Efficacy Of Weight Loss Intervention Research Articles

Intermittent fasting, exercise, and dietary modification induce unique transcriptomic signatures of multiple tissues governing metabolic homeostasis during weight loss and rebound weight gain

Obesity and its related metabolic diseases bring great challenges to public health. In-depth understanding on the efficacy of weight-loss interventions is critical for long-term weight control. Our study demonstrated the comparable efficacy of exercise (EX), intermittent fasting (IF), or the change of daily diet from an unhealthy to a normal chow (DR) for weight reduction, but largely divergently affected metabolic status and transcriptome of subcutaneous fat, scapular brown fat, skeletal muscles and liver in high-fat-high-fructose diet (HFHF) induced obese mice. EX and IF reduced systematic inflammation, improved glucose and lipid metabolism in liver and muscle, and amino acid metabolism and thermogenesis in adipose tissues. EX exhibited broad regulatory effects on TCA cycle, carbon metabolism, thermogenesis, propanoate-, fatty acid and amino acid metabolism across multiple tissues. IF prominently affected genes involved in mitophagy and autophagy in adipose tissues and core genes involved in butanoate metabolism in liver. DR, however, failed to improve metabolic homeostasis and biological dysfunctions in obese mice. Notably, by exploring potential inter-organ communication, we identified an obesity-resistant-like gene profile that were strongly correlated with HFHF induced metabolic derangements and could predict the degree of weight regain induced by the follow-up HFHF diet. Among them, 12 genes (e.g., Gdf15, Tfrc, Cdv3, Map2k4, and Nqo1) were causally associated with human metabolic traits, i.e., BMI, body fat mass, HbA1C, fasting glucose, and cholesterol. Our findings provide critical groundwork for improved understanding of the impacts of weight-loss interventions on host metabolism. The identified genes predicting weight regain may be considered regulatory targets for improving long-term weight control.

Late Luteal Subphase Food Craving Is Enhanced in Women with Obesity and Premenstrual Dysphoric Disorder (PMDD)

Dysregulated food craving is a complex weight-related behavior. To identify novel targets for enhancing the efficacy of weight loss interventions, we examined whether food craving varies across the menstrual cycle according to the abdominal obesity type and premenstrual dysphoric disorder (PMDD) diagnosis, and, if so, whether it is related to affective symptomatology. Reproductive-age women were classified into one of the four study groups according to whether they have abdominal obesity (AO) or are abdominally lean (AL), and the presence of PMDD: (1) AO:PMDD+ (n = 13), (2) AL:PMDD+ (n = 14), (3) AO:PMDD− (n = 15), and (4) AL:PMDD− (n = 16). Self-report measures as well as urinary luteinizing hormone (LH) tests were provided by the participants across 2–3 menstrual cycles. The ratings of food cravings were similar across the menstrual cycle, except the last, late luteal subphase as the AO:PMDD+ participants had the highest food craving rating. Irritability and depression were correlated with food cravings, but not in a distinctive manner across the menstrual cycle by group. Our study found that women with abdominal obesity and PMDD display a temporal vulnerability to a food-related behavior. The possibility of shared neurobiology between the two conditions is discussed and should be examined in future studies.

Weight Management Post-Stroke: A Scoping Review

Purpose: The aim of this scoping review is to comprehensively review the available literature on the influence of intentional weight loss on physical function and psychosocial outcomes during rehabilitation of chronic stroke survivors. Materials and Methods: Experimental and observational studies evaluating weight loss, physical function, and psychosocial outcomes in chronic stroke survivors were searched in PubMed, EMBASE, and CINAHL databases using the following search terms: obesity, BMI, body composition, stroke. The search yielded 376 articles. After review of titles, abstracts, and full texts, 4 studies were included in the review. Results: All studies reported significant weight loss and/or improvement in body composition among chronic stroke survivors. In addition, all studies reported significant improvements in at least one measure of physical function, psychosocial outcomes, or both. While these studies met inclusion criteria and, thus, were included in this review, it is noteworthy that methodologies and aims varied significantly. While this review suggests physical function and psychosocial benefits of weight loss in chronic stroke survivors, further attention to this issue by research and funding agencies is imperative to determine the efficacy of weight loss interventions for physical function and psychosocial outcomes among the large population of chronic stroke survivors with obesity.

Spatiotemporal profile of altered neural reactivity to food images in obesity: Reward system is altered automatically and predicts efficacy of weight loss intervention.

Obesity presents a significant public health problem. Brain plays a central role in etiology and maintenance of obesity. Prior neuroimaging studies have found that individuals with obesity exhibit altered neural responses to images of food within the brain reward system and related brain networks. However, little is known about the dynamics of these neural responses or their relationship to later weight change. In particular, it is unknown if in obesity, the altered reward response to food images emerges early and automatically, or later, in the controlled stage of processing. It also remains unclear if the pretreatment reward system reactivity to food images is predictive of subsequent weight loss intervention outcome. In this study, we presented high-calorie and low-calorie food, and nonfood images to individuals with obesity, who were then prescribed lifestyle changes, and matched normal-weight controls, and examined neural reactivity using magnetoencephalography (MEG). We performed whole-brain analysis to explore and characterize large-scale dynamics of brain systems affected in obesity, and tested two specific hypotheses: (1) in obese individuals, the altered reward system reactivity to food images occurs early and automatically, and (2) pretreatment reward system reactivity predicts the outcome of lifestyle weight loss intervention, with reduced activity associated with successful weight loss. We identified a distributed set of brain regions and their precise temporal dynamics that showed altered response patterns in obesity. Specifically, we found reduced neural reactivity to food images in brain networks of reward and cognitive control, and elevated reactivity in regions of attentional control and visual processing. The hypoactivity in reward system emerged early, in the automatic stage of processing (< 150 ms post-stimulus). Reduced reward and attention responsivity, and elevated neural cognitive control were predictive of weight loss after six months in treatment. In summary, we have identified, for the first time with high temporal resolution, the large-scale dynamics of brain reactivity to food images in obese versus normal-weight individuals, and have confirmed both our hypotheses. These findings have important implications for our understanding of neurocognition and eating behavior in obesity, and can facilitate development of novel integrated treatment strategies, including tailored cognitive-behavioral and pharmacological therapies.

The evidential value of research on cognitive training to change food-related biases and unhealthy eating behavior: A systematic review and p-curve analysis.

Cognitive bias modification (CBM), which retrains implicit biases towards unhealthy foods, has been proposed as a promising adjunct to improve the efficacy of weight loss interventions. We conducted a systematic review of research on three CBM approaches (i.e., cue-specific inhibitory control, approach bias modification, and attentional bias modification) for reducing unhealthy eating biases and behavior. We performed a p-curve analysis to determine the evidential value of this research; this method is optimally suited to clarify whether published results reflect true effects or false positives due to publication and reporting biases. When considering all CBM approaches, our results suggested that the findings of CBM trials targeting unhealthy eating are unlikely to be false positives. However, only research on attentional bias modification reached acceptable levels of power. These results suggest that CBM interventions may be an effective strategy to enhance the efficacy of weight loss interventions. However, there is room for improvement in the methodological standards of this area of research, especially increasing the statistical power can help to fully clarify the clinical potential of CBM, and determine the role of potential moderators.

Efficacy of Weight Loss Interventions in United States Active Duty Military Populations: A Systematic Review.

Since the beginning of overseas contingency operations, the percent of service members who are considered overweight or obese has tripled to 15% for men and 20% for women. This has implications for national security if the country is unable to staff its military with fit-to-fight individuals. The purpose of this systematic review is to move policy efforts forward by illuminating the efficacy of several lifestyle interventions for active duty service members since 2001. It aims to both identify common aspects of successful interventions and also identify interventions without success so DoD leaders may replace those initiatives. The electronic database PubMed was searched from September 11, 2001 to May 15, 2020. Studies were included if the target population was United States active duty service members from any branch, the study included an intervention, and the measured outcome was weight loss. Seven studies met final inclusion criteria. Interventions with corresponding weight loss data are summarized in Table III. This review found that there is not a sufficient body of evidence to determine if interventions to aid active duty service members in losing weight are effective. However, as a collection, the studies could support the notion that military members get the best results when interventions are convenient, modern, personalized, and accessible. More studies are needed, and future studies with larger sample sizes and longer durations would be valuable in determining efficacy of weight loss interventions. Undoubtedly, enrollment and compliance is difficult with military member moves and competing mission requirements. Ideally, the DoD should work to aggregate the efforts in this field, as many initiatives are not captured, shared, and utilized by other installations or other services. Data silos and unpublished or underdeveloped research reactively addresses issues and does not proactively address them. Policy change will need to be nested in further research, as well as consider the food environment on bases and possible prevention efforts.

Cardiometabolic efficacy of multidisciplinary weight loss interventions is not altered in adolescents with obesity initially diagnosed or with a persistent metabolic syndrome

The efficacy of weight loss interventions might be affected by the metabolic profile of adolescents with obesity. In this study, we hypothesized that the initial diagnosis of the MS, or its persistence after an intervention, will not reduce the efficacy of a 16-week multidisciplinary weight loss program. Ninety two adolescents (12-15 years; 62 girls) with obesity completed baseline anthropometric and body composition evaluation (DXA). Lipid profile, insulinemia, glycaemia and blood pressure were measured and metabolic syndrome (MS) diagnosed. The adolescents then followed a 4-month inpatient multidisciplinary weight-management program. All measurements were performed before (T0) and after 4 months of intervention (T1). Body weight, body mass index (BMI) and percentage of fat mass (%FM) decreased significantly between T0 and T1 (P< .001), with no difference in fat-free mass (kg). All metabolic variables (except blood pressure) were improved. 47.6% of the whole sample presented with MS at baseline against 35.7% at T1. Body weight (P = 0.006), BMI (P = 0.0261), %FM (P = 0.0211), hip circumference (= 0.0131), BMI percentile (P = 0.0319), and diastolic blood pressure (P = 0.0365) showed a time x group interaction and their deltas (variations between T0 and T1) were significantly different between adolescents with and without MS at baseline. There was no significant difference between adolescents with persistent and nonpersistent MS except for ΔBMI percentile that deceased significantly more in the nonpersistent group (P = 0.0115). According to our results, the efficacy of weight loss interventions is not reduced in adolescents initially diagnosed with MS or different between those who present a persistent or nonpersistent MS after the intervention.

Text messaging and brief phone calls for weight loss in overweight and obese English- and Spanish-speaking adults: A 1-year, parallel-group, randomized controlled trial.

BackgroundWeight loss interventions based solely on text messaging (short message service [SMS]) have been shown to be modestly effective for short periods of time and in some populations, but limited evidence is available for positive longer-term outcomes and for efficacy in Hispanic populations. Also, little is known about the comparative efficacy of weight loss interventions that use SMS coupled with brief, technology-mediated contact with health coaches, an important issue when considering the scalability and cost of interventions. We examined the efficacy of a 1-year intervention designed to reduce weight among overweight and obese English- and Spanish-speaking adults via SMS alone (ConTxt) or in combination with brief, monthly health-coaching calls. ConTxt offered 2–4 SMS/day that were personalized, tailored, and interactive. Content was theory- and evidence-based and focused on reducing energy intake and increasing energy expenditure. Monthly health-coaching calls (5–10 minutes’ duration) focused on goal-setting, identifying barriers to achieving goals, and self-monitoring.Methods and findingsEnglish- and Spanish-speaking adults were recruited from October 2011 to March 2013. A total of 298 overweight (body mass index [BMI] 27.0 to 39.9 kg/m2) adults (aged 21–60 years; 77% female; 41% Hispanic; 21% primarily Spanish speaking; 44% college graduates or higher; 22% unemployed) were randomly assigned (1:1) to receive either ConTxt only (n = 101), ConTxt plus health-coaching calls (n = 96), or standard print materials on weight reduction (control group, n = 101). We used computer-based permuted-block randomization with block sizes of three or six, stratified by sex and Spanish-speaking status. Participants, study staff, and investigators were masked until the intervention was assigned. The primary outcome was objectively measured percent of weight loss from baseline at 12 months. Differences between groups were evaluated using linear mixed-effects regression within an intention-to-treat framework. A total of 261 (87.2%) and 253 (84.9%) participants completed 6- and 12-month visits, respectively. Loss to follow-up did not differ by study group. Mean (95% confidence intervals [CIs]) percent weight loss at 12 months was −0.61 (−1.99 to 0.77) in the control group, −1.68 (−3.08 to −0.27) in ConTxt only, and −3.63 (−5.05 to −2.81) in ConTxt plus health-coaching calls. At 12 months, mean (95% CI) percent weight loss, adjusted for baseline BMI, was significantly different between ConTxt plus health-coaching calls and the control group (−3.0 [−4.99 to −1.04], p = 0.003) but not between the ConTxt-only and the control group (−1.07 [−3.05 to 0.92], p = 0.291). Differences between ConTxt plus health-coaching calls and ConTxt only were not significant (−1.95 [−3.96 to 0.06], p = 0.057). These findings were consistent across other weight-related secondary outcomes, including changes in absolute weight, BMI, and percent body fat at 12 months. Exploratory subgroup analyses suggested that Spanish speakers responded more favorably to ConTxt plus health-coaching calls than English speakers (Spanish contrast: −7.90 [−11.94 to −3.86], p < 0.001; English contrast: −1.82 [−4.03 to 0.39], p = 0.107). Limitations include the unblinded delivery of the intervention and recruitment of a predominantly female sample from a single site.ConclusionsA 1-year intervention that delivered theory- and evidence-based weight loss content via daily personalized, tailored, and interactive SMS was most effective when combined with brief, monthly phone calls.Trial registrationClinicalTrials.gov NCT01171586

Efficacy of weight loss intervention can be predicted based on early alterations of fMRI food cue reactivity in the striatum

Increased fMRI food cue reactivity in obesity, i.e. higher responses to high- vs. low-calorie food images, is a promising marker of the dysregulated brain reward system underlying enhanced susceptibility to obesogenic environmental cues. Recently, it has also been shown that weight loss interventions might affect fMRI food cue reactivity and that there is a close association between the alteration of cue reactivity and the outcome of the intervention. Here we tested whether fMRI food cue reactivity could be used as a marker of diet-induced early changes of neural processing in the striatum that are predictive of the outcome of the weight loss intervention. To this end we investigated the relationship between food cue reactivity in the striatum measured one month after the onset of the weight loss program and weight changes obtained at the end of the six-month intervention. We observed a significant correlation between BMI change measured after six months and early alterations of fMRI food cue reactivity in the striatum, including the bilateral putamen, right pallidum, and left caudate. Our findings provide evidence for diet-induced early alterations of fMRI food cue reactivity in the striatum that can predict the outcome of the weight loss intervention.

Discordance Between Body Mass Index (BMI) and a Novel Body Composition Change Index (BCCI) as Outcome Measures in Weight Change Interventions

ABSTRACTObjective: A general assumption is that the body mass index (BMI) reflects changes in fat mass (FM). However, it fails to distinguish the type of weight that is lost or gained—fat mass (FM) or fat-free mass (FFM). The BMI treats both changes the same although they have opposite health consequences. The objective of this study was to propose a more precise measure, a body composition change index (BCCI), which distinguishes between changes in FM and FFM, and this study compares it with using the BMI as an outcome measure.Methods: Data were obtained from 3,870 subjects who had completed dual-energy x-ray absorptiometry (DEXA) total body scans at baseline and end-of-study when participating in a variety of weight-loss interventions. Since height remained constant in this adult cohort, changes in the BMI corresponded with scale weight changes (r = 0.994), allowing BMI changes to be converted to “lbs.” to match the statistic used for calculation of the BCCI. The BCCI is calculated by scoring increases in FFM (lbs.) and decreases in FM (lbs.) as positive outcomes and scoring decreases in FFM and increases in FM as negative outcomes. The BCCI is the net sum of these calculations. Differences between scale weight changes and BCCI values were subsequently compared to obtain “discordance scores.”Results: Discordance scores ranged from 0.0 lbs. to >30.0 lbs. with a mean absolute value of between the two measures of 7.79 lbs. (99% confidence interval: 7.49-8.10, p <0.00001), SD = 7.4 lbs. Similar discordance scores were also found in subgroups of self-reported gender, ethnicity, and age.Conclusions: A significant difference of 7.79 lbs. was found between the BCCI and the BMI to evaluate the efficacy of weight loss interventions. If assessing changes in body composition is a treatment goal, use of the BMI could result in significantly erroneous conclusions.

Does stress influence sleep patterns, food intake, weight gain, abdominal obesity and weight loss interventions and vice versa?

Decades of research have reported only weak associations between the intakes of specific foods or drinks and weight gain and obesity. Randomized controlled dietary intervention trials have only shown very modest effects of changes in nutrient intake and diet composition on body weight in obese subjects. This review summarizes the scientific evidence on the role mental stress (either in or not in association with impaired sleep) may play in poor sleep, enhanced appetite, cravings and decreased motivation for physical activity. All these factors contribute to weight gain and obesity, possibly via decreasing the efficacy of weight loss interventions. We also review evidence for the role that lifestyle and stress management may play in achieving weight loss in stress-vulnerable individuals with overweight.

Web-Based Interventions for Weight Loss or Weight Loss Maintenance in Overweight and Obese People: A Systematic Review of Systematic Reviews

BackgroundWeight loss is challenging and maintenance of weight loss is problematic. Web-based programs offer good potential for delivery of interventions for weight loss or weight loss maintenance. However, the precise impact of Web-based weight management programs is still unclear.ObjectiveThe purpose of this meta-systematic review was to provide a comprehensive summary of the efficacy of Web-based interventions for weight loss and weight loss maintenance.MethodsElectronic databases were searched for systematic reviews and meta-analyses that included at least one study investigating the effect of a Web-based intervention on weight loss and/or weight loss maintenance among samples of overweight and/or obese individuals. Twenty identified reviews met the inclusion criteria. The Revised Assessment of Multiple SysTemAtic Reviews (R-AMSTAR) was used to assess methodological quality of reviews. All included reviews were of sufficient methodological quality (R-AMSTAR score ≥22). Key methodological and outcome data were extracted from each review.ResultsWeb-based interventions for both weight loss and weight loss maintenance were more effective than minimal or control conditions. However, when contrasted with comparable non-Web-based interventions, results were less consistent across reviews.ConclusionsOverall, the efficacy of weight loss maintenance interventions was stronger than the efficacy of weight loss interventions, but further evidence is needed to more clearly understand the efficacy of both types of Web-based interventions.Trial RegistrationPROSPERO 2015: CRD42015029377; http://www.crd.york.ac.uk/PROSPERO/display_record.asp? ID=CRD42015029377 (Archived by WebCite at http://www.webcitation.org/6qkSafdCZ)

Effect of weight reduction on glycated haemoglobin in weight loss trials in patients with type 2 diabetes.

To quantify the effect of weight loss on glycated haemoglobin (HbA1c) at group level, based on data from published weight loss trials in overweight and obese patients with type 2 diabetes (T2D). A systematic literature search in MEDLINE, EMBASE and Cochrane CENTRAL (January 1990 through December 2012) was conducted to identify prospective trials of energy-reduced diets, obesity drugs or bariatric surgery in adult, overweight and obese patients with T2D. Based on clinical data with follow-up from 3 to 24 months, a linear model was developed to describe the effect of weight reduction on HbA1c. The literature search identified 58 eligible articles consisting of 124 treatment groups and 17 204 subjects, yielding a total of 250 data points with concurrent mean changes from baseline in weight and HbA1c. The model-based analyses indicated a linear relationship between weight loss and HbA1c reduction, with an estimated mean HbA1c reduction of 0.1 percentage points for each 1 kg of reduced body weight for the overall population. Baseline HbA1c was a significant covariate for the relationship between weight loss and HbA1c: high HbA1c at baseline was associated with a greater reduction in HbA1c for the same degree of weight loss. The collected trial data also indicated weight-loss-dependent reductions in antidiabetic medication. At group level, weight loss in obese and overweight patients with T2D was consistently accompanied by HbA1c reduction in a dose-dependent manner. The model developed in the present study estimates that for each kg of mean weight loss, there is a mean HbA1c reduction of 0.1 percentage points. HbA1c-lowering is greater in populations with poor glycaemic control than in well controlled populations with the same degree of weight loss. This summary of data from previous trials regarding the effect of weight reduction on HbA1c may be used to support the design and interpretation of future studies that aim to demonstrate the efficacy of weight loss interventions for T2D treatment.

A meta-analysis of overall effects of weight loss interventions delivered via mobile phones and effect size differences according to delivery mode, personal contact, and intervention intensity and duration.

Weight loss interventions are delivered through various mediums including, increasingly, mobile phones. This systematic review and meta-analysis assesses whether interventions delivered via mobile phones reduce body weight and which intervention characteristics are associated with efficacy. The study included randomised controlled trials assessing the efficacy of weight loss interventions delivered via mobile phones. A meta-analysis to test intervention efficacy was performed, and subgroup analyses were conducted to determine whether interventions' delivery mode(s), inclusion of personal contact, duration and interaction frequency improve efficacy. Pooled body weight reduction (d=-0.23; 95% confidence interval=-0.38, -0.08) was significant. Interventions delivered via other modes in addition to the mobile phone were associated with weight reduction. Personal contact and more frequent interactions in interventions were also associated with greater weight reduction. In conclusion, the current body of evidence shows that interventions delivered via mobile phones produce a modest reduction in body weight when combined with other delivery modes. Delivering interventions with frequent and personal interactions may in particular benefit weight loss results.

Obesity and cardiovascular disease

The prevalence of obesity has reached epidemic proportions, and in terms of the extent of its negative impact on the health has been compared to those of tobacco and alcohol. One of the first medical consequences of obesity to be recognised was cardiovascular disease (CVD). Obesity, particularly abdominal obesity, predisposes a person to a number of other cardiovascular risk factors, and is an independent predictor of clinical CVD including coronary death, coronary heart disease, heart failure and stroke. A Medline search using the following keywords (obesity, cardiovascular disease, body mass index, cardiovascular risk factors, type 2 diabetes, metabolic syndrome) was performed looking for high impact factor English-written references. Ninety-nine (N=99) relevant articles published in the last 15 years were selected and commented. As detailed throughout the text, current therapies available for weight management can improve or prevent many of these obesity-related risk factors for CVD. However, there is some controversy as to whether weight loss is beneficial for health, and large clinical outcome trials such as the Look-AHEAD (Action for Health in Diabetes) trial or the SCOUT (Sibutramine Cardiovascular Outcomes Trial) study are currently ongoing. In the present review, we summarise the effects of obesity as well as the efficacy of weight-loss interventions on cardiovascular risk factors and CVD.

What is the quality of reporting in weight loss intervention studies? A systematic review of randomized controlled trials

Despite the large number of randomized controlled trials (RCTs) assessing weight loss interventions, no study has assessed the quality of reporting in these trials. To assess the quality of reporting of RCTs of weight loss interventions and to identify predictors of reporting quality. The RCTs assessed were derived from a published systematic review of trials investigating the efficacy of weight loss interventions. For our study, two reviewers independently rated the quality of reporting in these trials, based on the Consolidated Standards for Reporting of Trials (CONSORT) Statement. We describe the quality of reporting using number (percent) of studies satisfying each of the 44 CONSORT criteria. We use generalized estimating equations (GEE) to fit a multivariable regression model to determine factors that are associated with the overall quality reporting score. We assessed 63 RCTs, of which 25 were dietary-lifestyle trials, 22 were pharmacological trials and 16 were behavior-cognitive, exercise-lifestyle, or surgical trials. Less than half (46%) of the trials defined the primary outcome of the study; about 10% provided the description of the method of allocation concealment. Multivariable GEE results showed that the sample size, type of intervention (non-pharmacologic trials having lower scores than pharmacologic trials), and publication time relative to the CONSORT Statement publication in 1996 (publications after 1996 having higher scores) were strong predictors of the quality reporting score. Reporting a statistically significant result on the primary outcome was not significantly associated with the quality score. While the overall quality in reporting seemed to have improved since the publication of the revised CONSORT Statement in 1996, the reporting of some key methodologic aspects, such as clear description of primary outcome and method of allocation concealment, still requires improvements. Factors that are significantly associated with the overall quality reporting score can be used as surrogates in the review of protocols to enhance the quality of the final reports.