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Frontiers in Endocrinology 2021Obesity is a complex multifactorial disease that accumulated excess body fat leads to negative effects on health. Obesity continues to accelerate resulting in an... (Review)
Review
Obesity is a complex multifactorial disease that accumulated excess body fat leads to negative effects on health. Obesity continues to accelerate resulting in an unprecedented epidemic that shows no significant signs of slowing down any time soon. Raised body mass index (BMI) is a risk factor for noncommunicable diseases such as diabetes, cardiovascular diseases, and musculoskeletal disorders, resulting in dramatic decrease of life quality and expectancy. The main cause of obesity is long-term energy imbalance between consumed calories and expended calories. Here, we explore the biological mechanisms of obesity with the aim of providing actionable treatment strategies to achieve a healthy body weight from nature to nurture. This review summarizes the global trends in obesity with a special focus on the pathogenesis of obesity from genetic factors to epigenetic factors, from social environmental factors to microenvironment factors. Against this background, we discuss several possible intervention strategies to minimize BMI.
Topics: Adipose Tissue; Animals; Body Mass Index; Body Weight; Energy Intake; Humans; Obesity; Risk Factors
PubMed: 34552557
DOI: 10.3389/fendo.2021.706978 -
International Journal of Environmental... Aug 2022A ketogenic diet, characterized by low calories with high levels of fat, adequate levels of protein, and low levels of carbohydrates, has beneficial effects on body... (Meta-Analysis)
Meta-Analysis Review
Ketogenic Diet Benefits to Weight Loss, Glycemic Control, and Lipid Profiles in Overweight Patients with Type 2 Diabetes Mellitus: A Meta-Analysis of Randomized Controlled Trails.
A ketogenic diet, characterized by low calories with high levels of fat, adequate levels of protein, and low levels of carbohydrates, has beneficial effects on body weight control in overweight patients. In the present study, a meta-analysis was conducted to investigate the role of a ketogenic diet in body weight control and glycemic management in overweight patients with type 2 diabetes mellitus (T2DM). In summary, we systematically reviewed articles from the Embase, PubMed, Web of Science and Cochrane Library databases and obtained eight randomized controlled trials for meta-analysis. The results show that a ketogenic diet had significantly beneficial effects on the loss of body weight (SMD, -5.63, = 0.008), the reduction of waist circumference (SMD, -2.32, = 0.04), lowering glycated hemoglobin (SMD, -0.38, = 0.0008) and triglycerides (SMD, -0.36, = 0.0001), and increasing high-density lipoproteins (SMD, 0.28, = 0.003). Overall, these results suggest that a ketogenic diet may be an effective dietary intervention for body weight and glycemic control, as well as improved lipid profiles in overweight patients with T2DM. Hence, a ketogenic diet can be recommended for the therapeutic intervention of overweight patients with T2DM.
Topics: Blood Glucose; Body Weight; Diabetes Mellitus, Type 2; Diet, Ketogenic; Glycemic Control; Humans; Overweight; Triglycerides; Weight Loss
PubMed: 36012064
DOI: 10.3390/ijerph191610429 -
Obesity Reviews : An Official Journal... Jul 2021This overview of reviews aimed to summarize the effects of exercise training programs on weight loss, changes in body composition, and weight maintenance in adults with... (Review)
Review
Effect of exercise training on weight loss, body composition changes, and weight maintenance in adults with overweight or obesity: An overview of 12 systematic reviews and 149 studies.
This overview of reviews aimed to summarize the effects of exercise training programs on weight loss, changes in body composition, and weight maintenance in adults with overweight or obesity. A systematic search of systematic reviews and meta-analyses (SR-MAs) published between 2010 and December 2019 was performed. Only SR-MAs of controlled trials were included. The mean difference (MD) or standardized MD (SMD) were extracted from SR-MAs. Twelve SR-MAs (149 studies) were included. Exercise led to a significant weight loss (4 SR-MAs, MDs ranging from -1.5 to -3.5 kg), fat loss (4 SR-MAs, MDs ranging from -1.3 to -2.6 kg) and visceral fat loss (3 SR-MAs, SMDs ranging from -0.33 to -0.56). No difference in weight, fat, and visceral loss was found between aerobic and high-intensity interval training as long as energy expenditure was equal. Resistance training reduced lean mass loss during weight loss (1 SR-MA, MD: 0.8 [95%CI: 0.4-1.3] kg). No significant effect of exercise was found on weight maintenance (1 SR-MA). These findings show favorable effects of exercise training on weight loss and body composition changes in adults with overweight or obesity. Visceral fat loss may lead to benefits for cardiometabolic health. More research is needed to identify training modalities that promote weight maintenance.
Topics: Adult; Body Composition; Body Weight Maintenance; Exercise; Humans; Obesity; Overweight; Systematic Reviews as Topic; Weight Loss
PubMed: 33955140
DOI: 10.1111/obr.13256 -
JAMA Apr 2021Weight loss improves cardiometabolic risk factors in people with overweight or obesity. Intensive lifestyle intervention and pharmacotherapy are the most effective... (Comparative Study)
Comparative Study Randomized Controlled Trial
Effect of Subcutaneous Semaglutide vs Placebo as an Adjunct to Intensive Behavioral Therapy on Body Weight in Adults With Overweight or Obesity: The STEP 3 Randomized Clinical Trial.
IMPORTANCE
Weight loss improves cardiometabolic risk factors in people with overweight or obesity. Intensive lifestyle intervention and pharmacotherapy are the most effective noninvasive weight loss approaches.
OBJECTIVE
To compare the effects of once-weekly subcutaneous semaglutide, 2.4 mg vs placebo for weight management as an adjunct to intensive behavioral therapy with initial low-calorie diet in adults with overweight or obesity.
DESIGN, SETTING, AND PARTICIPANTS
Randomized, double-blind, parallel-group, 68-week, phase 3a study (STEP 3) conducted at 41 sites in the US from August 2018 to April 2020 in adults without diabetes (N = 611) and with either overweight (body mass index ≥27) plus at least 1 comorbidity or obesity (body mass index ≥30).
INTERVENTIONS
Participants were randomized (2:1) to semaglutide, 2.4 mg (n = 407) or placebo (n = 204), both combined with a low-calorie diet for the first 8 weeks and intensive behavioral therapy (ie, 30 counseling visits) during 68 weeks.
MAIN OUTCOMES AND MEASURES
The co-primary end points were percentage change in body weight and the loss of 5% or more of baseline weight by week 68. Confirmatory secondary end points included losses of at least 10% or 15% of baseline weight.
RESULTS
Of 611 randomized participants (495 women [81.0%], mean age 46 years [SD, 13], body weight 105.8 kg [SD, 22.9], and body mass index 38.0 [SD, 6.7]), 567 (92.8%) completed the trial, and 505 (82.7%) were receiving treatment at trial end. At week 68, the estimated mean body weight change from baseline was -16.0% for semaglutide vs -5.7% for placebo (difference, -10.3 percentage points [95% CI, -12.0 to -8.6]; P < .001). More participants treated with semaglutide vs placebo lost at least 5% of baseline body weight (86.6% vs 47.6%, respectively; P < .001). A higher proportion of participants in the semaglutide vs placebo group achieved weight losses of at least 10% or 15% (75.3% vs 27.0% and 55.8% vs 13.2%, respectively; P < .001). Gastrointestinal adverse events were more frequent with semaglutide (82.8%) vs placebo (63.2%). Treatment was discontinued owing to these events in 3.4% of semaglutide participants vs 0% of placebo participants.
CONCLUSIONS AND RELEVANCE
Among adults with overweight or obesity, once-weekly subcutaneous semaglutide compared with placebo, used as an adjunct to intensive behavioral therapy and initial low-calorie diet, resulted in significantly greater weight loss during 68 weeks. Further research is needed to assess the durability of these findings.
TRIAL REGISTRATION
ClinicalTrials.gov Identifier: NCT03611582.
Topics: Adult; Anti-Obesity Agents; Cognitive Behavioral Therapy; Combined Modality Therapy; Diet, Reducing; Double-Blind Method; Female; Glucagon-Like Peptide 1; Glucagon-Like Peptides; Humans; Injections, Subcutaneous; Male; Middle Aged; Obesity; Overweight; Weight Loss
PubMed: 33625476
DOI: 10.1001/jama.2021.1831 -
European Journal of Internal Medicine Nov 2021Weight regain following weight loss is frequent problem that people with obesity face. This weight recidivism is often attributed to the lack of compliance with... (Review)
Review
Weight regain following weight loss is frequent problem that people with obesity face. This weight recidivism is often attributed to the lack of compliance with appropriate food habits and exercise. On the contrary, it is known that body weight and fat mass are regulated by numerous physiological mechanisms, far beyond voluntary food intake and physical exercise. Thus, the aim of this paper is to review the main peripheral and central mechanisms involved in weight regain. Gut hormone secretion profiles impact upon predisposition to weight regain according to an individual variability, although it is recognised a usual pattern of compensatory changes: a reduction in anorectic hormones secretion and an increase in orexigenic hormone. These changes lead to both increased appetite and reward value of food leading to increased energye intake. In addition, resting energy expenditure after weight loss is lower than expected according to body composition changes. This gap between observed and predicted energy expenditure following weight loss is named metabolic adaptation, which has been suggested to explain partly weight regain. This complicated scenario, beyond patient motivation, makes weight regain a challenge in long-term management interventions in patients with obesity.
Topics: Body Weight; Energy Intake; Energy Metabolism; Humans; Obesity; Weight Gain; Weight Loss
PubMed: 33461826
DOI: 10.1016/j.ejim.2021.01.002 -
Nutrients Apr 2022We conducted a systematic review and meta-analysis of randomized clinical trials and pilot trial studies to compare the effectiveness of intermittent fasting (IF) and... (Meta-Analysis)
Meta-Analysis
We conducted a systematic review and meta-analysis of randomized clinical trials and pilot trial studies to compare the effectiveness of intermittent fasting (IF) and continuous calorie restriction (CCR) in overweight and obese people. The parameters included body mass index (BMI), body weight, and other metabolism-related indicators. A systematic search in PubMed, Embase, Cochrane Library, and Web of Science was conducted up to January 2022. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were used to measure the effectiveness. Publication bias was assessed using Egger's test. The stability of the results was evaluated using sensitivity analyses. The significance of body weight change (SMD = -0.21, 95% CI (-0.40, -0.02) = 0.028) was more significant after IF than CCR. There was no significant difference in BMI (SMD = 0.02, 95% CI (-0.16, 0.20) = 0.848) between IF and CCR. These findings suggest that IF may be superior to CCR for weight loss in some respects.
Topics: Body Weight; Caloric Restriction; Fasting; Humans; Overweight; Weight Loss
PubMed: 35565749
DOI: 10.3390/nu14091781 -
Nutrients Nov 2022The practice of fasting recently has been purported to have clinical benefits, particularly as an intervention against obesity and its related pathologies. Although a... (Review)
Review
The practice of fasting recently has been purported to have clinical benefits, particularly as an intervention against obesity and its related pathologies. Although a number of different temporal dietary restriction strategies have been employed in practice, they are generally classified under the umbrella term "intermittent fasting" (IF). IF can be stratified into two main categories: (1) intra-weekly fasting (alternate-day fasting/ADF, twice-weekly fasting/TWF) and (2) intra-daily fasting (early time-restricted eating/eTRE and delayed time-restricted eating/dTRE). A growing body of evidence indicates that IF is a viable alternative to daily caloric restriction (DCR), showing effectiveness as a weight loss intervention. This paper narratively reviews the literature on the effects of various commonly used IF strategies on body weight and body composition when compared to traditional DCR approaches, and draws conclusions for their practical application. A specific focus is provided as to the use of IF in combination with regimented exercise programs and the associated effects on fat mass and lean mass.
Topics: Humans; Body Weight; Body Composition; Caloric Restriction; Weight Loss; Fasting
PubMed: 36501050
DOI: 10.3390/nu14235022 -
Seminars in Cancer Biology Jul 2023Excess body weight is a global health problem due to sedentary lifestyle and unhealthy diet, affecting 2 billion population worldwide. Obesity is a major risk factor for... (Review)
Review
Excess body weight is a global health problem due to sedentary lifestyle and unhealthy diet, affecting 2 billion population worldwide. Obesity is a major risk factor for metabolic diseases. Notably, the metabolic risk of obesity largely depends on body weight distribution, of which visceral adipose tissues but not subcutaneous fats are closely associated with obesity comorbidities, including type 2 diabetes, non-alcoholic fatty liver disease, cardiovascular disease and certain types of cancer. Latest multi-omics and mechanistical studies reported the crucial involvement of genetic and epigenetic alterations, adipokines dysregulation, immunity changes, imbalance of white and brown adipose tissues, and gut microbial dysbiosis in mediating the pathogenic association between visceral adipose tissues and comorbidities. In this review, we explore the epidemiology of excess body weight and the up-to-date mechanism of how excess body weight and obesity lead to chronic complications. We also examine the utilization of visceral fat measurement as an accurate clinical parameter for risk assessment in healthy individuals and clinical outcome prediction in obese subjects. In addition, current approaches for the prevention and treatment of excess body weight and its related metabolic comorbidities are further discussed.
Topics: Humans; Diabetes Mellitus, Type 2; Obesity; Comorbidity; Risk Factors; Diet
PubMed: 36965839
DOI: 10.1016/j.semcancer.2023.03.008 -
Obesity Facts 2021The very low-calorie ketogenic diet (VLCKD) has been recently proposed as an appealing nutritional strategy for obesity management. The VLCKD is characterized by a low... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The very low-calorie ketogenic diet (VLCKD) has been recently proposed as an appealing nutritional strategy for obesity management. The VLCKD is characterized by a low carbohydrate content (<50 g/day), 1-1.5 g of protein/kg of ideal body weight, 15-30 g of fat/day, and a daily intake of about 500-800 calories.
OBJECTIVES
The aim of the current document is to suggest a common protocol for VLCKD and to summarize the existing literature on its efficacy in weight management and weight-related comorbidities, as well as the possible side effects.
METHODS
This document has been prepared in adherence with Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines. Literature searches, study selection, methodology development, and quality appraisal were performed independently by 2 authors and the data were collated by means of a meta-analysis and narrative synthesis.
RESULTS
Of the 645 articles retrieved, 15 studies met the inclusion criteria and were reviewed, revealing 4 main findings. First, the VLCKD was shown to result in a significant weight loss in the short, intermediate, and long terms and improvement in body composition parameters as well as glycemic and lipid profiles. Second, when compared with other weight loss interventions of the same duration, the VLCKD showed a major effect on reduction of body weight, fat mass, waist circumference, total cholesterol and triglyceridemia as well as improved insulin resistance. Third, although the VLCKD also resulted in a significant reduction of glycemia, HbA1c, and LDL cholesterol, these changes were similar to those obtained with other weight loss interventions. Finally, the VLCKD can be considered a safe nutritional approach under a health professional's supervision since the most common side effects are usually clinically mild and easily to manage and recovery is often spontaneous.
CONCLUSIONS
The VLCKD can be recommended as an effective dietary treatment for individuals with obesity after considering potential contra-indications and keeping in mind that any dietary treatment has to be personalized. Prospero Registry: The assessment of the efficacy of VLCKD on body weight, body composition, glycemic and lipid parameters in overweight and obese subjects: a meta-analysis (CRD42020205189).
Topics: Adult; Diet, Ketogenic; Humans; Obesity; Obesity Management; Overweight; Weight Loss
PubMed: 33882506
DOI: 10.1159/000515381 -
Nature Medicine Sep 2023In the STEP-HFpEF trial, semaglutide improved symptoms, physical limitations and exercise function and reduced body weight in patients with obesity phenotype of heart...
In the STEP-HFpEF trial, semaglutide improved symptoms, physical limitations and exercise function and reduced body weight in patients with obesity phenotype of heart failure and preserved ejection fraction (HFpEF). This prespecified analysis examined the effects of semaglutide on dual primary endpoints (change in Kansas City Cardiomyopathy Questionnaire-Clinical Summary Score (KCCQ-CSS) and body weight) and confirmatory secondary endpoints (change in 6-minute walk distance (6MWD), hierarchical composite (death, HF events, change in KCCQ-CSS and 6MWD) and change in C-reactive protein (CRP)) across obesity classes I-III (body mass index (BMI) 30.0-34.9 kg m, 35.0-39.9 kg m and ≥40 kg m) and according to body weight reduction with semaglutide after 52 weeks. Semaglutide consistently improved all outcomes across obesity categories (P value for treatment effects × BMI interactions = not significant for all). In semaglutide-treated patients, improvements in KCCQ-CSS, 6MWD and CRP were greater with larger body weight reduction (for example, 6.4-point (95% confidence interval (CI): 4.1, 8.8) and 14.4-m (95% CI: 5.5, 23.3) improvements in KCCQ-CSS and 6MWD for each 10% body weight reduction). In participants with obesity phenotype of HFpEF, semaglutide improved symptoms, physical limitations and exercise function and reduced inflammation and body weight across obesity categories. In semaglutide-treated patients, the magnitude of benefit was directly related to the extent of weight loss. Collectively, these data support semaglutide-mediated weight loss as a key treatment strategy in patients with obesity phenotype of HFpEF. ClinicalTrials.gov identifier: NCT04788511 .
Topics: Humans; Heart Failure; Stroke Volume; Body Weight; Weight Loss; Obesity; C-Reactive Protein
PubMed: 37635157
DOI: 10.1038/s41591-023-02526-x