Very-low-energy diets and morbidity: a systematic review of longer-term evidence

Eating Disorders In weight-related Therapy (EDIT) Collaboration: rationale and study design

The cornerstone of obesity treatment is behavioural weight management, resulting in significant improvements in cardio-metabolic and psychosocial health. However, there is ongoing concern that dietary interventions used for weight management may precipitate the development of eating disorders. Systematic reviews demonstrate that, while for most participants medically supervised obesity treatment improves risk scores related to eating disorders, a subset of people who undergo obesity treatment may have poor outcomes for eating disorders. This review summarises the background and rationale for the formation of the Eating Disorders In weight-related Therapy (EDIT) Collaboration. The EDIT Collaboration will explore the complex risk factor interactions that precede changes to eating disorder risk following weight management. In this review, we also outline the programme of work and design of studies for the EDIT Collaboration, including expected knowledge gains. The EDIT studies explore risk factors and the interactions between them using individual-level data from international weight management trials. Combining all available data on eating disorder risk from weight management trials will allow sufficient sample size to interrogate our hypothesis: that individuals undertaking weight management interventions will vary in their eating disorder risk profile, on the basis of personal characteristics and intervention strategies available to them. The collaboration includes the integration of health consumers in project development and translation. An important knowledge gain from this project is a comprehensive understanding of the impact of weight management interventions on eating disorder risk.

Position statement on nutrition therapy for overweight and obesity: nutrition department of the Brazilian association for the study of obesity and metabolic syndrome (ABESO-2022)

Obesity is a chronic disease resulting from multifactorial causes mainly related to lifestyle (sedentary lifestyle, inadequate eating habits) and to other conditions such as genetic, hereditary, psychological, cultural, and ethnic factors. The weight loss process is slow and complex, and involves lifestyle changes with an emphasis on nutritional therapy, physical activity practice, psychological interventions, and pharmacological or surgical treatment. Because the management of obesity is a long-term process, it is essential that the nutritional treatment contributes to the maintenance of the individual's global health. The main diet-related causes associated with excess weight are the high consumption of ultraprocessed foods, which are high in fats, sugars, and have high energy density; increased portion sizes; and low intake of fruits, vegetables, and grains. In addition, some situations negatively interfere with the weight loss process, such as fad diets that involve the belief in superfoods, the use of teas and phytotherapics, or even the avoidance of certain food groups, as has currently been the case for foods that are sources of carbohydrates. Individuals with obesity are often exposed to fad diets and, on a recurring basis, adhere to proposals with promises of quick solutions, which are not supported by the scientific literature. The adoption of a dietary pattern combining foods such as grains, lean meats, low-fat dairy, fruits, and vegetables, associated with an energy deficit, is the nutritional treatment recommended by the main international guidelines. Moreover, an emphasis on behavioral aspects including motivational interviewing and the encouragement for the individual to develop skills will contribute to achieve and maintain a healthy weight. Therefore, this Position Statement was prepared based on the analysis of the main randomized controlled studies and meta-analyses that tested different nutrition interventions for weight loss. Topics in the frontier of knowledge such as gut microbiota, inflammation, and nutritional genomics, as well as the processes involved in weight regain, were included in this document. This Position Statement was prepared by the Nutrition Department of the Brazilian Association for the Study of Obesity and Metabolic Syndrome (ABESO), with the collaboration of dietitians from research and clinical fields with an emphasis on strategies for weight loss.

Obesity in South and Southeast Asia-A new consensus on care and management

Obesity is a chronic disease in which the abnormal or excessive accumulation of body fat leads to impaired health and increased risk of mortality and chronic health complications. Prevalence of obesity is rising rapidly in South and Southeast Asia, with potentially serious consequences for local economies, healthcare systems, and quality of life. Our group of obesity specialists from Bangladesh, Brunei Darussalam, India, Indonesia, Malaysia, Philippines, Singapore, Sri Lanka, Thailand, and Viet Nam undertook to develop consensus recommendations for management and care of adults and children with obesity in South and Southeast Asia. To this end, we identified and researched 12 clinical questions related to obesity. These questions address the optimal approaches for identifying and staging obesity, treatment (lifestyle, behavioral, pharmacologic, and surgical options) and maintenance of reduced weight, as well as issues related to weight stigma and patient engagement in the clinical setting. We achieved consensus on 42 clinical recommendations that address these questions. An algorithm describing obesity care is presented, keyed to the various consensus recommendations.

Very low energy diets before nonbariatric surgery: A systematic review and meta-analysis

BACKGROUND

Very low energy diets serve as an intensive approach to weight loss in a short period of time. Although the preoperative use of very low energy diets to optimize patients with obesity before bariatric surgery is well established, the evidence for very low energy diets before other types of surgery remains unclear. The aim of this review was to determine the impact of preoperative very low energy diets on perioperative outcomes in nonbariatric surgery.

METHODS

Medline, EMBASE, CENTRAL, and PubMed were systematically searched from inception through to July 2021. Articles were included if they evaluated very low energy diets use before any type of nonbariatric surgery. The primary outcome was postoperative morbidity. Secondary outcomes included compliance, safety, and preoperative weight loss. A pairwise meta-analyses using inverse variance random effects was performed.

RESULTS

From 792 citations, 13 studies with 395 patients (mean age: 56.5 years, 55.8% female) receiving very low energy diets preoperatively in preparation for nonbariatric surgery were included. Mean duration of preoperative very low energy diets was 6.6 weeks (range, 0.42-17 weeks). Target daily caloric intake ranged from 450 kcal to 1,400 kcal. Compliance with very low energy diets ranged from 94% to 100%. The mean preoperative weight loss ranged from 3.2 kg to 19.2 kg. There were no significant differences in postoperative morbidity (odds ratio, 1.10; 95% confidence interval, 0.64-1.91; P = .72), operative time (standard mean difference -0.35; 95% confidence interval, 1.13-0.43, P = .38), or postoperative length of stay (standard mean difference 0.40, 95% confidence interval -0.11-0.91, P = .12) with very low energy diets.

CONCLUSION

Although the currently available evidence is heterogenous, preoperative very low energy diets are safe, well tolerated, and effectively induce preoperative weight loss in patients undergoing nonbariatric surgery for both benign and malignant disease. Further prospective studies are warranted.

Effects of total diet replacement programs on mental well-being: A systematic review with meta-analyses

This systematic review with meta-analyses assessed the effects of total diet replacement (TDR) programs on mental well-being in clinical trial participants with a body mass index greater than or equal to 25 kg/m² . TDR programs involve replacing all dietary requirements with nutritionally replete formula foods and are generally administered to induce rapid weight loss. To date, it is largely unclear what effects TDR programs may have on mental well-being, particularly in the long-term. To address this, we screened 25,976 references across six databases and extracted 35 publications. These 35 publications provided sufficient data to evaluate the effects of TDR programs on depression, anxiety, stress, positive affect, negative affect, vitality, role-emotional, social functioning, mental health, mental composite summary score, self-esteem, and general psychological health in 24 meta-analyses. Due to the lack of research comparing TDR programs to comparator groups, 22 of our 24 meta-analyses explored change in these mental well-being sub-domains over time in TDR programs without comparators. Specifically, we assessed the change from pre-diet (before the TDR program) to either post-diet (up to and including two months after the TDR program); and/or follow-up (more than two months after the TDR program). For depression and anxiety, we were also able to assess the change from pre-diet to mid-diet (which fell within two weeks of the diet half-way point). The remaining two meta-analyses assessed the difference in depression scores between a TDR group and a food-based comparator group from pre-diet to post-diet and from pre-diet to follow-up. Across all meta-analyses, our results found no marked adverse effects of TDR programs on any mental well-being sub-domain. In fact, clear improvements were observed for depression, anxiety, stress, vitality, role-emotional, and social functioning at post-diet. Interestingly, the improvements for depression, vitality and role-emotional were maintained at follow-up. All improvements were observed in meta-analyses without comparators. While the two comparator-based meta-analyses showed no difference between TDR programs and food-based diets in depression symptoms, there was low statistical power. For all meta-analyses containing three or more independent samples, we constructed prediction intervals to determine the range within which the mean of the true effects may fall for future populations. While these prediction intervals varied between sub-domains, we found that mean depression scores are only likely to increase (i.e., depression will worsen) in less than 3% of future TDR interventions which meet our inclusion/exclusion criteria. Taken together, we concluded that for adults with a body mass index greater than or equal to 25 kg/m² , TDR programs are unlikely to lead to marked adverse effects on mental well-being. These findings do not support the exclusion of participants from trials or interventions involving TDR programs based on concerns that these programs may adversely affect mental well-being. In fact, by excluding these participants, they may be prevented from improving their metabolic health and mental well-being.

Nutrition and physical activity: An Obesity Medicine Association (OMA) Clinical Practice Statement 2022

Background

This Obesity Medicine Association (OMA) Clinical Practice Statement (CPS) on Nutrition and Physical Activity provides clinicians an overview of nutrition and physical activity principles applicable to the care of patients with increased body fat, especially those with adverse fat mass and adiposopathic metabolic consequences.

Methods

The scientific information and clinical guidance is based upon referenced evidence and derived from the clinical perspectives of the authors.

Results

This OMA CPS on Nutrition and Physical Activity provides basic clinical information regarding carbohydrates, proteins, fats (including trans fats, saturated fats, polyunsaturated fats, and monounsaturated fats), general principles of healthful nutrition, nutritional factors associated with improved health outcomes, and food labels. Included are the clinical implications of isocaloric substitution of refined carbohydrates with saturated fats and vice-versa, as well as definitions of low-calorie, very low-calorie, carbohydrate-restricted, and fat-restricted dietary intakes. Specific dietary plans discussed include carbohydrate-restricted diets, fat-restricted diets, very low-calorie diets, the Mediterranean diet, Therapeutic Lifestyle diet, Dietary Approaches to Stop Hypertension (DASH), ketogenic (modified Atkins) diet, Ornish diet, Paleo diet, vegetarian or vegan diet (whole food/plant-based), intermittent fasting/time restricted feeding, and commercial diet programs. This clinical practice statement also examines the health benefits of physical activity and provides practical pre-exercise medical evaluation guidance as well as suggestions regarding types and recommended amounts of dynamic (aerobic) training, resistance (anaerobic) training, leisure time physical activity, and non-exercise activity thermogenesis (NEAT). Additional guidance is provided regarding muscle physiology, exercise prescription, metabolic equivalent tasks (METS), and methods to track physical activity progress.

Conclusion

This Obesity Medicine Association Clinical Practice Statement on Nutrition and Physical Activity provides clinicians an overview of nutrition and physical activity. Implementation of appropriate nutrition and physical activity in patients with pre-obesity and/or obesity may improve the health of patients, especially those with adverse fat mass and adiposopathic metabolic consequences.

Remission of Type 2 Diabetes with Very Low-Calorie Diets-A Narrative Review

Very low-calorie diets (VLCD) are hypocaloric dietary regimens of approximately 400-800 kcal/day that result in 20-30% reductions in body weight, sometimes in just 12-16 weeks. A body of evidence demonstrates that adherence to VLCD in adults with type 2 diabetes (T2D) can result in marked improvements to glycemic control and even full T2D remission, challenging the convention that T2D is a lifelong disease. Although these data are promising, the majority of VLCD studies have focused on weight loss and not T2D remission as a primary endpoint. Moreover, there is a wide range of VLCD protocols and definitions of T2D remission used across these hypocaloric studies. Together the large degree of heterogeneity in VLCD studies, and how T2D remission is defined, leave many gaps in knowledge to efficacy and durability of VLCD approaches for T2D remission. This narrative review examines findings from a body of data from VLCD studies that specifically sought to investigate T2D remission, and discusses the efficacy of VLCD compared to other hypocaloric approaches, and who is likely to benefit from VLCD approaches for T2D remission.

Effects on body weight, eating behavior, and quality of life of a low-energy diet combined with behavioral group treatment of persons with class II or III obesity: A 2-year pilot study

Objective

Obesity is associated with reduced health‐related quality of life (HRQoL). Outcomes of nonsurgical weight loss treatment on HRQoL are inconsistent and it is unclear how much weight reduction, or what type of treatment, is required for significant improvements. This study aimed to evaluate the effects of a lifestyle intervention program on weight, eating behaviors, and HRQoL, and to describe participants' experiences of treatment.

Methods

This 2‐year intervention trial in persons with class II or III obesity comprised a 3‐month liquid low‐energy diet (880 kcal/d) followed by a 3‐month reintroduction to regular foods, combined with behavioral group treatment.

Results

Fifty‐five participants (73% women) were included, mean (SD) age 43.2 (12.4) years, and mean body mass index 42.0 (6.0) kg/m². Mean weight loss at 6, 12, and 24 months was 18.9%, 13.7%, and 7.2%, respectively. Short‐ and long‐term effects on eating behavior were favorable. Twelve of 14 HRQoL domains were improved at 6 months, compared to eight domains at 12 months. After 24 months, 2 of 14 domains, physical and psychosocial functioning, were improved. The treatment program was well accepted by the participants.

Conclusions

Substantial weight loss after 6 months was associated with extensive improvements in HRQoL, comprising the physical, psychosocial, and mental domains. Significant weight regain was observed between 6 and 24 months follow‐up. Modest weight loss after 24 months was associated with moderate improvement in physical functioning and large improvement in psychosocial functioning. The effect on psychosocial functioning is most likely related to both weight loss and behavioral treatment.

A practical guide for the use of very low calorie diets in adults with chronic kidney disease

Obesity is increasingly common in individuals with chronic kidney disease (CKD). Being overweight or obese is associated with both the development and progression of kidney disease. Lifestyle interventions such as the use of very low-calorie diets (VLCD) are being used increasingly for patients with CKD despite warnings from manufacturers that they should be avoided or used with caution. Whilst these diets are effective and can induce rapid weight loss and suppress appetite, their use in patients with chronic and end stage kidney disease is more complex than in the general population. VLCD use in adults with kidney disease requires a more nuanced approach to prescription and closer monitoring for unintended side effects. This review describes the indications and clinical management of patients with CKD undertaking a very low-calorie diet and provides practical guidance regarding how to manage a VLCD, particularly for the latter stages of CKD.

The Efficacy of Energy-Restricted Diets in Achieving Preoperative Weight Loss for Bariatric Patients: a Systematic Review

In bariatric practice, a preoperative weight loss of at least 5% is recommended. However, the hypocaloric diets prescribed vary and no consensus exists. This study examined the efficacy of preoperative diets in achieving 5% weight loss. From a systematic literature search, eight randomised controlled trials (n = 862) were identified. Half of the trials used a "very-low-calorie diet" whilst the rest employed a "low-calorie diet". Only five diets achieved ≥ 5% weight loss over varying durations and energy intakes. By inference, compliance with a 700-1050 kcal (2929-4393 kJ) diet, consisting of moderate carbohydrate, high protein and low/moderate fat, for 3 weeks is likely to achieve 5% weight loss. A low-carbohydrate diet (< 20 g/day) may achieve this target within a shorter duration. Additional research is required to validate these conclusions.

Contemporary approaches to the prevention and management of paediatric obesity: an Australian focus

Of the 34 member countries of the Organisation for Economic Co-operation and Development, obesity prevalence is highest in the United States, with Australia ranking fifth for girls and eighth for boys. Curbing the problem is achievable and can be realised through a combination of smart governance across many sectors, community initiatives, the support of individual efforts, and clinical leadership. At 5 years of age, one in five Australian children are already affected by overweight or obesity; obesity prevention strategies must therefore start before this age. There is strong evidence that reducing screen time and promoting breastfeeding in 0-2-year-olds are effective interventions in the early years. The main behavioural risk factors for obesity are overconsumption of energy-dense, nutrient-poor foods and a lack of physical activity. Emerging evidence suggests poor sleep quality and duration and high amounts of sedentary time also play a role. Systems-based policy actions may change long term obesity prevalence in children by targeting the food environment through nutrition labelling, healthy foods in schools, restricted unhealthy food marketing to children, and fiscal policies to reduce consumption of harmful foods and sugar-sweetened beverages. Macro-environmental factors influence obesity risk. Public transport policy and the built environment (proximity to parks, bike paths, green space, schools and shops) influence play time spent outdoors, walking and cycling. Greater access to parks and playgrounds and active commuting are associated with lower body mass index. Australian interventions have largely employed individual level approaches. These are important, but of limited effectiveness unless priority is also given to policies that reduce obesity-conducive environments. Clinicians can provide anticipatory guidance to support healthy weight and weight-related behaviours, including weight monitoring, early feeding and children's diets, physical activity opportunities, and limited sedentary and screen time. Investigations in children with obesity usually include liver function tests and measuring fasting glucose, lipid and possibly insulin levels. As obesity can be associated with micronutrient deficiencies, it may be prudent to check full blood count and iron, vitamin B12 and vitamin D levels. Endocrinological assessment is usually not needed. Second line investigations may include liver ultrasound, oral glucose tolerance testing and sleep study. Traditional treatment of child and adolescent obesity has focused on family-based, multicomponent (diet, physical activity and behaviour change) interventions, although these lead to small and often short term weight reductions (mean, - 1.45 kg; 95% CI, 1.88 to - 1.02). Nevertheless, these principles remain core interventions in children and adolescents with obesity. A very low energy diet should be considered in adolescents with severe obesity or obesity-related comorbidities, and for adolescents who have not achieved weight loss following a more conventional dietary approach. Pharmacotherapy confers only small reductions in weight; for example, effect size for metformin is - 3.90 kg (95% CI, - 5.86 to - 1.94). Bariatric surgery should be considered in adolescents over 15 years of age with severe obesity (body mass index > 40 kg/m², or > 35 kg/m² in the presence of severe complications).

Bariatric surgery, lifestyle interventions and orlistat for severe obesity: the REBALANCE mixed-methods systematic review and economic evaluation

BACKGROUND

Adults with severe obesity [body mass index (BMI) of ≥ 35 kg/m2] have an increased risk of comorbidities and psychological, social and economic consequences.

OBJECTIVES

Systematically review bariatric surgery, weight-management programmes (WMPs) and orlistat pharmacotherapy for adults with severe obesity, and evaluate the feasibility, acceptability, clinical effectiveness and cost-effectiveness of treatment.

DATA SOURCES

Electronic databases including MEDLINE, EMBASE, PsycINFO, the Cochrane Central Register of Controlled Trials and the NHS Economic Evaluation Database were searched (last searched in May 2017).

REVIEW METHODS

Four systematic reviews evaluated clinical effectiveness, cost-effectiveness and qualitative evidence for adults with a BMI of ≥ 35 kg/m2. Data from meta-analyses populated a microsimulation model predicting costs, outcomes and cost-effectiveness of Roux-en-Y gastric bypass (RYGB) surgery and the most effective lifestyle WMPs over a 30-year time horizon from a NHS perspective, compared with current UK population obesity trends. Interventions were cost-effective if the additional cost of achieving a quality-adjusted life-year is < £20,000-30,000.

RESULTS

A total of 131 randomised controlled trials (RCTs), 26 UK studies, 33 qualitative studies and 46 cost-effectiveness studies were included. From RCTs, RYGB produced the greatest long-term weight change [-20.23 kg, 95% confidence interval (CI) -23.75 to -16.71 kg, at 60 months]. WMPs with very low-calorie diets (VLCDs) produced the greatest weight loss at 12 months compared with no WMPs. Adding a VLCD to a WMP gave an additional mean weight change of -4.41 kg (95% CI -5.93 to -2.88 kg) at 12 months. The intensive Look AHEAD WMP produced mean long-term weight loss of 6% in people with type 2 diabetes mellitus (at a median of 9.6 years). The microsimulation model found that WMPs were generally cost-effective compared with population obesity trends. Long-term WMP weight regain was very uncertain, apart from Look AHEAD. The addition of a VLCD to a WMP was not cost-effective compared with a WMP alone. RYGB was cost-effective compared with no surgery and WMPs, but the model did not replicate long-term cost savings found in previous studies. Qualitative data suggested that participants could be attracted to take part in WMPs through endorsement by their health-care provider or through perceiving innovative activities, with WMPs being delivered to groups. Features improving long-term weight loss included having group support, additional behavioural support, a physical activity programme to attend, a prescribed calorie diet or a calorie deficit.

LIMITATIONS

Reviewed studies often lacked generalisability to UK settings in terms of participants and resources for implementation, and usually lacked long-term follow-up (particularly for complications for surgery), leading to unrealistic weight regain assumptions. The views of potential and actual users of services were rarely reported to contribute to service design. This study may have failed to identify unpublished UK evaluations. Dual, blinded numerical data extraction was not undertaken.

CONCLUSIONS

Roux-en-Y gastric bypass was costly to deliver, but it was the most cost-effective intervention. Adding a VLCD to a WMP was not cost-effective compared with a WMP alone. Most WMPs were cost-effective compared with current population obesity trends.

FUTURE WORK

Improved reporting of WMPs is needed to allow replication, translation and further research. Qualitative research is needed with adults who are potential users of, or who fail to engage with or drop out from, WMPs. RCTs and economic evaluations in UK settings (e.g. Tier 3, commercial programmes or primary care) should evaluate VLCDs with long-term follow-up (≥ 5 years). Decision models should incorporate relevant costs, disease states and evidence-based weight regain assumptions.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016040190.

FUNDING

The National Institute for Health Research Health Technology Assessment programme. The Health Services Research Unit and Health Economics Research Unit are core funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorate.

Willing to go the extra mile: Prospective evaluation of an intensified non-surgical treatment for patients with morbid obesity

BACKGROUND & AIMS

Bariatric surgery has been well established and considered the treatment of choice in morbid obesity. However, some patients refuse surgery because long-term effects have not been fully elucidated, quality of life might change and lifelong supplementation with vitamins and trace elements may be required. Our aim was to exhaust non-surgical treatment modalities and to evaluate such an intensified treatment alternative.

METHODS

A total of 206 patients (mean age = 46 years; BMI = 49 kg/m²) enrolled since 2013 into a non-surgical multimodality obesity treatment program covered by major health insurances were prospectively evaluated over a three year period. The 12-month treatment course comprised 57 h cognitive-behavioral therapy, 53.5 h physical exercise training, and 43.5 h nutritional therapy offered in small groups. Weight loss was induced by a formula-based, very low-calorie diet for 12 weeks in combination with a gastric balloon. The primary outcome was relative weight loss (RWL). Secondary outcome measures were waist-to-hip ratio, blood pressure, antihypertensive drug treatment, anti-diabetic medication, HbA1c, and quality of life.

RESULTS

166 Patients (81%) completed treatment. Mean (±SD) weight loss after 12 months for women and men were 28.8 kg (±14.7) and 33.7 kg (±19.5), respectively, among completers. RWL was 21.9% (±10.0) and excess weight loss (EWL) was 46.9% (±22.2), whereas intention-to-treat analysis revealed a RWL of 20.0% (±10.4) and an EWL of 42.9% (±22.9). Weight loss was accompanied by improved quality of life, lowered HbA1c values, and a significantly reduced need of antihypertensive and diabetes medications over the study period. Three year follow-up data from the first 78 patients (76% follow-up rate) revealed a RWL of 13% (±13.1) and an EWL of 27.2% (±28.8). The majority of patients (51%) maintained a RWL of 10% or more, and 44% had an EWL > 30%.

CONCLUSIONS

In patients with morbid obesity, an intensified non-surgical multimodality treatment program may achieve significant and sustained weight loss accompanied by improvement of disease markers as well as quality of life for at least three years.

Treatment of adolescent obesity

The increased prevalence of adolescent obesity and associated short-term and long-term complications emphasize the need for effective treatment. In this Review, we aim to describe the evidence for, and elements of, behaviour management and adjunctive therapies and highlight the opportunities and challenges presented by obesity management in adolescence. The broad principles of treatment include management of obesity-associated complications; a developmentally appropriate approach; long-term behaviour modification (dietary change, increased physical activity, decreased sedentary behaviours and improved sleep patterns); long-term weight maintenance strategies; and consideration of the use of pharmacotherapy, more intensive dietary therapies and bariatric surgery. Bariatric surgery should be considered in those with severe obesity and be undertaken by skilled bariatric surgeons affiliated with teams experienced in the medical and psychosocial management of adolescents. Adolescent obesity management strategies are more reliant on active participation than those for childhood obesity and should recognize the emerging autonomy of the patient. The challenges in adolescent obesity relate primarily to the often competing demands of developing autonomy and not yet having attained neurocognitive maturity.

Critical review of bariatric surgery, medically supervised diets, and behavioural interventions for weight management in adults

AIMS

Patient selection of weight management treatment option is often guided by a variety of factors. Currently, there is no comprehensive tool to facilitate informed decision-making for patients and clinicians. This article aims to synthesise evidence on the treatment effectiveness, health benefits, risks, and patient experiences of treatment options presently available at the Weight Management Clinic at The Ottawa Hospital (TOH), as a first step towards developing a decision aid.

METHODS

Narrative and systematic reviews published in English between 1999 and 2014 were included that focused on one or more of the following weight management treatments in adults aged 18 years and over: roux-en-y gastric bypass (RYGB), sleeve gastrectomy (SG), medically supervised meal replacement, and behavioural or lifestyle intervention.

RESULTS

Overall, bariatric surgeries have received the greatest research attention and have been associated not only with greater weight loss and health benefit but also with greater risks, complications, and financial cost. Dietary programmes demonstrated weight loss and health benefits to a lesser extent than with surgery but were associated with lower and shorter-term risks and complications. Behavioural and lifestyle interventions have been studied less yet have shown significant, albeit small, weight loss outcomes alone and in combination with dietary or surgical options; they also appear to be the lowest risk interventions. Patient experiences of weight management options are mixed and not well understood.

CONCLUSION

Further research is needed; however, this review identified some general trends related to weight loss outcomes, benefits, risks, and barriers for weight management options that have implications for shared treatment decision-making.

Asthma and dietary intake: an overview of systematic reviews

Epidemiological research on the relationship between diet and asthma has increased in the last decade. Several components found in foods have been proposed to have a series of antioxidant, anti-allergic and anti-inflammatory properties, which can have a protective effect against asthma risk. Several literature reviews and critical appraisals have been published to summarize the existing evidence in this field. In the context of this EAACI Lifestyle and asthma Task Force, we summarize the evidence from existing systematic reviews on dietary intake and asthma, using the PRISMA guidelines. We therefore report the quality of eligible systematic reviews and summarize the results of those with an AMSTAR score ≥32. The GRADE approach is used to assess the overall quality of the existing evidence. This overview is centred on systematic reviews of nutritional components provided in the diet only, as a way to establish what type of advice can be given in clinical practice and to the general population on dietary habits and asthma.

Clinical effectiveness of very-low-energy diets in the management of weight loss: a systematic review and meta-analysis of randomized controlled trials

Guidelines suggest that very-low-energy diets (VLEDs) should be used to treat obesity only when rapid weight loss is clinically indicated because of concerns about rapid weight regain. Literature databases were searched from inception to November 2014. Randomized trials were included where the intervention included a VLED and the comparator was no intervention or an intervention that could be given in a general medical setting in adults that were overweight. Two reviewers characterized the population, intervention, control groups, outcomes and appraised quality. The primary outcome was weight change at 12 months from baseline. Compared with a behavioural programme alone, VLEDs combined with a behavioural programme achieved -3.9 kg [95% confidence interval (CI) -6.7 to -1.1] at 1 year. The difference at 24 months was -1.4 kg (95%CI -2.6 to -0.2) and at 38-60 months was -1.3 kg (95%CI -2.9 to 0.2). Nineteen per cent of the VLED group discontinued treatment prematurely compared with 20% of the comparator groups, relative risk 0.96 (0.56 to 1.66). One serious adverse event, hospitalization with cholecystitis, was reported in the VLED group and none in the comparator group. Very-low-energy diets with behavioural programmes achieve greater long-term weight loss than behavioural programmes alone, appear tolerable and lead to few adverse events suggesting they could be more widely used than current guidelines suggest.

Does Diet-Induced Weight Loss Lead to Bone Loss in Overweight or Obese Adults? A Systematic Review and Meta-Analysis of Clinical Trials

Diet-induced weight loss has been suggested to be harmful to bone health. We conducted a systematic review and meta-analysis (using a random-effects model) to quantify the effect of diet-induced weight loss on bone. We included 41 publications involving overweight or obese but otherwise healthy adults who followed a dietary weight-loss intervention. The primary outcomes examined were changes from baseline in total hip, lumbar spine, and total body bone mineral density (BMD), as assessed by dual-energy X-ray absorptiometry (DXA). Secondary outcomes were markers of bone turnover. Diet-induced weight loss was associated with significant decreases of 0.010 to 0.015 g/cm(2) in total hip BMD for interventions of 6, 12, or 24 (but not 3) months' duration (95% confidence intervals [CIs], -0.014 to -0.005, -0.021 to -0.008, and -0.024 to -0.000 g/cm(2), at 6, 12, and 24 months, respectively). There was, however, no statistically significant effect of diet-induced weight loss on lumbar spine or whole-body BMD for interventions of 3 to 24 months' duration, except for a significant decrease in total body BMD (-0.011 g/cm(2); 95% CI, -0.018 to -0.003 g/cm(2)) after 6 months. Although no statistically significant changes occurred in serum concentrations of N-terminal propeptide of type I procollagen (P1NP), interventions of 2 or 3 months in duration (but not of 6, 12, or 24 months' duration) induced significant increases in serum concentrations of osteocalcin (0.26 nmol/L; 95% CI, 0.13 to 0.39 nmol/L), C-terminal telopeptide of type I collagen (CTX) (4.72 nmol/L; 95% CI, 2.12 to 7.30 nmol/L) or N-terminal telopeptide of type I collagen (NTX) (3.70 nmol/L; 95% CI, 0.90 to 6.50 nmol/L bone collagen equivalents [BCEs]), indicating an early effect of diet-induced weight loss to promote bone breakdown. These data show that in overweight and obese individuals, a single diet-induced weight-loss intervention induces a small decrease in total hip BMD, but not lumbar spine BMD. This decrease is small in comparison to known metabolic benefits of losing excess weight.

Does severe dietary energy restriction increase binge eating in overweight or obese individuals? A systematic review

Severe dietary energy restriction is often used for overweight or obese individuals to achieve rapid weight loss and related health improvements. However, the extent of putative adverse effects on eating behaviour is unknown. We thus systematically searched seven databases for studies that assessed binge eating before and after severe dietary energy restriction (low or very low energy diets) in overweight or obese individuals. Fifteen clinically supervised interventions from 10 publications (nine of which involved only women) were included. Among individuals with clinically relevant pre-treatment binge eating disorder, severe dietary energy restriction significantly decreased binge eating in all four interventions involving this population, at least during the weight loss programme. In contrast, no consistent association between severe dietary energy restriction and the onset of bingeing was found in 11 interventions involving individuals without pre-treatment binge eating disorder, with four such interventions showing significant increases, two showing no change, and five showing significant decreases in binge eating. We conclude that clinically supervised severe dietary energy restriction appears safe and beneficial for overweight or obese individuals with pre-treatment binge eating disorder, and does not necessarily trigger binge eating in those without binge eating disorder.

Bariatric surgery in class I obesity : a Position Statement from the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO)

Class I obesity conveys an increased risk of comorbidities, impairs physical and mental health-related quality of life, and it is associated to an increased psychosocial burden, particularly in women. The need for effective and safe therapies for class I obesity is great and not yet met by nonsurgical approaches. Eligibility to bariatric surgery has been largely based on body mass index (BMI) cut points and limited to patients with more severe obesity levels. However, obese patients belonging to the same BMI class may have very different levels of health, risk, and impact of obesity on quality of life. Individual patients in class I obesity may have a comorbidity burden similar to, or greater than, patients with more severe obesity. Therefore, the denial of bariatric surgery to a patient with class I obesity suffering from a significant obesity-related health burden and not achieving weight control with nonsurgical therapy simply on the basis of the BMI level does not appear to be clinically justified. A clinical decision should be based on a more comprehensive evaluation of the patient's current global health and on a more reliable prediction of future morbidity and mortality. After a careful review of available data about safety and efficacy of bariatric surgery in patients with class I obesity, this panel reached a consensus on ten clinical recommendations.

The neuropeptide Y-ergic system: potential therapeutic target against bone loss with obesity treatments

Obesity is no longer considered to provide protection against osteoporosis. Moreover, treatments for obesity are now suspected of reducing bone mass. With the escalating incidence of obesity, combined with increases in the frequency, duration and intensity of interventions used to combat it, we face a potential increase in health burden due to osteoporotic fractures. The neuropeptide Y-ergic system offers a potential target for the prevention and anabolic treatment of bone loss in obesity, due to its dual role in the regulation of energy homeostasis and bone mass. Although the strongest stimulation of bone mass by this system appears to occur via indirect hypothalamic pathways involving Y2 receptors (one of the five types of receptors for neuropeptide Y), Y1 receptors on osteoblasts (bone-forming cells) induce direct effects to enhance bone mass. This latter pathway may offer a suitable target for anti-osteoporotic treatment while also minimizing the risk of adverse side effects.

Weight loss for women with and without polycystic ovary syndrome following a very low-calorie diet in a community-based setting with trained facilitators for 12 weeks

BACKGROUND

Polycystic ovary syndrome (PCOS) affects between 2% and 26% of reproductive-age women in the UK, and accounts for up to 75% of anovulatory infertility. The major symptoms include ovarian disruption, hyperandrogenism, insulin resistance, and polycystic ovaries. Interestingly, at least half of the women with PCOS are obese, with the excess weight playing a pathogenic role in the development and progress of the syndrome. The first-line treatment option for overweight/obese women with PCOS is diet and lifestyle interventions; however, optimal dietary guidelines are missing. Although many different dietary approaches have been investigated, data on the effectiveness of very low-calorie diets on PCOS are very limited.

MATERIALS AND METHODS

The aim of this paper was to investigate how overweight/obese women with PCOS responded to LighterLife Total, a commercial very low-calorie diet, in conjunction with group behavioral change sessions when compared to women without PCOS (non-PCOS).

RESULTS

PCOS (n=508) and non-PCOS (n=508) participants were matched for age (age ±1 unit) and body mass index (body mass index ±1 unit). A 12-week completers analysis showed that the total weight loss did not differ significantly between PCOS (n=137) and non-PCOS participants (n=137) (-18.5±6.6 kg vs -19.4±5.7 kg, P=0.190). Similarly, the percentage of weight loss achieved by both groups was not significantly different (PCOS 17.1%±5.6% vs non-PCOS 18.2%±4.4%, P=0.08).

CONCLUSION

Overall, LighterLife Total could be an effective weight-loss strategy in overweight/obese women with PCOS. However, further investigations are needed to achieve a thorough way of understanding the physiology of weight loss in PCOS.

Long-term weight loss maintenance and management following a VLCD: a 3-year outcome

BACKGROUND

Effective weight loss treatment is important as obesity has severe health and socioeconomic repercussions. Emerging evidence suggests that rapid initial weight loss results in better long-term weight loss maintenance. This remains controversial and contradicts current recommendations for slower weight loss.

AIM

To determine the effect of a very low calorie diet (VLCD) with group-based behaviour therapy on weight loss and long-term weight management by means of a retrospective database analysis.

METHODS

Data for this retrospective analysis included participants who embarked on the LighterLife Total VLCD programme between 2007 and 2010, and whose weights at baseline and at least 12 months were available (n = 5965).

RESULTS

Data were available for 5965 individuals at 1 year, 2044 at 2 years and 580 at 3 years. At baseline, the majority of individuals were Caucasian (n = 5155), female (n = 5419), ≥ 40 years old (n = 4272), 49% were within the body mass index (BMI) range of 30-35 kg/m(2) while 51% had a BMI > 35 kg/m(2) . The average initial weight of the whole cohort was 99.1 kg (SD 16.6). Initial weight and BMI at entry onto programme, as well as numbers of weeks of weight loss were all significantly associated with weight loss achieved on the first weight loss attempt. Weight lost during the initial weight loss phase was the only factor, which was significantly associated with percentage weight loss maintenance for years 1, 2, and 3.

CONCLUSION

The findings of this retrospective analysis suggest that provided a longer term weight loss management programme is adhered to, large amounts of initial weight loss can result in important longer term weight loss maintenance in motivated individuals.

Weight loss for individuals with type 2 diabetes following a very-low-calorie diet in a community-based setting with trained facilitators for 12 weeks

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

Approximately 80% of people with type 2 diabetes mellitus (T2DM) are overweight or obese. Weight loss produces numerous benefits in T2DM. People with T2DM have difficulty losing and maintaining weight.

WHAT THIS STUDY ADDS

Provision of a very-low-calorie diet (VLCD) with group support and behaviour therapy for patients with T2DM is feasible within a community-based setting with trained facilitators. VLCD approaches for weight management in T2DM can achieve more than 90% of weight loss as compared with obese individuals without T2DM. Identification of the need to investigate the full impact of this approach in patients with T2DM by assessing changes in glycaemia, liver function and medication. Approximately 80% of people with type 2 diabetes mellitus (T2DM) are overweight or obese, and obesity compounds the cardiovascular risk of T2DM. The aim of this retrospective study was twofold: first, to investigate whether a 12-week community-based very-low-calorie diet (VLCD) programme can result in important weight loss; and second, to investigate any potential difference in the weight loss achieved using this community-based approach in individuals with and without T2DM. Three hundred and fifty-five participants with T2DM were matched for age, body mass index (BMI) and gender to participants without T2DM (total cohort comprised 204 males: 506 females (mean ± standard deviation); age (years) 54.0 ± 9.1; BMI (kg m(-2) ) 41.6 ± 8.1; weight (kg) 116.1 ± 25.1). The programme included a daily intake of 550 kcal in addition to group support and behaviour therapy provided by trained facilitators within a community-based setting. After 12 weeks, there was significant weight loss within each group when compared with baseline (T2DM: 115.0 ± 24.4 kg vs. 96.7 ± 21.4 kg, P < 0.0001; non-T2DM: 117.2 ± 25.8 kg vs. 97.3 ± 22.2 kg, P < 0.0001). At 12 weeks, weight change (-18.3 ± 7.3 kg vs. -19.9 ± 7.0 kg, P = 0.012) and BMI change (-6.7 ± 2.9 kg m(-2) vs. -7.1 ± 2.1 kg m(-2) , P = 0.011) were significantly less in the T2DM group when compared with the non-T2DM group. Our results suggest that the use of VLCD approaches for weight management in T2DM can achieve more than 90% of the weight loss seen in obese individuals without T2DM.

The effect of very low-calorie diets on renal and hepatic outcomes: a systematic review

Very low-calorie diets (VLCDs) are an effective means by which to induce clinically significant weight loss. However, their acceptance by health care practitioners and the public is generally lower than that for other nonsurgical weight loss methods. Whilst there is currently little evidence to suggest they have any detrimental effect on hepatic and renal health, data assessing these factors remain limited. We carried out a systematic review of the literature on randomized controlled trials that had a VLCD component and that reported outcomes for hepatic and renal health, published between January 1980 and December 2012. Cochrane criteria were followed, and eight out of 196 potential articles met the inclusion criteria. A total of 548 participants were recruited across the eight studies. All eight studies reported significant weight loss following the VLCD. Changes in hepatic and renal outcomes were variable but generally led to either no change or improvements in either of these. Due to the heterogeneity in the quality and methodology of the studies included, the effect of VLCDs on hepatic and renal outcomes remains unclear at this stage. Further standardized research is therefore required to fully assess the impact of VLCDs on these outcome measures, to better guide clinical practice.