Differences in Weight Loss Across Different BMI Classes:A Meta-analysis of the Effects of Interventions with Diet and Exercise

A Motivational Technology Perspective on the Use of Smart Wrist-Worn Wearables for Postpartum Exercise and Weight Management

Exercise and weight management is crucial in preventing postpartum depression and long-term obesity that carries the risk of chronic illness among postpartum women. Although communication devices, such as a smart wrist-worn wearable (SWW), can help users be more physically active, the extent to which postpartum women might benefit from this technology is unknown. We examined how SWWs promoted exercise and helped postpartum women return to pre-pregnancy weight. We tested a model based on the premise that a motivational device that prompts users to engage with it can establish healthy daily routines. An online survey of 309 postpartum women who were living in the United States and were current users of SWWs revealed that the device encouraged them to spend time completing workout goals. Technological affordances (i.e. customization, navigability, and interactivity) and subsequent user engagement with the device positively predicted total workout hours among postpartum women. We present practical implications for postpartum care programs and smart wearable developers.

Physical Activity, Sedentary Behavior, and Pancreatic Cancer Risk: A Mendelian Randomization Study

Pancreatic cancer is currently the seventh leading cause of cancer death worldwide. Understanding whether modifiable factors increase or decrease the risk of this disease is central to facilitating primary prevention. Several epidemiological studies have described the benefits of physical activity, and the risks associated with sedentary behavior, in relation to cancer. This study aimed to assess evidence of causal effects of physical activity and sedentary behavior on pancreatic cancer risk. We conducted a two-sample Mendelian randomization study using publicly available data for genetic variants associated with physical activity and sedentary behavior traits and genetic data from the Pancreatic Cancer Cohort Consortium (PanScan), the Pancreatic Cancer Case-Control Consortium (PanC4), and the FinnGen study for a total of 10 018 pancreatic cancer cases and 266 638 controls. We also investigated the role of body mass index (BMI) as a possible mediator between physical activity and sedentary traits and risk of developing pancreatic cancer. We found evidence of a causal association between genetically determined hours spent watching television (hours per day) and increased risk of pancreatic cancer for each hour increment (PanScan-PanC4 odds ratio = 1.52, 95% confidence interval 1.17-1.98, P = .002). Additionally, mediation analysis showed that genetically determined television-watching time was strongly associated with BMI, and the estimated proportion of the effect of television-watching time on pancreatic cancer risk mediated by BMI was 54%. This study reports the first Mendelian randomization-based evidence of a causal association between a measure of sedentary behavior (television-watching time) and risk of pancreatic cancer and that this is strongly mediated by BMI. Summary: Pancreatic cancer is a deadly disease that is predicted to become the second leading cause of cancer-related deaths by 2030. Physical activity and sedentary behaviors have been linked to cancer risk and survival. However, there is limited research on their correlation with pancreatic cancer. To investigate this, we used a Mendelian randomization approach to examine the genetic predisposition to physical activity and sedentariness and their relation to pancreatic cancer risk, while excluding external confounders. Our findings revealed a causal link between the time spent watching television and an increased risk of pancreatic cancer. Additionally, we determined that over half of the effect of watching television on pancreatic risk is mediated by the individual's BMI.

Behavioural strategies to reduce obesity among lower socio-economic adults living in high-income countries: a Grades of Recommendation, Assessment, Development and Evaluation-assessed systematic review and meta-analysis of randomised controlled trials

Adult obesity disproportionately affects lower socio-economic groups in high-income countries and perpetuates health inequalities, imposing health and socio-economic burden. This review evaluates the effectiveness of behavioural strategies in reducing weight and cardiovascular disease (CVD) risks among low-income groups based in high-income countries. We searched major databases for randomised controlled trials published between 1 November 2011 and 1 May 2023. Meta-analyses and subgroup analyses were undertaken to analyse the pooled and individual effects of behavioural strategies. Cochrane Risk of bias (RoB 2·0) tool and Grades of Recommendation, Assessment, Development and Evaluation (GRADE) criteria were used to assess the quality and certainty of evidence. Fourteen trials (3618 adults, aged 40·2 ± 9·7 years with BMI 33·6 ± 2·8 kg/m2) and nine unique interventions were identified. Three trials with high RoB were omitted. Meta-analysis favoured interventions, demonstrating significant reductions in body weight (MD: -1·56 kg, (95 % CI -2·09, -1·03)) and HbA1c (MD: -0·05 %, (95 % CI - 0·10, -0·001)) at intervention end. Sub-group analysis showed no differences in waist circumference, blood pressure or serum lipids. Financial incentives and interactive feedback produced greatest amounts of weight losses ≥ 2 kg (GRADE: moderate). Behavioural strategies are effective weight loss interventions among lower socio-economic groups living in high-income nations. However, the impact on CVD risk remains unclear.

Physiology of sedentary behavior

Sedentary behaviors (SB) are characterized by low energy expenditure while in a sitting or reclining posture. Evidence relevant to understanding the physiology of SB can be derived from studies employing several experimental models: bed rest, immobilization, reduced step count, and reducing/interrupting prolonged SB. We examine the relevant physiological evidence relating to body weight and energy balance, intermediary metabolism, cardiovascular and respiratory systems, the musculoskeletal system, the central nervous system, and immunity and inflammatory responses. Excessive and prolonged SB can lead to insulin resistance, vascular dysfunction, shift in substrate use toward carbohydrate oxidation, shift in muscle fiber from oxidative to glycolytic type, reduced cardiorespiratory fitness, loss of muscle mass and strength and bone mass, and increased total body fat mass and visceral fat depot, blood lipid concentrations, and inflammation. Despite marked differences across individual studies, longer term interventions aimed at reducing/interrupting SB have resulted in small, albeit marginally clinically meaningful, benefits on body weight, waist circumference, percent body fat, fasting glucose, insulin, HbA1c and HDL concentrations, systolic blood pressure, and vascular function in adults and older adults. There is more limited evidence for other health-related outcomes and physiological systems and for children and adolescents. Future research should focus on the investigation of molecular and cellular mechanisms underpinning adaptations to increasing and reducing/interrupting SB and the necessary changes in SB and physical activity to impact physiological systems and overall health in diverse population groups.

Weight loss in a digital app-based diabetes prevention program powered by artificial intelligence

Objective

The National Diabetes Prevention Program (DPP) reduces diabetes incidence and associated medical costs but is typically staffing-intensive, limiting scalability. We evaluated an alternative delivery method with 3933 members of a program powered by conversational Artificial Intelligence (AI) called Lark DPP that has full recognition from the Centers for Disease Control and Prevention (CDC).

Methods

We compared weight loss maintenance at 12 months between two groups: 1) CDC qualifiers who completed ≥4 educational lessons over 9 months (n  =  191) and 2) non-qualifiers who did not complete the required CDC lessons but provided weigh-ins at 12 months (n  =  223). For a secondary aim, we removed the requirement for a 12-month weight and used logistic regression to investigate predictors of weight nadir in 3148 members.

Results

CDC qualifiers maintained greater weight loss at 12 months than non-qualifiers (M  =  5.3%, SE  =  .8 vs. M  =  3.3%, SE  =  .8; p  =  .015), with 40% achieving ≥5%. The weight nadir of 3148 members was 4.2% (SE  =  .1), with 35% achieving ≥5%. Male sex (β = .11; P  =  .009), weeks with ≥2 weigh-ins (β = .68; P < .0001), and days with an AI-powered coaching exchange (β = .43; P < .0001) were associated with a greater likelihood of achieving ≥5% weight loss.

Conclusions

An AI-powered DPP facilitated weight loss and maintenance commensurate with outcomes of other digital and in-person programs not powered by AI. Beyond CDC lesson completion, engaging with AI coaching and frequent weighing increased the likelihood of achieving ≥5% weight loss. An AI-powered program is an effective method to deliver the DPP in a scalable, resource-efficient manner to keep pace with the prediabetes epidemic.

Effectiveness of a 12-Month Online Weight Reduction Program in Cohorts with Different Baseline BMI-A Prospective Cohort Study

The purpose of this article was to answer the question of whether people who want to reduce their body weight can achieve different results depending on their baseline BMI and whether the rate of weight loss is constant over the months of intervention. The study included 400 individuals aged 19 to 55 years with a mean BMI of 31.83 ± 4.77 (min 25.1 max 51.8). Men comprised 190 subjects and women 210 subjects. The participants were divided into three groups with the following BMI: overweight, class 1 obesity, and obesity class > 1 (class 2 and 3 combined). BMI groups were randomized by gender, the number of trainings per week, training time, intervention length, and intervention type. The online intervention consisted of a 15% energy deficit diet and training. Over the 12-month dietary intervention, overweight subjects reduced average body weight by 16.6%. The group with class 1 obesity reduced body weight by 15.7%. The group with obesity class > 1 reduced mean body weight by 15.4%. The relative weight reduction in the overweight group was significantly greater than in the other obesity groups (p = 0.007). In all groups, the rate of weight loss from month-to-month was statistically significant (p = 0.0001), ranging between 0.6 and 2.6% per month. The results indicate that overweight individuals are likely to experience a percent greater weight loss as a result of a comprehensive lifestyle intervention. Regardless of baseline BMI, the observed weight loss was consistent from month-to-month throughout the 12-month period, which may indicate that the diet, as well as, the training plan were properly tailored to the subjects’ needs and that they were highly motivated to participate in the program throughout its course. Properly conducted lifestyle intervention enables significant weight loss regardless of baseline BMI values.

Weight Gain after Hormone Receptor-Positive Breast Cancer

Obesity following breast cancer diagnosis is associated with poor overall survival. Understanding weight trajectories will help inform breast cancer survivors at greater risk of weight gain, and those who would benefit from earlier anti-obesity interventions. We performed a retrospective chart review of women from the Breast Cancer Program Longitudinal Repository (BCPLR) at Johns Hopkins diagnosed with hormone receptor-positive Stage I-III breast cancer from 2010 to 2020. We investigated obesity (measured by body mass index [BMI]) over time, patient and tumor characteristics, as well as treatment and recurrence. We observed a significant ≥5% increase in BMI from diagnosis to most recent follow-up (p = 0.009), particularly among those who were overweight at diagnosis (p = 0.003). Additionally, among those up to 5 years since diagnosis, there was a significant association between experiencing a ≥0.1 kg/m² increase per year since diagnosis and baseline BMI status (p = 0.009). A ≥0.6 kg/m² decrease in BMI was observed for participants with obesity at diagnosis (p = 0.006). Our study highlights (i) the significant burden of obesity in women with a history of breast cancer and (ii) higher risks for increases in BMI and shifts in class of obesity among women who are overweight at diagnosis.

Pharmacological profile of once-weekly injectable semaglutide for chronic weight management

INTRODUCTION

The recent approval in the USA (Food and Drug Administration), Canada (Health Canada), UK (Medicines and Healthcare products Regulatory Agency), and EU (European Medicines Agency) of once-weekly injectable semaglutide 2.4 mg, as an adjunct to a calorie-controlled diet and increased physical activity, for chronic weight management provides health-care practitioners with an additional option when prescribing weight-loss medication.

AREAS COVERED

We describe the chemistry, mechanism of action, and pharmacological properties of semaglutide (a glucagon-like peptide 1 receptor agonist [GLP-1 RA]) and discuss clinical data and considerations for using once-weekly subcutaneous semaglutide 2.4 mg as treatment for overweight and obesity among patients with and without type 2 diabetes (T2D).

EXPERT OPINION

Once-weekly subcutaneous semaglutide 2.4 mg is the most efficacious medication approved for chronic weight management among patients with overweight and obesity, with and without T2D, and is the first drug to induce sustained double-digit reductions in percentage body weight over 1- to 2-year treatment periods. It demonstrates a similar safety and tolerability profile to other GLP-1 RAs. Semaglutide 2.4 mg treatment could dramatically improve clinical approaches to weight management, but the relatively high cost might prevent patients accessing treatment. Further research exploring the cost-effectiveness of subcutaneous semaglutide 2.4 mg is required.

The effect of nutrition and exercise training on irisin and semaphorin-3E levels in obese patients

We aimed to firstly examine the effects of nutrition and exercise training on irisin, Sema-3E, biochemical and inflammatory parameters in obese patients. This study was conducted using 37 individuals were divided into three groups according to body mass index (BMI) as non-obese, 1nd degree and 2nd degree obese individuals. Nutrition and exercise training were applied to groups for eight weeks. Insulin resistance decreased in non-obese and 1st degree obese subjects. HsCRP values decreased only in the second degree obese individuals. Adiponectin values were significantly decreased in all three groups. There was a negative correlation between serum adiponectin and plasma irisin levels both before and after treatment. Sema-3E levels increased significantly in only the first degree obese individuals, whereas plexin-D1 values did not change significantly in any group. Our findings indicate that nutrition and exercise training we apply improved both anthropometric measurements and biochemical parameters in obese and non-obese individuals.

Not All Type-2-Diabetes Patients Increase Body Mass Index After Initiating Insulin: Results of Latent Class Analysis from the DPV Registry

Background: Is insulin initiation linked to increasing body mass index (BMI) in all patients with type-2-diabetes (T2D)? To determine distinct longitudinal patterns of BMI change over time. Materials and Methods: 5057 patients with T2D (55% males, median BMI [IQR]: 30.0 [26.9-33.3] kg/m²) aged ≥40 years at diabetes diagnosis and with ≥2 years of follow-up after insulin initiation irrespective of previous or concurrent use of metformin/dipeptidyl peptidase-4-inhibitor from the multicenter prospective diabetes registry DPV were studied. To identify subgroups following a similar pattern of BMI change after insulin initiation, longitudinal group-based trajectory modeling was applied. Multinomial logistic regression was then used to analyze covariates associated with group membership. Results: Three heterogeneous groups with either relevant BMI increase (delta-BMI: +4.0 kg/m² after 2 years; 12% of patients); slight BMI increase (+0.4 kg/m²; 80%); or BMI decrease (-3.2 kg/m²; 8%) were identified. Patients with older age [OR (95% CI): 1.37 (1.11-1.69)] and obesity [2.05 (1.65-2.55)] before insulin start were more often in the BMI decreasing group, and less often in the BMI increasing class [0.80 (0.67-0.95); 0.82 (0.69-0.98)]. A worse HbA1c both at insulin start and during follow-up [1.90 (1.60-2.26); 1.17 (1.07-1.27)], a higher insulin dose [1.67 (1.33-2.10)], and severe hypoglycemic events [2.38 (1.60-3.53)] after insulin initiation were all linked with higher odds of belonging to the BMI increasing trajectory. Conclusions: Patient heterogeneity with respect to weight gain after initiation of insulin therapy in adult T2D was detected by an objective computer algorithm. Older people with obesity should not defer from insulin use due to fear of weight gain.

Daily Vigorous Intensity Physical Activity and Its Preventive Effect on Pancreatic Cancer

Purpose

There has been accumulating evidence for the preventive effect of high physical activity on cancer. However, it is still unclear which level of physical activity is associated with the decreased risk of pancreatic cancer. The purpose of current study is to assess the association between the frequency of vigorous intensity physical activity and the risk of pancreatic cancer.

Materials and Methods

The nationwide retrospective cohort study was conducted using the National Health Information Database. Study participants were 220,357 Koreans who received health check-up in 2009. They were divided into four groups by the weekly frequency of vigorous intensity physical activity longer than 20 minutes (group 1, no vigorous intensity physical activity (reference); group 2, 1–3 days; group 3, 4–5 days and group 4, 6–7 days). Cox proportional hazard model was used to calculate the adjusted hazard ratios (HRs) and 95% confidence interval (CI) for incident pancreatic cancer (adjusted HRs [95% CI]) according to the weekly frequency of vigorous intensity physical activity.

Results

For 4.38 years’ follow-up on average, 377 cases of pancreatic cancer developed. Subjects without incident pancreatic cancer had more favorable metabolic condition and higher physical activity than subjects with incident pancreatic cancer. Adjusted HRs and 95% CI indicated that only group 4 was significantly associated with the decreased risk of pancreatic cancer (group 1, reference; group 2, 1.10 [0.86–1.40]; group 3, 0.75 [0.45–1.25] and group 4, 0.47 [0.25–0.89]).

Conclusion

In this nationwide representative cohort study, near daily vigorous intensity physical activity showed the preventive effect on pancreatic cancer.

Longitudinal association of built environment pattern with DXA-derived body fat in elderly Hong Kong Chinese: a latent profile analysis

BACKGROUND

One major limitation of prior studies regarding the associations between built environment (BE) and obesity has been the use of anthropometric indices (e.g., body mass index [BMI]) for assessing obesity status, and there has been limited evidence of associations between BE and body fat. This study aimed to explore the longitudinal association between BE and body fat in a cohort of elderly Hong Kong Chinese and examine whether the BE-body fat associations differed by BMI categories.

METHODS

Between 2001 and 2003, 3944 participants aged 65-98 years were recruited and followed for a mean of 6.4 years. BE characteristics were assessed via Geographic Information System. Body fat (%) at whole body and regional areas (trunk, limbs, android, and gynoid) were assessed by dual energy X-ray absorptiometry at baseline and three follow-ups. Latent profile analysis was used to derive BE class, and linear mixed-effects models were used to investigate the associations of BE class with changes in body fat. Stratified analyses by BMI categories were also conducted.

RESULTS

Three BE classes were identified. Participants in Class 2 (characterized by greater open space and proportion of residential land use) had a slower increase in whole body fat (B = -0.403, 95% confidence interval [CI]: -0.780, -0.014) and limbs fat (-0.471, 95% CI: -0.870, -0.071) compared with participants in Class 1 (characterized by high proportion of commercial land use). There were significant interactions of BE class with BMI, and participants in Class 2 had a slower increase in whole body fat and regional fat compared with participants in Class 1 (B ranging from -0.987 [limbs] to -0.523 [gynoid]) among overweight and obese participants only.

CONCLUSIONS

We found that those who resided in the areas characterized by greater open space and proportion of residential land use had a slower body fat increase.

Evaluating the Potential Benefit of a Combined Weight Loss Program in Dogs and Their Owners

Introduction: Little has been published on the psychological bond between the owner and the pet, and how this might influence shared habits that could lead to overweight and obesity. Another factor that could improve the effectiveness of a weight loss plan, is that the owner would see the dog as a weight loss partner and therefore this could increase the motivation to follow the assigned diet and exercise guidelines.

Objective: The aim of this research was to evaluate the potential mutual effects of weight loss programs for both dogs and dog owners.

Methods: Two studies were conducted: In the human-centered trial, 60 dog owners were enrolled, who signed up to receive dietary and exercise recommendations to lose weight themselves during an 8 week period, from which 29 were randomly assigned to also get recommendations for their dog. For the dog-centered trial, we selected 13 dog owners that wanted their dog to lose weight during a 6 week period, from which 7 were randomly assigned to also get recommendations for themselves. The average weight loss over the time period was recorded. A questionnaire was used to evaluate diet and exercise habits, as well as information about the relationship between the dog and owner.

Results: The average human weight loss was 2.6% in the owner+dog group (n = 29) and 2.3% in the owner only group (n = 31; p > 0.05). Forty percent (24/60) of the dogs in the human-centered trial were overweight. The overweight dogs in the owner+dog group (n = 12/29) lost 3.7% of their body weight, compared to 1.2% in the overweight dogs from the owner only group (n = 12/31; p > 0.05). In the dog-centered trial, the 7 dogs in the dog+owner group lost 8.0% of their body weight, vs. 8.3% in the six dogs in the dog only group (p > 0.05). The owners in the dog+owner group lost 2.5% of their body weight, compared to 0.5% in the dog only group (p > 0.05). In both trials owners' perceived responsibility for both their own and their dogs' weight significantly increased. In addition, habit strength regarding unhealthy feeding and exercise behaviors in relation to the dogs decreased, and self-efficacy in relation to providing the dog with healthy food and exercise increased.

Conclusion: Active weight loss in either dog owner or dog, seemed to lead to passive weight loss in the other, especially when some tools or guidelines were provided. These findings support mutual benefits of weight loss programs for dogs and dog owners, and support future weight loss programs to be a One Health approach.

The information-motivation-behavioral skills model explains physical activity levels for adults with type 2 diabetes across all weight classes

Physical activity is an evidence-based, effective treatment for type 2 diabetes mellitus (T2D), yet insufficient numbers of adults achieve recommended daily levels, particularly amongst higher weight classes. This cross-sectional study assessed whether the Information-Motivation-Behavioural Skills (IMB) Model explained physical activity levels in adults with T2D across different body mass index (BMI) levels (N = 381). Measures included the American Adults Knowledge of Exercise Recommendations (AAKER), Behavioural Regulation in Exercise Questionnaire (BREQ-2), Barriers Specific Self-Efficacy Scale (BARSE) and the outcome measure, International Physical Activity Questionnaire (IPAQ-short form). Analyses included structural equation modelling (SEM) and ordinal logistic regression models. SEM demonstrated a good fit of the IMB Model to the data, accounting for 44% of variance in physical activity levels. Both motivation and self-efficacy had a direct effect, and motivation indirectly predicted physical activity through self-efficacy. Further analyses found the effect of the IMB predictors did not vary according to BMI status. This study supports the application of the IMB Model in explaining physical activity behavior in adults with T2D. In particular, the contribution of motivation and self-efficacy as substantive and modifiable predictors of physical activity will facilitate the development of targeted and evidence-based interventions for individuals of all BMI classes.

Additive stress of normobaric hypoxic conditioning to improve body mass loss and cardiometabolic markers in individuals with overweight or obesity: A systematic review and meta-analysis

We performed a systematic review and meta-analysis to determine if hypoxic conditioning, compared to similar training near sea level, maximizes body mass loss and further improves cardiometabolic markers in overweight and obese individuals. A systematic search of PubMed, Web of Science and the Cochrane Library databases (up to January 2019) was performed. This analysis included randomized controlled trials with humans with overweight or obesity assessing the effects of HC on body mass loss or cardiometabolic markers. A subgroup analysis was performed to examine if HC effects differed between individuals with overweight or obesity. 13 articles (336 participants) qualified for inclusion. HC significantly decreased body mass (p = .01), fat mass (p = .04), waist/hip ratio (p < .001), waist (p < .001), LDL (p = .01), diastolic (p < .01) and systolic blood pressure (p < .01) with these effects not being larger than equivalent normoxic interventions. There were trends towards higher triglycerides decrement (p = .06) and higher muscle mass gain in hypoxic (p = .08) compared with normoxic condition. Also, the two BMI categories displayed no difference in the magnitude of the responses. Compared to normoxic equivalent, HC provides greater reductions in triglycerides and greater muscle growth, while body mass changes are similar. In addition, HC responses were essentially similar between individuals with overweight or obesity.

Emotional intelligence, emotion regulation and affectivity in adults seeking treatment for obesity

Obesity has become an increasingly widespread endemic with social implications; however, the relationship between higher body mass index (BMI) and psychological functioning is still not fully understood. This study examined the differences in affect-related psychological variables among BMI classes. A total of 134 adults seeking treatment for obesity and 124 controls completed a set of questionnaires to assess: trait emotional intelligence, emotion regulation strategies, anxiety, depression, binge eating behaviors and happiness. Correlations and multivariate analysis of variance were run per each study variable controlling for BMI class (normal weight, overweight, or obesity class I, II, III). Individuals with obesity class III were characterized by reduced trait emotional intelligence and happiness, and a higher tendency to use emotion suppression compared to normal weight individuals. All individuals with obesity also showed higher levels of depression and binge eating behaviors compared to both normal weight and overweight adults. Depression and emotion suppression were the most relevant discriminant factors across BMI classes, while trait emotional intelligence resulted as an important psychological factor clustering individual differences between obese and non-obese individuals. These results suggest that more attention to the affective domain of psychological functioning is needed for proper and comprehensive treatment of obesity.

Determinants of successful lifestyle change during a 6-month preconception lifestyle intervention in women with obesity and infertility

PURPOSE

To identify demographic, (bio)physical, behavioral, and psychological determinants of successful lifestyle change and program completion by performing a secondary analysis of the intervention arm of a randomized-controlled trial, investigating a preconception lifestyle intervention.

METHODS

The 6-month lifestyle intervention consisted of dietary counseling, physical activity, and behavioral modification, and was aimed at 5-10% weight loss. We operationalized successful lifestyle change as successful weight loss (≥ 5% weight/BMI ≤ 29 kg/m²), weight loss in kilograms, a reduction in energy intake, and an increase in physical activity during the intervention program. We performed logistic and mixed-effect regression analyses to identify baseline factors that were associated with successful change or program completion.

RESULTS

Women with higher external eating behavior scores had higher odds of successful weight loss (OR 1.10, 95% CI 1.05-1.16). Women with the previous dietetic support lost 0.94 kg less during the intervention period (95% CI 0.01-1.87 kg). Women with higher self-efficacy reduced energy intake more than women with lower self-efficacy (p < 0.01). Women with an older partner had an increased energy intake (6 kcal/year older, 95% CI 3-13). A high stage of change towards physical activity was associated with a higher number of daily steps (p = 0.03). A high stage of change towards weight loss was associated with completion of the intervention (p = 0.04).

CONCLUSIONS

Determinants of lifestyle change and program completion were: higher external eating behavior, not having received previous dietetic support, high stage of change. This knowledge can be used to identify women likely to benefit from lifestyle interventions and develop new interventions for women requiring alternative support.

TRIAL REGISTRATION

The LIFEstyle study was registered at the Dutch trial registry (NTR 1530; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=1530 ).

Relative Influence of Socioeconomic, Psychological and Sensory Characteristics, Physical Activity and Diet on 5-Year Weight Gain in French Adults

Individual characteristics, dietary intake and physical activity influence weight status; however, the contribution of each factor to weight change has not been studied. The objective was to confirm a conceptual framework by simultaneously assessing the relative influence of socioeconomic, psychological and sensory characteristics, physical activity, and dietary intake on five-year weight gain in French adults. Individual characteristics, physical activity, and dietary data were assessed at baseline in 8014 participants in the NutriNet-Santé cohort. Self-reported anthropometric data were collected at baseline and five years later. Structural equation models, stratified by baseline body mass index (BMI), were used to perform analyses. Dietary restraint was a direct predictor of weight gain, with a stronger effect than age or intake of energy-dense foods, both in non-overweight and overweight participants. In non-overweight individuals only, intake of nutrient-dense foods and physical activity were inversely associated with weight gain. Regarding dietary intake, fat liking was the most important predictor of nutrient-dense food intake and was also related to energy-dense food intake. In these models, dietary restraint appears to be a direct predictor of weight gain and fat liking is a strong determinant of dietary intake. The influence of dietary restraint on weight gain, not explained by diet, warrants further investigation.

What factors influence weight loss in participants of commercial weight loss programmes? Implications for health policy

BACKGROUND

Finding effective referral policies for weight management services would have important public health implications.

AIM

Here we compare percentage weight change by referral methods, BMI categories and participants who have had attended weight loss programmes multiple times.

DESIGN AND SETTINGS

A prospective cohort study of 15,621 participants referred to 12-week behavioural weight loss programmes funded by the public health service in Birmingham, UK.

METHODS

Comparisons were made between GP versus self-referrals, BMI ≥40kg/m²-<40kg/m² and multiple referrals compared to only one referral. Linear mixed modelling was used to assess percentage weight change after adjusting for covariates.

RESULTS

Participant's mean age was 48.5 years, 78.7% were of white ethnicity, 90.3% female and mean baseline BMI was 36.3kg/m². There were no significant differences in percentage weight loss, between participants that self-referred and those that were referred by their general practitioner (GP) and no significant differences between baseline BMI categories. Referral to a weight loss programme more than once was associated with less weight loss at subsequent attendances (0.92%, 95% CI 0.70-1.14, p<0.001).

CONCLUSION

Allowing self-referral to a weight loss programme widens access without compromising amount of weight lost. These programmes are beneficial for all categories of obesity, including those with a BMI ≥40kg/m². Attending weight management programmes more than once results in less weight loss and that swapping to a different program may be advisable.

Impact of lifestyle intervention in primary prevention of Type 2 diabetes did not differ by baseline age and BMI among Asian-Indian people with impaired glucose tolerance

AIM

To investigate whether the effectiveness of lifestyle interventions on the incidence of diabetes was influenced by the baseline age and BMI of the Asian-Indian participants with prediabetes.

METHODS

Pooled data, obtained from two of our Indian Diabetes Prevention Programmes (2006, n=236 and 2013, n=473; total N=709) which had similar baseline characteristics and intervention principles, were analysed. For the present secondary analysis we dichotomously categorized the participants' baseline age (<45 and ≥45 years) and BMI (<25.0 and ≥ 25.0 kg/m² ). Glycaemic status was ascertained at 6-monthly intervals by oral glucose tolerance tests. The incidence rates of diabetes and relative risk reduction in both the intervention and the control group were calculated for categories of baseline age and BMI. Interactions between the intervention and baseline age and BMI on diabetes risk were also analysed.

RESULTS

Incident diabetes was diagnosed in 227 of the total 709 participants (32.0%) [control group 139 participants (38.8%) vs intervention group 88 participants (24.2%)] during the median follow-up period of 2 years. The overall relative risk reduction was 35.4% (95% CI 19.3-48.3). Lifestyle intervention was equally effective in both age groups [relative risk reduction in those aged <45 years: 43.7% (95% CI 19.8-60.5) and in those aged ≥ 45 years: 28.9% (95% CI 5.3-46.6) P for interaction = 0.52] and in categories of BMI [BMI <25 kg/m² : 36.1% (95% CI 9.5-54.9); and BMI ≥ 25 kg/m² : 34.8% (95% CI 12.9-51.2); P for interaction = 0.95].

CONCLUSIONS

In Asian-Indian individuals with prediabetes, the effectiveness of lifestyle intervention was not modified by baseline age and BMI.

Longitudinal associations of active commuting with body mass index

OBJECTIVE

To investigate the longitudinal associations between active commuting (walking and cycling to work) and body mass index (BMI).

METHOD

We used self-reported data on height, weight and active commuting from the Commuting and Health in Cambridge study (2009 to 2012; n=809). We used linear regression to test the associations between: a) maintenance of active commuting over one year and BMI at the end of that year; and b) change in weekly time spent in active commuting and change in BMI over one year.

RESULTS

After adjusting for sociodemographic variables, other physical activity, physical wellbeing and maintenance of walking, those who maintained cycle commuting reported a lower BMI on average at one year follow-up (1.14kg/m(2), 95% CI: 0.30 to 1.98, n=579) than those who never cycled to work. No significant association remained after adjustment for baseline BMI. No significant associations were observed for maintenance of walking. An increase in walking was associated with a reduction in BMI (0.32kg/m(2), 95% CI: 0.03 to 0.62, n=651, after adjustment for co-variates and baseline BMI) only when restricting the analysis to those who did not move. No other significant associations between changes in weekly time spent walking or cycling on the commute and changes in BMI were observed.

CONCLUSIONS

This work provides further evidence of the contribution of active commuting, particularly cycling, to preventing weight gain or facilitating weight loss. The findings may be valuable for employees choosing how to commute and engaging employers in the promotion of active travel.

Effects of a Family-Based Childhood Obesity Treatment Program on Parental Weight Status

Objective

The aim of this study was to investigate the prevalence of overweight/obesity among parents of children entering childhood obesity treatment and to evaluate changes in the parents’ weight statuses during their child’s treatment.

Methods

The study included parents of 1,125 children and adolescents aged 3–22 years, who were enrolled in a multidisciplinary childhood obesity treatment program. At baseline, weight and height of the parents were obtained by self-reported information and parental body mass index (BMI) was calculated. Weight and height of the children were measured in the clinic and BMI standard deviation scores were calculated. Furthermore, anthropometric data from parents of 664 children were obtained by telephone interview after a mean of 2.5 years of treatment (ranging 16 days to 7 years), and changes in parental BMI were analyzed.

Results

Data on changes in BMI were available in 606 mothers and 479 fathers. At baseline, the median BMI of the mothers was 28.1 kg/m² (range: 16.9–66.6), and the median BMI of the fathers was 28.9 kg/m² (range: 17.2–48.1). Seventy percent of the mothers and 80% of the fathers were overweight or obese at the time of their child’s treatment initiation. Both the mothers and fathers lost weight during their child’s treatment with a mean decrease in BMI in the mothers of 0.5 (95% CI: 0.2–0.8, p = 0.0006) and in the fathers of 0.4 (95% CI: 0.2–0.6, p = 0.0007). Of the overweight/obese parents, 60% of the mothers and 58% of the fathers lost weight during their child’s treatment.

Conclusion

There is a high prevalence of overweight/obesity among parents of children entering childhood obesity treatment. Family-based childhood obesity treatment with a focus on the child has a positive effect on parental BMI with both mothers and fathers losing weight.

Trial Registration

ClinicalTrials.gov NCT00928473

Gender Differences in Weight-Related Attitudes and Behaviors Among Overweight and Obese Adults in the United States

Few studies have used nationally representative data to focus specifically on gender differences in weight-related outcomes. This article examines gender differences in weight-related outcomes across the body mass index (BMI) spectrum in overweight and obese adults. Data from the National Health and Nutrition Examination Survey 2009–2010 was analyzed. Weight-related outcomes were accurate weight perception, weight dissatisfaction, attempted weight loss, successful weight loss, and weight loss strategies. Compared with women, overweight and obese men were less likely to have accurate weight perception (odds ratio [OR] = 0.36; 95% confidence interval [CI] = 0.30–0.44), weight dissatisfaction (OR = 0.39; 95% CI = 0.32–0.47), and attempted weight loss (OR = 0.55; 95% CI = 0.48–0.63). The modifying effect of gender on these associations decreased as BMI increased. By BMI 35, the mean probability of women and men to have accurate weight perception and weight dissatisfaction was 90%; attempted weight loss was 60% (women) and 50% (men). At lower BMIs, men had up to 40% less probability than women for these weight loss outcomes. Men who attempted weight loss were more likely than women to lose and maintain ≥10 lb over 1 year (OR = 1.41; 95% CI = 1.20–1.65) and increase exercise and eat less fat as weight loss strategies; women were more likely to join weight loss programs, take prescription diet pills, and follow special diets. A need exists for male-specific interventions to improve overweight and obese men’s likelihood for accurate weight perception, attempted weight loss, and ultimately, successful weight loss.

The Effects of a "Health at Every Size(®)"-Based Approach in Obese Women: A Pilot-Trial of the "Health and Wellness in Obesity" Study

This study explored the effects of Health at Every Size(®)-based intervention on obese women by qualitatively evaluating participants' perception toward the program and quantitatively evaluating changes related to psychological, behavioral, and body composition assessments. A prospective 1-year quasi-experimental mixed-method trial was conducted. The mixed-method design was characterized by a spiral method, and quantitative and qualitative findings were combined during the interpretation phase. The qualitative data involved three focus groups; and quantitative data comprised physiological, psychological, and behavioral assessments. Initially, 30 participants were recruited; 14 concluded the intervention. From the focus groups, the following interpretative axes were constructed: the intervention as a period of discoveries; shifting parameters: psychological, physical, and behavioral changes; eating changes, and; redefining success. Body weight, body mass index, total body fat mass, and body fat percentage were significantly decreased after the intervention (-3.6, -3.2, -13.0, and -11.1%, respectively; p ≤ 0.05, within-time effect). Participants reported to be more physically active and perceiving better their bodies. Eating-wise, participants reported that the hunger and satiety cues and the consumption of more frequent meals facilitated their eating changes. Finally, participants reported that they could identify feelings with eating choices and refrain from the restrained behavior. These qualitative improvements were accompanied by modest but significant improvements in quantitative assessments. Clinicaltrials.gov registration: NCT02102061.

Primary care weight loss maintenance with behavioral nutrition: An observational study

OBJECTIVE

To evaluate the rate of weight loss maintenance, defined as a 10% loss of initial weight maintained beyond 1 year, among patients with BMI > 25 kg/m(2) who had been managed by primary care physicians practicing behavioral nutrition (moderately high-protein diet, carbohydrate restriction, and behavioral therapy).

METHODS

Restrospective analysis of anthropometric characteristics, weight loss, and its determinants was conducted in 14,256 patients.

RESULTS

26.7% of subjects met the success criterion (successful maintenance group; SM), 25.7% did not maintain their weight loss (unsuccessful maintenance group; UM), and 47.6% did not lose 10% of their initial weight (failure group; F). At inclusion, patients in the SM group had a greater BMI and fat mass percentage (40.5% in SM, 38.5% in UM, and 37.0% in F). These patients lost more weight (-14.1% vs. -4.59%) and fat mass (-24.7% vs. -8.21%) than patients in the UM group, and contribution of adiposity to their weight loss was 75.1%. Follow-up of patients in the SM group was characterized by a greater frequency of consultations.

CONCLUSIONS

Management by primary care providers with behavioral nutrition facilitates weight loss maintenance in patients with overweight and obesity. The determinants of success are frequency of consultations, initial BMI, and initial weight loss.

Impact of the obesity epidemic on cancer

There is growing appreciation that the current obesity epidemic is associated with increases in cancer incidence at a population level and may lead to poor cancer outcomes; concurrent decreases in cancer mortality at a population level may represent a paradox, i.e., they may also reflect improvements in the diagnosis and treatment of cancer that mask obesity effects. An association of obesity with cancer is biologically plausible because adipose tissue is biologically active, secreting estrogens, adipokines, and cytokines. In obesity, adipose tissue reprogramming may lead to insulin resistance, with or without diabetes, and it may contribute to cancer growth and progression locally or through systemic effects. Obesity-associated changes impact cancer in a complex fashion, potentially acting directly on cells through pathways, such as the phosphoinositide 3-kinase (PI3K) and Janus kinase-signal transducer and activator of transcription (JAK-STAT) pathways, or indirectly via changes in the tumor microenvironment. Approaches to obesity management are discussed, and the potential for pharmacologic interventions that target the obesity-cancer link is addressed.