise self-efficacy were significantly related to changes in self-efficacy to control emotional eating, self-regulatory skill usage for controlled eating, and overall self-efficacy for controlled eating, respectively (p < 0.001). Changes in the eating-related measures significantly predicted changes in weight and waist circumference with adjusted R2 values from 0.15 to 0.21 and 0.28 to 0.30, respectively (p < 0.001). Post-hoc testing indicated a strong negative correlation between exercise completed and weight change (r = −0.62); however, only 12.4% of the observed weight change was accounted for through associated caloric expenditures.
Conclusion: Exercise may support weight loss primarily through psychological rather than physiological pathways. Although the models tested were viable, additional modifiable variables may further strengthen the prediction of weight and waist-circumference change and benefit weight-loss theory and treatment outcomes.
PMCID: PMC3048629  PMID: 21505614
3.  Supported Exercise Improves Controlled Eating and Weight through Its Effects on Psychosocial Factors: Extending a Systematic Research Program Toward Treatment Development 
The Permanente Journal  2012;16(1):7-18.
Background: Behavioral weight-loss treatments have been overwhelmingly unsuccessful. Many inadequately address both behavioral theory and extant research—especially in regard to the lack of viability of simply educating individuals on improved eating and exercise behaviors.
Objective: The aim was to synthesize research on associations of changes in exercise behaviors, psychosocial factors, eating behaviors, and weight; and then conduct further direct testing to inform the development of an improved treatment approach.
Methods: A systematic program of health behavior-change research based on social cognitive theory, and extensions of that theory applied to exercise and weight loss, was first reviewed. Then, to extend this research toward treatment development and application, a field-based study of obese adults was conducted. Treatments incorporated a consistent component of cognitive-behaviorally supported exercise during 26 weeks that was paired with either standard nutrition education (n = 183) or cognitive-behavioral methods for controlled eating that emphasized self-regulatory methods such as goal setting and caloric tracking, cognitive restructuring, and eating cue awareness (n = 247).
Results: Both treatment conditions were associated with improved self-efficacy, self-regulation, mood, exercise, fruit and vegetable consumption, weight, and waist circumference; with improvements in self-regulation for eating, fruit and vegetable consumption, weight, and waist circumference significantly greater in the cognitive-behavioral nutrition condition. Changes in exercise- and eating-related self-efficacy and self-regulation were associated with changes in exercise and eating (R2 = 0.40 and 0.17, respectively), with mood change increasing the explanatory power to R2 = 0.43 and 0.20. Improved self-efficacy and self-regulation for exercise carried over to self-efficacy and self-regulation for controlled eating (β= 0.53 and 0.68, respectively).
Conclusions: Development and longitudinal testing of a new and different approach to behavioral treatment for sustained weight loss that emphasizes exercise program-induced psychosocial changes preceding the facilitation of improved eating and weight loss should be guided by our present research.
PMCID: PMC3327117  PMID: 22529754
4.  From Morbid Obesity to a Healthy Weight Using Cognitive-Behavioral Methods: A Woman's Three-Year Process With One and One-Half Years of Weight Maintenance 
The Permanente Journal  2012;16(4):54-59.
Background: Obesity is a national health problem regularly confronting medical professionals. Although reduced-energy (kilocalorie [kcal]) eating and increased exercise will reliably reduce weight, these behaviors have been highly resistant to sustained change.
Objective: To control eating using theory-based cognitive-behavioral methods that leverage the positive psychosocial effects of newly initiated exercise as an alternate to typical approaches of education about appropriate nutrition.
Method: A woman, age 48 years, with morbid obesity initiated exercise through a 6-month exercise support protocol based on social cognitive and self-efficacy theory (The Coach Approach). This program was followed by periodic individual meetings with a wellness professional intended to transfer behavioral skills learned to adapt to regular exercise, to then control eating. There was consistent recording of exercises completed, foods consumed, various psychosocial and lifestyle factors, and weight.
Results: Over the 4.4 years reported, weight decreased from 117.6 kg to 59.0 kg, and body mass index (BMI) decreased from 43.1 kg/m2 to 21.6 kg/m2. Mean energy intake initially decreased to 1792 kcal/day and further dropped to 1453 kcal/day by the end of the weight-loss phase. Consistent with theory, use of self-regulatory skills, self-efficacy, and overall mood significantly predicted both increased exercise and decreased energy intake. Morbid obesity was reduced to a healthy weight within 3.1 years, and weight was maintained in the healthy range through the present (1.3 years later).
Conclusion: This case supports theory-based propositions that exercise-induced changes in self-regulation, self-efficacy, and mood transfer to and reinforce improvements in corresponding psychosocial factors related to controlled eating.
PMCID: PMC3523938  PMID: 23251120
5.  Reciprocal effects of treatment-induced increases in exercise and improved eating, and their psychosocial correlates, in obese adults seeking weight loss: a field-based trial 
A better understanding of interrelations of exercise and improved eating, and their psychosocial correlates of self-efficacy, mood, and self-regulation, may be useful for the architecture of improved weight loss treatments. Theory-based research within field settings, with samples possessing high probabilities of health risks, might enable rapid application of useful findings.
Adult volunteers with severe obesity (body mass index [BMI] 35–50 kg/m2; age = 43.0 ± 9.5 y; 83% female) were randomly assigned to six monthly cognitive-behavioral exercise support sessions paired with either group-based nutrition education (n = 145) or cognitive behavioral methods applied to improved eating (n = 149). After specification of mediation models using a bias-corrected bootstrapping procedure, a series of reciprocal effects analyses assessed: a) the reciprocal effects of changes in exercise and fruit and vegetable intake, resulting from the treatments, b) the reciprocal effects of changes in the three psychosocial variables tested (i.e. self-efficacy, mood, and self-regulation) and fruit and vegetable change, resulting from change in exercise volume, and c) the reciprocal effects of changes in the three psychosocial variables and exercise change, resulting from change in fruit and vegetable intake.
Mediation analyses suggested a reciprocal effect between changes in exercise volume and fruit and vegetable intake. After inclusion of psychosocial variables, also found were reciprocal effects between change in fruit and vegetable intake and change in mood, self-efficacy for controlled eating, and self-regulation for eating; and change in exercise volume and change in mood and exercise-related self-regulation.
Findings had implications for behavioral weight-loss theory and treatment. Specifically, results suggested that treatments should focus upon, and leverage, the transfer effects from each of the primary weight-loss behaviors (exercise and healthy eating) to the other. Findings on psychosocial correlates of these behavioral processes may also have practical applications.
PMCID: PMC4234203  PMID: 24308572
Exercise; Nutrition; Cognitive-behavioral; Obesity; Reciprocal effects
6.  Relationship of Exercise Volume with Change in Depression and Its Association with Self-Efficacy to Control Emotional Eating in Severely Obese Women 
Introduction. Exercise may improve one's perceived ability to control overeating related to negative emotions through psychological pathways such as reduced depression; however, the volume required is unclear. Methods. Severely obese women (N = 88) participated in a 24-week exercise and nutrition treatment incorporating self-regulatory skills training, and were assessed on depression, self-efficacy, self-regulatory skills usage, weight, and waist circumference, at baseline and treatment end. Results. Subjects completing low-moderate (40–149.9 minutes/week) and public health (≥150 minutes/week) volumes of exercise had significant and similar reductions in depression scores. No significant changes were found for those completing <40 minutes/week. For all subjects aggregated, depression change was significantly related to change in self-efficacy to control emotional eating; however, this relationship was completely mediated by changes in self-regulatory skill usage. When changes in depression, self-efficacy, and self-regulatory skills usage were entered into multiple regression equations as predictors, only self-regulatory skill changes explained significant unique portions of the overall variance in weight and weight circumference change. Discussion. Exercise of less than half the public health recommendation was associated with depression improvement, with no dose-response effect. Changes in depression, self-efficacy, and self-regulation may be salient variables to account for in behavioral weight-loss treatment research.
PMCID: PMC3226245  PMID: 22135751
7.  The family partners for health study: a cluster randomized controlled trial for child and parent weight management 
Nutrition & Diabetes  2014;4(1):e101-.
The purpose of this study was to test a two-phased nutrition and exercise education, coping skills training, and exercise intervention program for overweight or obese low-income ethnic minority 2nd to 4th grade children and their parents in rural North Carolina, USA.
A cluster randomized controlled trial was carried out with 358 children (7–10 years) and a parent for each child (n=358). General linear mixed models were used to determine the effects of the intervention on weight, adiposity, health behaviors, and eating and exercise self-efficacy by examining changes in children and parents from baseline to completion of the study (18 months).
At 18 months, children in the experimental group did not have a significantly decreased body mass index (BMI) percentile (P=0.470); however, they showed a reduction in the growth rate of their triceps (P=0.001) and subscapular skinfolds (P<0.001) and an improvement in dietary knowledge (P=0.018) and drank less than one glass of soda per day (P=0.052) compared with the control group. Parents in the experimental group had decreased BMI (P=0.001), triceps (P<0.001) and subscapular skinfolds (P<0.001) and increased nutrition (P=0.003) and exercise (P<0.001) knowledge and more often drank water or unsweetened drinks (P=0.029). At 18 months, children in the experimental group did not show significant improvement in eating (P=0.956) or exercise self-efficacy (P=0.976). Experimental parents demonstrated improved socially acceptable eating self-efficacy (P=0.013); however, they did not show significant improvement in self-efficacy pertaining to emotional eating (P=0.155) and exercise (P=0.680).
The results suggest that inclusion of children and parents in the same intervention program is an effective way to decrease adiposity and improve nutrition behaviors in both children and parents and improve weight and eating self-efficacy in parents.
PMCID: PMC3904082  PMID: 24418827
overweight; obesity; children; parents; intervention
8.  Weight Loss and Psychologic Gain in Obese Women—Participants in a Supported Exercise Intervention 
The Permanente Journal  2008;12(3):36-45.
Background: Physical activity is a predictor of maintained weight loss; however, causal mechanisms are unclear. Behavioral theories suggest that associated psychologic changes may indirectly affect weight loss.
Objective: We sought to test the association of a behaviorally based exercise support protocol (The Coach Approach [CA]), with and without a group-based nutrition education program (Cultivating Health), with adherence to exercise and changes in physiologic and psychologic factors, and to assess theory-based paths to weight and body-fat changes.
Setting: The study took place in YMCA wellness centers.
Study subjects: Study participation was open to formerly sedentary obese women.
Design: Study participants were randomly assigned to the CA Only (CA; n = 81), The CA Plus Cultivating Health (CA/CH; n = 128), or the control (n = 64) group. We contrasted dropout and attendance rates and changes in self-efficacy (SE), physical self-concept (PSC), total mood disturbance (TMD), body areas satisfaction (BAS), and select physiologic factors during a six-month period. We also analyzed proposed paths to weight loss.
Results: The CA and CA/CH groups had significantly lower exercise dropout rates (χ2 = 44.67, p < 0.001) and higher attendance rates (F = 10.02; p < 0.001) than the control group did. Improvements in body fat, body mass index (BMI), and waist circumference were significant for only the CA and CA/CH groups. Significant improvements in TMD, PSC, and BAS scores were found for all groups, with effect sizes greater in the groups incorporating the CA protocol. Within the five paths assessed, entry of changes in TMD and BAS scores into multiple-regression equations, along with SE and PSC scores, increased the explained variance in exercise session attendance from 5% (p = 0.01) to 16% (p < 0.001). Exercise session attendance was significantly associated with changes in body fat (r = −0.41; p < 0.001) and BMI (r = −0.46; p < 0.001).
Conclusion: Counseling based on social cognitive and self-efficacy theory may increase exercise adherence and improve variables indirectly related to weight and body-fat reductions. Although decreases in body fat and BMI were obtained, they appeared less pronounced than psychologic improvements. Additional research on interrelations of physical activity, psychologic factors, and weight change is warranted for development of obesity treatments.
PMCID: PMC3037122  PMID: 21331208
9.  Engagement in a Diabetes Self-management Website: Usage Patterns and Generalizability of Program Use 
Increased access to the Internet and the availability of efficacious eHealth interventions offer great promise for assisting adults with diabetes to change and maintain health behaviors. A key concern is whether levels of engagement in Internet programs are sufficient to promote and sustain behavior change.
This paper used automated data from an ongoing Internet-based diabetes self-management intervention study to calculate various indices of website engagement. The multimedia website involved goal setting, action planning, and self-monitoring as well as offering features such as “Ask an Expert” to enhance healthy eating, physical activity, and medication adherence. We also investigated participant characteristics associated with website engagement and the relationship between website use and 4-month behavioral and health outcomes.
We report on participants in a randomized controlled trial (RCT) who were randomized to receive (1) the website alone (n = 137) or (2) the website plus human support (n = 133) that included additional phone calls and group meetings. The website was available in English and Spanish and included features to enhance engagement and user experience. A number of engagement variables were calculated for each participant including number of log-ins, number of website components visited at least twice, number of days entering self-monitoring data, number of visits to the “Action Plan” section, and time on the website. Key outcomes included exercise, healthy eating, and medication adherence as well as body mass index (BMI) and biological variables related to cardiovascular disease risk.
Of the 270 intervention participants, the average age was 60, the average BMI was 34.9 kg/m2, 130 (48%) were female, and 62 (23%) self-reported Latino ethnicity. The number of participant visits to the website over 4 months ranged from 1 to 119 (mean 28 visits, median 18). Usage decreased from 70% of participants visiting at least weekly during the first 6 weeks to 47% during weeks 7 to 16. There were no significant differences between website only and website plus support conditions on most of the engagement variables. In total, 75% of participants entered self-monitoring data at least once per week. Exercise action plan pages were visited more often than medication taking and healthy eating pages (mean of 4.3 visits vs 2.8 and 2.0 respectively, P < .001). Spearman nonparametric correlations indicated few significant associations between patient characteristics and summary website engagement variables, and key factors such as ethnicity, baseline computer use, age, health literacy, and education were not related to use. Partial correlations indicated that engagement, especially in self-monitoring, was most consistently related to improvement in healthy eating (r = .20, P = .04) and reduction of dietary fat (r = -.31, P = .001). There was also a significant correlation between self-monitoring and improvement in exercise (r = .20, P = .033) but not with medication taking.
Participants visited the website fairly often and used all of the theoretically important sections, but engagement decreased over 4 months. Usage rates and patterns were similar for a wide range of participants, which has encouraging implications for the potential reach of online interventions.
Trial Registration
NCT00987285; (Archived by WebCite at
PMCID: PMC3221359  PMID: 21371992
Engagement; Internet; diabetes self-management; research methods; health disparities
10.  Weight Gain Prevention: Identifying Theory-Based Targets for Health Behavior Change in Young Adults 
Young adults attending college are more vulnerable to weight gain than the general population. We sought to identify health behavior change targets related to weight management in college students. Based on the social cognitive theory model for health behavior change, we investigated the health-related lifestyle behaviors and physiological characteristics of this population. Forty-three college students (18.3±0.1 years) completed a series of quantitative assessments (body weight and composition, cardiorespiratory fitness, diet and activity habits) and structured qualitative assessments (structured interview or focus group). Participants were predominantly normal-weight (mean BMI=22.2±0.4 kg/m2) and fit (VO2max = 50.5±1.5 ml/kg/min). However, healthy eating and physical activity were not considered high priorities, despite having ample free time, high exercise self-efficacy, positive outcome expectations for exercise, and a desire to exercise more. Participants reported that regularly engaging in exercise was difficult. This may have been due to poor planning/time management, satisfaction with body image, lack of accountability and feelings of laziness. Dietary patterns generally met recommendations but were low in fruits, vegetables and whole grains. Social support for exercise and healthy dietary habits were important factors associated with health behaviors. Students reported a decline in exercise and dietary habits relative to high school, which may contribute to college weight gain. Our results suggest that this population may not have adequate self-regulatory skills, such as planning and self-monitoring, to maintain healthy behaviors in the college environment. Dietitians working with young adults attending college may use these findings to guide the behavioral therapy component of their weight management medical nutrition therapy goals and outcomes.
PMCID: PMC2614557  PMID: 18926139
Weight gain prevention; college weight gain; young adults; behavior change; diet; physical activity; exercise; social cognitive theory
11.  Exploring the Developmental Overnutrition Hypothesis Using Parental–Offspring Associations and FTO as an Instrumental Variable 
PLoS Medicine  2008;5(3):e33.
The developmental overnutrition hypothesis suggests that greater maternal obesity during pregnancy results in increased offspring adiposity in later life. If true, this would result in the obesity epidemic progressing across generations irrespective of environmental or genetic changes. It is therefore important to robustly test this hypothesis.
Methods and Findings
We explored this hypothesis by comparing the associations of maternal and paternal pre-pregnancy body mass index (BMI) with offspring dual energy X-ray absorptiometry (DXA)–determined fat mass measured at 9 to 11 y (4,091 parent–offspring trios) and by using maternal FTO genotype, controlling for offspring FTO genotype, as an instrument for maternal adiposity. Both maternal and paternal BMI were positively associated with offspring fat mass, but the maternal association effect size was larger than that in the paternal association in all models: mean difference in offspring sex- and age-standardised fat mass z-score per 1 standard deviation BMI 0.24 (95% confidence interval [CI]: 0.22 to 0.26) for maternal BMI versus 0.13 (95% CI: 0.11, 0.15) for paternal BMI; p-value for difference in effect < 0.001. The stronger maternal association was robust to sensitivity analyses assuming levels of non-paternity up to 20%. When maternal FTO, controlling for offspring FTO, was used as an instrument for the effect of maternal adiposity, the mean difference in offspring fat mass z-score per 1 standard deviation maternal BMI was −0.08 (95% CI: −0.56 to 0.41), with no strong statistical evidence that this differed from the observational ordinary least squares analyses (p = 0.17).
Neither our parental comparisons nor the use of FTO genotype as an instrumental variable, suggest that greater maternal BMI during offspring development has a marked effect on offspring fat mass at age 9–11 y. Developmental overnutrition related to greater maternal BMI is unlikely to have driven the recent obesity epidemic.
Using parental-offspring associations and theFTO gene as an instrumental variable for maternal adiposity, Debbie Lawlor and colleagues found that greater maternal BMI during offspring development does not appear to have a marked effect on offspring fat mass at age 9-11.
Editors' Summary
Since the 1970s, the proportion of children and adults who are overweight or obese (people who have an unhealthy amount of body fat) has increased sharply in many countries. In the US, 1 in 3 adults is now obese; in the mid-1970s it was only 1 in 7. Similarly, the proportion of overweight children has risen from 1 in 20 to 1 in 5. An adult is considered to be overweight if their body mass index (BMI)—their weight in kilograms divided by their height in meters squared—is between 25 and 30, and obese if it is more than 30. For children, the healthy BMI depends on their age and gender. Compared to people with a healthy weight (a BMI between 18.5 and 25), overweight or obese individuals have an increased lifetime risk of developing diabetes and other adverse health conditions, sometimes becoming ill while they are still young. People become unhealthily fat when they consume food and drink that contains more energy than they need for their daily activities. It should, therefore, be possible to avoid becoming obese by having a healthy diet and exercising regularly.
Why Was This Study Done?
Some researchers think that “developmental overnutrition” may have caused the recent increase in waistline measurements. In other words, if a mother is overweight during pregnancy, high sugar and fat levels in her body might permanently affect her growing baby's appetite control and metabolism, and so her offspring might be at risk of becoming obese in later life. If this hypothesis is true, each generation will tend to be fatter than the previous one and it will be very hard to halt the obesity epidemic simply by encouraging people to eat less and exercise more. In this study, the researchers have used two approaches to test the developmental overnutrition hypothesis. First, they have asked whether offspring fat mass is more strongly related to maternal BMI than to paternal BMI; it should be if the hypothesis is true. Second, they have asked whether a genetic indicator of maternal fatness—the “A” variant of the FTO gene—is related to offspring fat mass. A statistical association between maternal FTO genotype (genetic make-up) and offspring fat mass would support the developmental nutrition hypothesis.
What Did the Researchers Do and Find?
In 1991–1992, the Avon Longitudinal Study of Parents and Children (ALSPAC) enrolled about 14,000 pregnant women and now examines their offspring at regular intervals. The researchers first used statistical methods to look for associations between the self-reported prepregnancy BMI of the parents of about 4,000 children and the children's fat mass at ages 9–11 years measured using a technique called dual energy X-ray absorptiometry. Both maternal and paternal BMI were positively associated with offspring fat mass (that is, fatter parents had fatter children) but the effect of maternal BMI was greater than the effect of paternal BMI. When the researchers examined maternal FTO genotypes and offspring fat mass (after allowing for the offspring's FTO genotype, which would directly affect their fat mass), there was no statistical evidence to suggest that differences in offspring fat mass were related to the maternal FTO genotype.
What Do These Findings Mean?
Although the findings from first approach provide some support for the development overnutrition hypothesis, the effect of maternal BMI on offspring fat mass is too weak to explain the recent obesity epidemic. Developmental overnutrition could, however, be responsible for the much slower increase in obesity that began a century ago. The findings from the second approach provide no support for the developmental overnutrition hypothesis, although these results have wide error margins and need confirming in a larger study. The researchers also note that the effects of developmental overnutrition on offspring fat mass, although weak at age 9–11, might become more important at later ages. Nevertheless, for now, it seems unlikely that developmental overnutrition has been a major driver of the recent obesity epidemic. Interventions that aim to improve people's diet and to increase their physical activity levels could therefore slow or even halt the epidemic.
Additional Information.
Please access these Web sites via the online version of this summary at
See a related PLoS Medicine Perspective article
The MedlinePlus encyclopedia has a page on obesity (in English and Spanish)
The US Centers for Disease Control and Prevention provides information on all aspects of obesity (in English and Spanish)
The UK National Health Service's health Web site (NHS Direct) provides information about obesity
The International Obesity Taskforce provides information about preventing obesity and on childhood obesity
The UK Foods Standards Agency, the United States Department of Agriculture, and Shaping America's Health all provide useful advice about healthy eating for adults and children
The ALSPAC Web site provides information about the Avon Longitudinal Study of Parents and Children and its results so far
PMCID: PMC2265763  PMID: 18336062
12.  The Change in Eating Behaviors in a Web-Based Weight Loss Program: A Longitudinal Analysis of Study Completers 
Eating behaviors are essential components in weight loss programs, but limited research has explored eating behaviors in Web-based weight loss programs.
The aim was to evaluate an interactive Web-based weight loss program on eating behaviors using the 18-item Three-Factor Eating Questionnaire Revised (TFEQ-R18) which measures uncontrolled eating, emotional eating, and cognitive restrained eating. Our Web-based weight loss program is comprised of information about healthy lifestyle choices, weekly chats with experts, social networking features, databases for recipe searches, and features allowing members to self-report and track their weight, physical activity, and dietary intake on the website.
On registering for the weight loss program, 23,333 members agreed to take part in the research study. The participants were then asked to complete the TFEQ-R18 questionnaire at baseline and after 3 and 6 months of participation. All data collection was conducted online, with no face-to-face contact. To study changes in TFEQ-R18 eating behaviors we restricted our study to those members who completed all 3 TFEQ-R18 questionnaires. These participants were defined as “completers” and the remaining as “noncompleters.” The relationships between sex, change in eating behaviors, and total weight loss were studied using repeated measures ANOVA and Pearson correlation coefficient.
In total, 22,800 individuals participated (females: 19,065/22,800, 83.62%; mean age 39.6, SD 11.4 years; BMI 29.0 kg/m2; males: 3735/22,800, 16.38%; mean age 43.2, SD 11.7 years; BMI 30.8 kg/m2). Noncompleters (n=22,180) were younger and reported a lower score of uncontrolled eating and a higher score of cognitive restrained eating. Over time, completers (n=620) decreased their uncontrolled eating score (from 56.3 to 32.0; P<.001) and increased their cognitive restrained eating (from 50.6 to 62.9; P<.001). Males decreased their emotional eating (from 57.2 to 35.9; P<.001), but no significant change was found among females. The baseline cognitive restrained eating score was significantly and positively associated with weight loss for completers in both men (P=.02) and women (P=.002).
To our knowledge, this is the largest TFEQ sample that has been documented. This Web-based weight loss intervention suggests that eating behaviors (cognitive restrained eating, uncontrolled eating, and emotional eating) measured by TFEQ-R18 were significantly changed during 6 months of participation. Our findings indicate differences in eating behaviors with respect to sex, but should be interpreted with caution because attrition was high.
PMCID: PMC4259913  PMID: 25367316
behavior; counseling; diet; eating; method; questionnaires; Internet; weight loss; TFEQ
13.  Eating Behavior and BMI in Adolescent Survivors of Brain Tumor and Acute Lymphoblastic Leukemia 
Elevated BMI has been reported in pediatric cancer survivors. It is unclear whether this is related to altered energy intake (via disordered eating), decreased energy expenditure (via limited exercise), or treatment-related direct/indirect changes. The aims of this study are to describe the occurrence of overweight and obesity, exercise frequency, and the extent of disordered eating patterns in this sample of survivors, and to examine relationships among BMI, eating patterns, exercise frequency and demographic and disease and treatment-related variables to identify those survivors most at risk for overweight/obesity.
This cross-sectional study recruited 98 cancer survivors (50 ALL, 48 Brain Tumor), aged 12-17 years and >12 months post-treatment from a large pediatric oncology hospital. Survivors completed health behavior measures assessing disordered eating patterns and physical activity. Clinical variables were obtained through medical record review. Univariate analyses were conducted to make comparisons on health behaviors by diagnosis, gender, treatment history, and BMI category.
Fifty-two percent of ALL survivors and 41.7% of BT survivors were classified as overweight/obese. Overweight/obesity status was associated with higher Cognitive Restraint (OR=1.0, 95%CI:1.0-1.1). Only 12% of ALL survivors and 8.3% of BT survivors met CDC guidelines for physical activity. Males reported more physical activity (t(96)=2.2, p<.05).
Overweight/obese survivors may attempt to purposefully restrict their food intake and rely less on physiological cues to regulate consumption. Survivors should be screened at follow-up for weight-related concerns.
PMCID: PMC4089040  PMID: 24451908
BMI; disordered eating; physical activity; health behaviors
14.  Effects of 12- and 24-Week Multimodal Interventions on Physical Activity, Nutritional Behaviors, and Body Mass Index and Its Psychological Predictors in Severely Obese Adolescents at Risk for Diabetes 
The Permanente Journal  2010;14(3):29-37.
Background: Although 7% of US adolescents have impaired fasting glucose, a precursor of type 2 diabetes, research has suggested that few interventions for obese adolescents at risk for diabetes have been effective. Therefore, pediatricians seek effective behavioral treatments for referral for this age group.
Objective: We wanted to determine the effects of two different durations of nutritional and exercise treatments on changes in nutrition, physical activity, body mass index (BMI), and psychological predictors of BMI change in overweight and obese adolescents at risk for type 2 diabetes.
Methods: We obtained data from 64 pediatrician-referred patients with diabetes risk factors (mean age, 14.1 years; BMI, ≥99th percentile.) Study participants were assigned to nutrition and exercise treatments for 12 weeks (n = 35) or 24 weeks (n = 29). A specific weight-loss goal was given only for the 24-week group.
Results: Both treatments demonstrated significant within-group changes over 12 weeks in days per week of physical activity of at least 60 minutes, physical self-concept, general self, and overall mood. However, they failed to demonstrate significant 12-week increases in fruit and vegetable intake, decreases in sweetened-beverage consumption, or decreases in BMI. Between-group differences were found only in mood changes in favor of the 12-week treatment. In the 24-week treatment, BMI change from week 12 to week 24 was significantly better than corresponding normative data (d = 0.37). Physical self-concept, general self, and mood scores at week 12 explained a significant portion of the variance in BMI change (R2 = 0.13, p = 0.04).
Conclusion: Nutrition education alone may be insufficient for nutrition behavior change. Behavioral treatment lasting longer than 12 weeks and having a specific weight-loss goal may be useful for BMI improvements, and attention to participants' self-concept and mood may be important treatment considerations.
PMCID: PMC2937842  PMID: 20844702
15.  Bariatric Surgery 
Executive Summary
To conduct an evidence-based analysis of the effectiveness and cost-effectiveness of bariatric surgery.
Obesity is defined as a body mass index (BMI) of at last 30 kg/m2.1 Morbid obesity is defined as a BMI of at least 40 kg/m2 or at least 35 kg/m2 with comorbid conditions. Comorbid conditions associated with obesity include diabetes, hypertension, dyslipidemias, obstructive sleep apnea, weight-related arthropathies, and stress urinary incontinence. It is also associated with depression, and cancers of the breast, uterus, prostate, and colon, and is an independent risk factor for cardiovascular disease.
Obesity is also associated with higher all-cause mortality at any age, even after adjusting for potential confounding factors like smoking. A person with a BMI of 30 kg/m2 has about a 50% higher risk of dying than does someone with a healthy BMI. The risk more than doubles at a BMI of 35 kg/m2. An expert estimated that about 160,000 people are morbidly obese in Ontario. In the United States, the prevalence of morbid obesity is 4.7% (1999–2000).
In Ontario, the 2004 Chief Medical Officer of Health Report said that in 2003, almost one-half of Ontario adults were overweight (BMI 25–29.9 kg/m2) or obese (BMI ≥ 30 kg/m2). About 57% of Ontario men and 42% of Ontario women were overweight or obese. The proportion of the population that was overweight or obese increased gradually from 44% in 1990 to 49% in 2000, and it appears to have stabilized at 49% in 2003. The report also noted that the tendency to be overweight and obese increases with age up to 64 years. BMI should be used cautiously for people aged 65 years and older, because the “normal” range may begin at slightly above 18.5 kg/m2 and extend into the “overweight” range.
The Chief Medical Officer of Health cautioned that these data may underestimate the true extent of the problem, because they were based on self reports, and people tend to over-report their height and under-report their weight. The actual number of Ontario adults who are overweight or obese may be higher.
Diet, exercise, and behavioural therapy are used to help people lose weight. The goals of behavioural therapy are to identify, monitor, and alter behaviour that does not help weight loss. Techniques include self-monitoring of eating habits and physical activity, stress management, stimulus control, problem solving, cognitive restructuring, contingency management, and identifying and using social support. Relapse, when people resume old, unhealthy behaviour and then regain the weight, can be problematic.
Drugs (including gastrointestinal lipase inhibitors, serotonin norepinephrine reuptake inhibitors, and appetite suppressants) may be used if behavioural interventions fail. However, estimates of efficacy may be confounded by high rates of noncompliance, in part owing to the side effects of the drugs. In addition, the drugs have not been approved for indefinite use, despite the chronic nature of obesity.
The Technology
Morbidly obese people may be eligible for bariatric surgery. Bariatric surgery for morbid obesity is considered an intervention of last resort for patients who have attempted first-line forms of medical management, such as diet, increased physical activity, behavioural modification, and drugs.
There are various bariatric surgical procedures and several different variations for each of these procedures. The surgical interventions can be divided into 2 general types: malabsorptive (bypassing parts of the gastrointestinal tract to limit the absorption of food), and restrictive (decreasing the size of the stomach so that the patient is satiated with less food). All of these may be performed as either open surgery or laparoscopically. An example of a malabsorptive technique is Roux-en-Y gastric bypass (RYGB). Examples of restrictive techniques are vertical banded gastroplasty (VBG) and adjustable gastric banding (AGB).
The Ontario Health Insurance Plan (OHIP) Schedule of Benefits for Physician Services includes fee code “S120 gastric bypass or partition, for morbid obesity” as an insured service. The term gastric bypass is a general term that encompasses a variety of surgical methods, all of which involve reconfiguring the digestive system. The term gastric bypass does not include AGB. The number of gastric bypass procedures funded and done in Ontario, and funded as actual out-of-country approvals,2 is shown below.
Number of Gastric Bypass Procedures by Fiscal Year: Ontario and Actual Out-of-Country (OOC) Approvals
Data from Provider Services, MOHLTC
Courtesy of Provider Services, Ministry of Health and Long Term Care
Review Strategy
The Medical Advisory Secretariat reviewed the literature to assess the effectiveness, safety, and cost-effectiveness of bariatric surgery to treat morbid obesity. It used its standard search strategy to retrieve international health technology assessments and English-language journal articles from selected databases. The interventions of interest were bariatric surgery and, for the controls, either optimal conventional management or another type of bariatric procedure. The outcomes of interest were improvement in comorbid conditions (e.g., diabetes, hypertension); short- and long-term weight loss; quality of life; adverse effects; and economic analysis data. The databases yielded 15 international health technology assessments or systematic reviews on bariatric surgery.
Subsequently, the Medical Advisory Secretariat searched MEDLINE and EMBASE from April 2004 to December 2004, after the search cut-off date of April, 2004, for the most recent systematic reviews on bariatric surgery. Ten studies met the inclusion criteria. One of those 10 was the Swedish Obese Subjects study, which started as a registry and intervention study, and then published findings on people who had been enrolled for at least 2 years or at least 10 years. In addition to the literature review of economic analysis data, the Medical Advisory Secretariat also did an Ontario-based economic analysis.
Summary of Findings
Bariatric surgery generally is effective for sustained weight loss of about 16% for people with BMIs of at least 40 kg/m2 or at least 35 kg/m2 with comorbid conditions (including diabetes, high lipid levels, and hypertension). It also is effective at resolving the associated comorbid conditions. This conclusion is largely based on level 3a evidence from the prospectively designed Swedish Obese Subjects study, which recently published 10-year outcomes for patients who had bariatric surgery compared with patients who received nonsurgical treatment. (1)
Regarding specific procedures, there is evidence that malabsorptive techniques are better than other banding techniques for weight loss and resolution of comorbid illnesses. However, there are no published prospective, long-term, direct comparisons of these techniques available.
Surgery for morbid obesity is considered an intervention of last resort for patients who have attempted first-line forms of medical management, such as diet, increased physical activity, behavioural modification, and drugs. In the absence of direct comparisons of active nonsurgical intervention via caloric restriction with bariatric techniques, the following observations are made:
A recent systematic review examining the efficacy of major commercial and organized self-help weight loss programs in the United States concluded that the evidence to support the use of such programs was suboptimal, except for one trial on Weight Watchers. Furthermore, the programs were associated with high costs, attrition rates, and probability of regaining at least 50% of the lost weight in 1 to 2 years. (2)
A recent randomized controlled trial reported 1-year outcomes comparing weight loss and metabolic changes in severely obese patients assigned to either a low-carbohydrate diet or a conventional weight loss diet. At 1 year, weight loss was similar for patients in each group (mean, 2–5 kg). There was a favourable effect on triglyceride levels and glycemic control in the low-carbohydrate diet group. (3)
A decision-analysis model showed bariatric surgery results in increased life expectancy in morbidly obese patients when compared to diet and exercise. (4)
A cost-effectiveness model showed bariatric surgery is cost-effective relative to nonsurgical management. (5)
Extrapolating from 2003 data from the United States, Ontario would likely need to do 3,500 bariatric surgeries per year. It currently does 508 per year, including out-of-country surgeries.
PMCID: PMC3382415  PMID: 23074460
16.  Comparison of a Mindful Eating Intervention to a Diabetes Self-Management Intervention Among Adults With Type 2 Diabetes: A Randomized Controlled Trial 
Mindful eating may be an effective intervention for increasing awareness of hunger and satiety cues, improving eating regulation and dietary patterns, reducing symptoms of depression and anxiety, and promoting weight loss. Diabetes self-management education (DSME), which addresses knowledge, self-efficacy, and outcome expectations for improving food choices, also may be an effective intervention for diabetes self-care. Yet few studies have compared the impact of mindful eating to a DSME-based treatment approach on patient outcomes. Adults 35 to 65 years old with type 2 diabetes for ≥1 year not requiring insulin therapy were recruited from the community and randomly assigned to treatment group. The impact of a group-based 3-month mindful eating intervention (MB-EAT-D; n = 27) to a group-based 3-month DSME “Smart Choices” (SC) intervention (n = 25) postintervention and at 3-month follow-up was evaluated. Repeated-measures ANOVA with contrast analysis compared change in outcomes across time. There was no significant difference between groups in weight change. Significant improvement in depressive symptoms, outcome expectations, nutrition and eating-related self-efficacy, and cognitive control and disinhibition of control regarding eating behaviors occurred for both groups (all p < .0125) at 3-month follow-up. The SC group had greater increase in nutrition knowledge and self-efficacy than the MB-EAT-D group (all p < .05) at 3-month follow-up. MB-EAT-D had significant increase in mindfulness, whereas the SC group had significant increase in fruit and vegetable consumption at study end (all p < .0125). Both SC and MB-EAT-D were effective treatments for diabetes self-management. The availability of mindful eating and DSME-based approaches offers patients greater choices in meeting their self-care needs.
PMCID: PMC4217158  PMID: 23855018
meditation; patient education; randomized controlled trial; type 2 diabetes mellitus
17.  Healthy Weight Regulation and Eating Disorder Prevention in High School Students: A Universal and Targeted Web-Based Intervention 
Given the rising rates of obesity in children and adolescents, developing evidence-based weight loss or weight maintenance interventions that can be widely disseminated, well implemented, and are highly scalable is a public health necessity. Such interventions should ensure that adolescents establish healthy weight regulation practices while also reducing eating disorder risk.
This study describes an online program, StayingFit, which has two tracks for universal and targeted delivery and was designed to enhance healthy living skills, encourage healthy weight regulation, and improve weight/shape concerns among high school adolescents.
Ninth grade students in two high schools in the San Francisco Bay area and in St Louis were invited to participate. Students who were overweight (body mass index [BMI] >85th percentile) were offered the weight management track of StayingFit; students who were normal weight were offered the healthy habits track. The 12-session program included a monitored discussion group and interactive self-monitoring logs. Measures completed pre- and post-intervention included self-report height and weight, used to calculate BMI percentile for age and sex and standardized BMI (zBMI), Youth Risk Behavior Survey (YRBS) nutrition data, the Weight Concerns Scale, and the Center for Epidemiological Studies Depression Scale.
A total of 336 students provided informed consent and were included in the analyses. The racial breakdown of the sample was as follows: 46.7% (157/336) multiracial/other, 31.0% (104/336) Caucasian, 16.7% (56/336) African American, and 5.7% (19/336) did not specify; 43.5% (146/336) of students identified as Hispanic/Latino. BMI percentile and zBMI significantly decreased among students in the weight management track. BMI percentile and zBMI did not significantly change among students in the healthy habits track, demonstrating that these students maintained their weight. Weight/shape concerns significantly decreased among participants in both tracks who had elevated weight/shape concerns at baseline. Fruit and vegetable consumption increased for both tracks. Physical activity increased among participants in the weight management track, while soda consumption and television time decreased.
Results suggest that an Internet-based, universally delivered, targeted intervention may support healthy weight regulation, improve weight/shape concerns among participants with eating disorders risk, and increase physical activity in high school students. Tailored content and interactive features to encourage behavior change may lead to sustainable improvements in adolescent health.
PMCID: PMC3962843  PMID: 24583683
healthy weight regulation; universal and targeted delivery; school-based intervention; prevention; adolescents
18.  Examining the Psychological Pathways to Behavior Change in a Group-Based Lifestyle Program to Prevent Type 2 Diabetes 
Diabetes Care  2012;35(4):699-705.
To examine the psychological process of lifestyle change among adults at risk for type 2 diabetes.
A randomized control trial in which 307 volunteers (intervention, n = 208; wait control, n = 99) diagnosed with prediabetes completed a six-session group-based intervention to promote healthier living. Participants’ motivation to change, diet and exercise self-efficacy, mood, knowledge about diabetes, activity levels, healthy eating, waist circumference, and weight were assessed before and after the program.
Participation in the program was associated with significant increases in healthy eating and physical activity, reductions in waist and weight, and improvements in motivation, positive mood, self-efficacy, and knowledge. Examination of the pathways to lifestyle change showed that the educational aspect of the program increased activity levels because it increased diabetes knowledge and improved mood. Eating behavior was not mediated by any of the psychological variables. Improvements in diet and physical activity were, in turn, directly associated with changes in weight and waist circumference.
Although the program significantly improved motivation, self-efficacy, and mood, its impact on knowledge uniquely explained the increase in physical activity. Group-based programs that are tailored to lifestyle behaviors may provide a cost-effective method of diabetes prevention, but more research is needed to explain why they improve healthy eating.
PMCID: PMC3308314  PMID: 22338102
19.  Body image change and improved eating self-regulation in a weight management intervention in women 
Successful weight management involves the regulation of eating behavior. However, the specific mechanisms underlying its successful regulation remain unclear. This study examined one potential mechanism by testing a model in which improved body image mediated the effects of obesity treatment on eating self-regulation. Further, this study explored the role of different body image components.
Participants were 239 overweight women (age: 37.6 ± 7.1 yr; BMI: 31.5 ± 4.1 kg/m2) engaged in a 12-month behavioral weight management program, which included a body image module. Self-reported measures were used to assess evaluative and investment body image, and eating behavior. Measurements occurred at baseline and at 12 months. Baseline-residualized scores were calculated to report change in the dependent variables. The model was tested using partial least squares analysis.
The model explained 18-44% of the variance in the dependent variables. Treatment significantly improved both body image components, particularly by decreasing its investment component (f2 = .32 vs. f2 = .22). Eating behavior was positively predicted by investment body image change (p < .001) and to a lesser extent by evaluative body image (p < .05). Treatment had significant effects on 12-month eating behavior change, which were fully mediated by investment and partially mediated by evaluative body image (effect ratios: .68 and .22, respectively).
Results suggest that improving body image, particularly by reducing its salience in one's personal life, might play a role in enhancing eating self-regulation during weight control. Accordingly, future weight loss interventions could benefit from proactively addressing body image-related issues as part of their protocols.
PMCID: PMC3150233  PMID: 21767360
Body image; Eating Self-regulation; Eating behavior; Weight Management; Obesity
20.  Arthritis Self-Efficacy and Self-Efficacy for Resisting Eating: Relationships to Pain, Disability, and Eating Behavior in Overweight and Obese Individuals with Osteoarthritic Knee Pain 
Pain  2007;136(3):340-347.
This study examined arthritis self-efficacy and self-efficacy for resisting eating as predictors of pain, disability, and eating behaviors in overweight or obese patients with osteoarthritis (OA) of the knee. Patients (N=174) with a body mass index between 25 and 42 completed measures of arthritis-related self-efficacy, weight-related self-efficacy, pain, physical disability, psychological disability, overeating, and demographic and medical information. Hierarchical linear regression analyses were conducted to examine whether arthritis self-efficacy (efficacy for pain control, physical function, and other symptoms) and self-efficacy for resisting eating accounted for significant variance in pain, disability, and eating behaviors after controlling for demographic and medical characteristics. Analyses also tested whether the contributions of self-efficacy were domain specific. Results showed that self-efficacy for pain accounted for 14% (p=.01) of the variance in pain, compared to only 3% accounted for by self-efficacy for physical function and other symptoms. Self-efficacy for physical function accounted for 10% (p=.001) of the variance in physical disability, while self-efficacy for pain and other symptoms accounted for 3%. Self-efficacy for other (emotional) symptoms and resisting eating accounted for 21% (p<.05) of the variance in psychological disability, while self-efficacy for pain control and physical function were not significant predictors. Self-efficacy for resisting eating accounted for 28% (p=.001) of the variance in eating behaviors. Findings indicate that self-efficacy is important in understanding pain and behavioral adjustment in overweight or obese OA patients. Moreover, the contributions of self-efficacy were domain specific. Interventions targeting both arthritis self-efficacy and self-efficacy for resisting eating may be helpful in this population.
PMCID: PMC2494734  PMID: 17764844
21.  Are Eating Disorder Prevention Programs Effective 
Journal of Athletic Training  2009;44(3):304-305.
Reference Citation:
Cororve Fingeret M, Warren CS, Cepeda-Benito A, Gleaves DH. Eating disorder prevention research: a meta-analysis. Eat Disord. 2006;14(3):191–213.
Clinical Questions:
(1) Does presenting educational material on eating disorders produce iatrogenic (harmful because of the intervention) effects on eating attitudes and behaviors? (2) Is targeting specific populations with eating disorder prevention more beneficial than targeting general populations? (3) Which outcome variables are most affected by intervention efforts? (4) To what degree can interventions effectively influence behavioral outcome variables?
Data Sources:
Studies included in the meta-analysis were found using PsycInfo, Web of Science, Dissertation Abstracts International, and ERIC. Studies were also located using the reference lists from searched articles and by contacting researchers in the field for unpublished studies. The search terms used were eating disorders, prevention, intervention, eating, attitudes, and behaviors. These terms were used in various combinations in the search to find appropriate articles.
Study Selection:
Only empirical studies that tested interventions focused on reducing the risk of eating disorders or improving protective factors were included. These studies also had to include a nonclinical sample and a comparison group. Any studies that did not report data for a control group, did not report SDs, or only presented adjusted means were excluded because data were insufficient to determine an effect size. As a result of the small number of studies with male participants and the difference in eating disorder risk between males and females, only studies with female participants were analyzed.
Data Extraction:
Because of the different clinical questions addressed, each study had specific features that were coded to ease data comparison among studies. Three categories of features were coded: population targeted, length of intervention and follow-up, and intervention strategies. To code for the targeted population, the Gordon (1983) classification system was used, including universal (normal), selective (at-risk), and indicated (symptomatic) populations.
The intervention strategies used in each study were also categorized in the meta-analysis. One category of intervention strategies looked at the amount of information related to eating disorders included in the prevention program. In addition, the authors categorized the intervention strategies as being (1) purely educational, (2) enhanced educational with elements of cognitive-behavioral therapy, or (3) purely interactive cognitive-behavioral therapy with no educational component. The first 2 authors rated and coded the studies independently. Standardized mean difference effect size (d) was calculated from reported means and SDs or was estimated from reported t and F values. Statistics were analyzed using DSTAT 1.10 and Comprehensive Meta-Analysis software programs. Data were analyzed based on the outcome variables of knowledge, general eating abnormalities, dieting, body dissatisfaction, and thin-ideal internalization. These outcome variables were used to evaluate the efficacy of the intervention programs. Each outcome set had weighted mean effect sizes determined, and the variability of the effect sizes was assessed using the homogeneity statistic Q. These were calculated for both the posttest and follow-up results. Homogeneity among effect sizes was the desired outcome, and a positive value indicated a more desirable outcome. The effect sizes were described as small (d ≤ .20), medium (d  =  .50), or large (d ≥ .80).
Main Results:
A total of 57 studies were identified by the search criteria. Eleven studies were excluded because they provided insufficient data to calculate effect sizes. The final pool included 46 studies (32 published and 14 unpublished). All eating disorder prevention programs produced the largest positive change in participant knowledge (d  =  .75) without regard to the targeted population. The biggest gains in knowledge occurred right after completion of the prevention program (d  =  1.2). During follow-up, the gains in knowledge decreased but still remained higher than knowledge before the program. General eating abnormalities, dieting, and thin-ideal internalization showed small positive changes. Even though the changes were relatively small at posttest for all the outcomes (d  =  .17 to .21), they seemed to last, because the follow-up studies showed results very similar to those obtained at posttest (d  =  .13 to .18). Body dissatisfaction was the most frequently measured outcome but had the smallest change. Effect sizes for body dissatisfaction at posttest (d  =  .13) and at follow-up (d  =  .07) were not different from zero (95% confidence interval  =  −0.02, 0.15). Thus, even though small positive trends were noted in participants' body dissatisfaction after the interventions, the measured changes may have been due to measurement error. All outcome variables measured appeared to show improvements; however, most of the effect sizes were small and may not be clinically significant. All outcome variables were also analyzed while comparing the targeted populations. During posttest measurements, targeted at-risk participant groups had more positive scores related to dieting (d  =  .28) than did the symptomatic (d  =  .07) and normal (d  =  −.01) groups. Targeted, symptomatic participant groups showed greater improvement regarding thin-ideal internalization during the posttest (d  =  .48) than did the at-risk (d  =  .13) or normal (d  =  .18) subgroups. At follow-up, the same positive trend was apparent, but the changes were no longer significant. Comparably, the targeted, symptomatic group also showed greater improvement with regard to body dissatisfaction (d  =  .30) than did the at-risk (d  =  .11) and normal (d  =  .08) subgroups during posttest measurements, yet the results were not significant at follow-up. General positive trends were found regarding participant knowledge for symptomatic, at-risk, and normal subgroups, but because of the wide range of results among studies, no decisive interpretations could be made. The third measured variable was intervention strategy used. No differences were noted between educational and enhanced educational interventions concerning dieting behavior at posttest, thin-ideal internalization at posttest, or body dissatisfaction at posttest or follow-up. No differences were found among groups for the outcome sets related to potential harmful effects resulting from the prevention programs. From these findings, the authors determined that no harmful effects occurred as a result of including educational information about eating disorders in an eating disorder prevention program.
Currently, evidence supports the potential benefits of eating disorder prevention programs for targeted populations, specifically those already demonstrating signs of an eating disorder. Eating disorder prevention programs seem to increase participants' knowledge of eating disorders. Limited evidence indicates small improvements on the behavioral outcome variables, dieting behaviors, and general eating abnormalities for a range of population groups. Knowledge is the outcome variable most affected by eating disorder prevention programs. No evidence indicating that providing educational information about eating disorders causes potentially harmful effects on attitudes or behaviors was found. Specific symptoms that signal an eating disorder were excluded from research assessments, so accurate conclusions regarding the actual prevention of eating disorders resulting directly from eating disorder prevention programs cannot be made.
PMCID: PMC2681220  PMID: 19478846
dieting; nutrition; education
22.  Causal Relationship between Obesity and Vitamin D Status: Bi-Directional Mendelian Randomization Analysis of Multiple Cohorts 
PLoS Medicine  2013;10(2):e1001383.
A mendelian randomization study based on data from multiple cohorts conducted by Karani Santhanakrishnan Vimaleswaran and colleagues re-examines the causal nature of the relationship between vitamin D levels and obesity.
Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI) and 25-hydroxyvitamin D [25(OH)D] using genetic markers as instrumental variables (IVs) in bi-directional Mendelian randomization (MR) analysis.
Methods and Findings
We used information from 21 adult cohorts (up to 42,024 participants) with 12 BMI-related SNPs (combined in an allelic score) to produce an instrument for BMI and four SNPs associated with 25(OH)D (combined in two allelic scores, separately for genes encoding its synthesis or metabolism) as an instrument for vitamin D. Regression estimates for the IVs (allele scores) were generated within-study and pooled by meta-analysis to generate summary effects.
Associations between vitamin D scores and BMI were confirmed in the Genetic Investigation of Anthropometric Traits (GIANT) consortium (n = 123,864). Each 1 kg/m2 higher BMI was associated with 1.15% lower 25(OH)D (p = 6.52×10−27). The BMI allele score was associated both with BMI (p = 6.30×10−62) and 25(OH)D (−0.06% [95% CI −0.10 to −0.02], p = 0.004) in the cohorts that underwent meta-analysis. The two vitamin D allele scores were strongly associated with 25(OH)D (p≤8.07×10−57 for both scores) but not with BMI (synthesis score, p = 0.88; metabolism score, p = 0.08) in the meta-analysis. A 10% higher genetically instrumented BMI was associated with 4.2% lower 25(OH)D concentrations (IV ratio: −4.2 [95% CI −7.1 to −1.3], p = 0.005). No association was seen for genetically instrumented 25(OH)D with BMI, a finding that was confirmed using data from the GIANT consortium (p≥0.57 for both vitamin D scores).
On the basis of a bi-directional genetic approach that limits confounding, our study suggests that a higher BMI leads to lower 25(OH)D, while any effects of lower 25(OH)D increasing BMI are likely to be small. Population level interventions to reduce BMI are expected to decrease the prevalence of vitamin D deficiency.
Please see later in the article for the Editors' Summary
Editors' Summary
Obesity—having an unhealthy amount of body fat—is increasing worldwide. In the US, for example, a third of the adult population is now obese. Obesity is defined as having a body mass index (BMI, an indicator of body fat calculated by dividing a person's weight in kilograms by their height in meters squared) of more than 30.0 kg/m2. Although there is a genetic contribution to obesity, people generally become obese by consuming food and drink that contains more energy than they need for their daily activities. Thus, obesity can be prevented by having a healthy diet and exercising regularly. Compared to people with a healthy weight, obese individuals have an increased risk of developing diabetes, heart disease and stroke, and tend to die younger. They also have a higher risk of vitamin D deficiency, another increasingly common public health concern. Vitamin D, which is essential for healthy bones as well as other functions, is made in the skin after exposure to sunlight but can also be obtained through the diet and through supplements.
Why Was This Study Done?
Observational studies cannot prove that obesity causes vitamin D deficiency because obese individuals may share other characteristics that reduce their circulating 25-hydroxy vitamin D [25(OH)D] levels (referred to as confounding). Moreover, observational studies cannot indicate whether the larger vitamin D storage capacity of obese individuals (vitamin D is stored in fatty tissues) lowers their 25(OH)D levels or whether 25(OH)D levels influence fat accumulation (reverse causation). If obesity causes vitamin D deficiency, monitoring and treating vitamin D deficiency might alleviate some of the adverse health effects of obesity. Conversely, if low vitamin D levels cause obesity, encouraging people to take vitamin D supplements might help to control the obesity epidemic. Here, the researchers use bi-directional “Mendelian randomization” to examine the direction and causality of the relationship between BMI and 25(OH)D. In Mendelian randomization, causality is inferred from associations between genetic variants that mimic the influence of a modifiable environmental exposure and the outcome of interest. Because gene variants do not change over time and are inherited randomly, they are not prone to confounding and are free from reverse causation. Thus, if a lower vitamin D status leads to obesity, genetic variants associated with lower 25(OH)D concentrations should be associated with higher BMI, and if obesity leads to a lower vitamin D status, then genetic variants associated with higher BMI should be associated with lower 25(OH)D concentrations.
What Did the Researchers Do and Find?
The researchers created a “BMI allele score” based on 12 BMI-related gene variants and two “25(OH)D allele scores,” which are based on gene variants that affect either 25(OH)D synthesis or breakdown. Using information on up to 42,024 participants from 21 studies, the researchers showed that the BMI allele score was associated with both BMI and with 25(OH)D levels among the study participants. Based on this information, they calculated that each 10% increase in BMI will lead to a 4.2% decrease in 25(OH)D concentrations. By contrast, although both 25(OH)D allele scores were strongly associated with 25(OH)D levels, neither score was associated with BMI. This lack of an association between 25(OH)D allele scores and obesity was confirmed using data from more than 100,000 individuals involved in 46 studies that has been collected by the GIANT (Genetic Investigation of Anthropometric Traits) consortium.
What Do These Findings Mean?
These findings suggest that a higher BMI leads to a lower vitamin D status whereas any effects of low vitamin D status on BMI are likely to be small. That is, these findings provide evidence for obesity as a causal factor in the development of vitamin D deficiency but not for vitamin D deficiency as a causal factor in the development of obesity. These findings suggest that population-level interventions to reduce obesity should lead to a reduction in the prevalence of vitamin D deficiency and highlight the importance of monitoring and treating vitamin D deficiency as a means of alleviating the adverse influences of obesity on health.
Additional Information
Please access these Web sites via the online version of this summary at
The US Centers for Disease Control and Prevention provides information on all aspects of overweight and obesity (in English and Spanish); a data brief provides information about the vitamin D status of the US population
The World Health Organization provides information on obesity (in several languages)
The UK National Health Service Choices website provides detailed information about obesity and a link to a personal story about losing weight; it also provides information about vitamin D
The International Obesity Taskforce provides information about the global obesity epidemic
The US Department of Agriculture's website provides a personal healthy eating plan; the Weight-control Information Network is an information service provided for the general public and health professionals by the US National Institute of Diabetes and Digestive and Kidney Diseases (in English and Spanish)
The US Office of Dietary Supplements provides information about vitamin D (in English and Spanish)
MedlinePlus has links to further information about obesity and about vitamin D (in English and Spanish)
Wikipedia has a page on Mendelian randomization (note: Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
Overview and details of the collaborative large-scale genetic association study (D-CarDia) provide information about vitamin D and the risk of cardiovascular disease, diabetes and related traits
PMCID: PMC3564800  PMID: 23393431
23.  Rationale, design, methodology and sample characteristics for the family partners for health study: a cluster randomized controlled study 
BMC Public Health  2012;12:250.
Young children who are overweight are at increased risk of becoming obese and developing type 2 diabetes and cardiovascular disease later in life. Therefore, early intervention is critical. This paper describes the rationale, design, methodology, and sample characteristics of a 5-year cluster randomized controlled trial being conducted in eight elementary schools in rural North Carolina, United States.
The first aim of the trial is to examine the effects of a two-phased intervention on weight status, adiposity, nutrition and exercise health behaviors, and self-efficacy in overweight or obese 2nd, 3 rd, and 4th grade children and their overweight or obese parents. The primary outcome in children is stabilization of BMI percentile trajectory from baseline to 18 months. The primary outcome in parents is a decrease in BMI from baseline to 18 months. Secondary outcomes for both children and parents include adiposity, nutrition and exercise health behaviors, and self-efficacy from baseline to 18 months. A secondary aim of the trial is to examine in the experimental group, the relationships between parents and children's changes in weight status, adiposity, nutrition and exercise health behaviors, and self-efficacy. An exploratory aim is to determine whether African American, Hispanic, and non-Hispanic white children and parents in the experimental group benefit differently from the intervention in weight status, adiposity, health behaviors, and self-efficacy.
A total of 358 African American, non-Hispanic white, and bilingual Hispanic children with a BMI ≥ 85th percentile and 358 parents with a BMI ≥ 25 kg/m2 have been inducted over 3 1/2 years and randomized by cohort to either an experimental or a wait-listed control group. The experimental group receives a 12-week intensive intervention of nutrition and exercise education, coping skills training and exercise (Phase I), 9 months of continued monthly contact (Phase II) and then 6 months (follow-up) on their own. Safety endpoints include adverse event reporting. Intention-to-treat analysis will be applied to all data.
Findings from this trial may lead to an effective intervention to assist children and parents to work together to improve nutrition and exercise patterns by making small lifestyle pattern changes.
Trial registration
PMCID: PMC3353192  PMID: 22463125
24.  Weight Loss Following a Clinic-Based Weight Loss Program Among Adults with Attention Deficit/Hyperactivity Disorder Symptoms 
Eating and weight disorders : EWD  2010;15(3):e166-e172.
The purpose of the present study was to compare obese patients screening positive or negative for attention deficit/hyperactivity disorder (ADHD) on pre-treatment body mass index (BMI), weight loss following a 16 week clinic-based behavioral weight loss program, weight loss attempts, dietary and physical activity habits, perceived difficulty of weight control skills, and eating self-efficacy.
Patients who completed a behavioral weight loss program were approached to complete questionnaires on ADHD and eating habits. Medical charts were reviewed to obtain weight at pre- and post-treatment.
Participants (N=63) were 75% female, mean age was 49 (standard deviation = 10.3), mean body mass index (BMI) was 41.4 kg/m2(standard deviation = 6.8) and 30% screened positive for ADHD on the Adult ADHD Symptom Rating Scale. Participants screening positive for ADHD did not have a higher BMI at baseline (p =.41), but reported more previous weight loss attempts (p=.01) and lost less weight (p= .02) than participants who screened negative. Participants screening positive also reported consuming fast food meals more frequently (p=.04), higher levels of emotional eating (p=.002), greater difficulty with weight control skills (p=.01), and lower eating self-efficacy (p=.001).
Attention-related problems appear to be common among weight treatment-seeking samples and represent a significant barrier to weight control that has not yet been addressed in the literature.
PMCID: PMC3211042  PMID: 21150252
attention deficit hyperactivity disorder; obesity; weight loss; adults; weight behaviors
25.  Obesity and eating habits among college students in Saudi Arabia: a cross sectional study 
Nutrition Journal  2010;9:39.
During the last few decades, the Kingdom of Saudi Arabia (KSA) experienced rapid socio-cultural changes caused by the accelerating economy in the Arabian Gulf region. That was associated with major changes in the food choices and eating habits which, progressively, became more and more "Westernized". Such "a nutritional transition" has been claimed for the rising rates of overweight and obesity which were recently observed among Saudi population. Therefore, the objectives of the current work were to 1) determine the prevalence of overweight and obesity in a sample of male college students in KSA and 2) determine the relationship between the students' body weight status and composition and their eating habits.
A total of 357 male students aged 18-24 years were randomly chosen from College of Health Sciences at Rass, Qassim University, KSA for the present study. A Self-reported questionnaire about the students' eating habits was conducted, and their body mass index (BMI), body fat percent (BF%), and visceral fat level (VFL) were measured. Data were analyzed using SPSS statistical software, and the Chi-square test was conducted for variables.
The current data indicated that 21.8% of the students were overweight and 15.7% were obese. The total body fat exceeded its normal limits in 55.2% of the participants and VFL was high in 21.8% of them. The most common eating habits encountered were eating with family, having two meals per day including breakfast, together with frequent snacks and fried food consumption. Vegetables and fruits, except dates, were not frequently consumed by most students. Statistically, significant direct correlations were found among BMI, BF% and VFL (P < 0.001). Both BMI and VFL had significant inverse correlation with the frequency of eating with family (P = 0.005 and 0.007 respectively). Similar correlations were also found between BMI and snacks consumption rate (P = 0.018), as well as, between VFL and the frequency of eating dates (P = 0.013).
Our findings suggest the need for strategies and coordinated efforts at all levels to reduce the tendency of overweight, obesity and elevated body fat, and to promote healthy eating habits in our youth.
PMCID: PMC2949783  PMID: 20849655

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