Very low energy diets in the treatment of obesity

Acceptability, Adherence, Safety and Experiences of Low Energy Diets in People With Obesity and Chronic Kidney Disease: A Mixed Methods Study

OBJECTIVES

Obesity is a modifiable risk factor for chronic kidney disease (CKD) progression. Low energy diets (LEDs) have not been adequately studied in people with CKD. This study aimed to explore acceptability, adherence, safety, and experiences of two LED prescriptions in adults living with obesity and CKD.

DESIGN AND METHODS

In a mixed-methods study, obese adults with CKD were prescribed two LEDs (∼800 to 1000 kcal/day each), in a randomised order for 2 weeks each. One diet consisted of four meal replacement products daily (Optifast®, Nestlé Health Science) and the other two pre-prepared frozen meals (Lite n' Easy®, Mitchell's Quality Foods). Participants received weekly dietitian support, completed daily adherence checklists (converted to % of provided meals/replacements consumed) and participated in post-intervention semi-structured interviews to capture their experience.

RESULTS

Nine participants were included (mean age 46.5 ± 14.3 years, estimated glomerular filtration rate 64 ± 26 mL/min/1.73 m2, 4/9 male). Mean self-reported adherence was 88 ± 11% and mean 4-week weight change was -7.3 ± 5.6 kg. Two participants withdrew at week two. Most frequently reported side effects were hunger and headaches. Adverse events of interest included one episode each of hyperkalaemia and hypoglycaemia. No serious adverse events occurred. Four overarching themes of patient experiences were identified: strategies used to adapt, disruption to the norm, individual preferences, and influences on acceptability.

CONCLUSIONS

LEDs were found to be acceptable and safe with high self-reported adherence rates. Future LED trials should include specialist diabetes management, close monitoring for hyperkalaemia and adequate support to assist with managing side effects and dietary and social adjustments.

Levels of hormones regulating appetite and energy homeostasis in response to a 1.5-Year combined lifestyle intervention for obesity

Background: Weight loss can induce changes in appetite-regulating hormone levels, possibly linked to increases in appetite and weight regain. However, hormonal changes vary across interventions. Here, we studied levels of appetite-regulating hormones during a combined lifestyle intervention (CLI: healthy diet, exercise and cognitive behavioral therapy). Methods: We measured levels of long-term adiposity-related hormones (leptin, insulin, high-molecular-weight (HMW) adiponectin) and short-term appetite hormones (PYY, cholecystokinin, gastric-inhibitory polypeptide, pancreatic polypeptide, FGF21, AgRP) in overnight-fasted serum of 39 patients with obesity. Hormone levels were compared between T0 (baseline), T1 (after 10 weeks) and T2 (end of treatment, 1.5 years). T0-T1 hormone changes were correlated with T1-T2 anthropometric changes. Results: Initial weight loss at T1 was maintained at T2 (-5.0%, p < 0.001), and accompanied by decreased leptin and insulin levels at T1 and T2 (all p < 0.05) compared to T0. Most short-term signals were not affected. Only PP levels were decreased at T2 compared to T0 (p < 0.05). Most changes in hormone levels during initial weight loss did not predict subsequent changes in anthropometrics, except for T0-T1 decreases in FGF21 levels and T0-T1 increases in HMW adiponectin levels tended to be associated with larger T1-T2 increases in BMI (p < 0.05 and p = 0.05, respectively). Conclusion: CLI-induced weight loss was associated with changes in levels of long-term adiposity-related hormones towards healthy levels, but not with orexigenic changes in most short-term appetite signals. Our data indicates that the clinical impact of alterations in appetite-regulating hormones during modest weight loss remains questionable. Future studies should investigate potential associations of weight-loss-induced changes in FGF21 and adiponectin levels with weight regain.

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.

Using a Very Low Energy Diet to Achieve Substantial Preconception Weight Loss in Women with Obesity: A Review of the Safety and Efficacy

Obesity in women of reproductive age is common. Emerging evidence suggests that maternal obesity not only increases the risk of adverse pregnancy outcomes but also has an enduring impact on the metabolic health of the offspring. Given this, management of obesity prior to pregnancy is critically important. Almost all international guidelines suggest that women with obesity should aim to achieve weight loss prior to pregnancy. However, current pre-conception weight loss therapies are sub-optimal. Lifestyle modification typically results in modest weight loss. This may assist fertility but does not alter pregnancy outcomes. Bariatric surgery results in substantial weight loss, which improves pregnancy outcomes for the mother but may be harmful to the offspring. Alternative approaches to the management of obesity in women planning pregnancy are needed. Very low energy diets (VLEDs) have been proposed as a possible tool to assist women with obesity achieve weight loss prior to conception. While VLEDs can induce substantial and rapid weight loss, there are concerns about the impact of rapid weight loss on maternal nutrition prior to pregnancy and about inadvertent exposure of the early fetus to ketosis. The purpose of this review is to examine the existing literature regarding the safety and efficacy of a preconception VLED program as a tool to achieve substantial weight loss in women with obesity.

The impact of a structured weight-loss treatment on physical fitness in patients with psoriatic arthritis and obesity compared to matched controls: a prospective interventional study

Objectives

To evaluate the effects of weight loss treatment on physical fitness in patients with psoriatic arthritis (PsA) and obesity compared to matched controls.

Methods

In total, 46 patients with PsA (CASPAR) and BMI ≥ 33 kg/m² and 52 obese persons were included in this 12-month prospective open intervention study with a very low energy diet (640 kcal/day), followed by structured reintroduction of an energy-restricted diet and brief support for physical activity. The primary outcome was muscle strength assessed with hand-grip strength (Grippit) and leg muscle strength (timed stand test). Secondary outcomes were cardiorespiratory fitness, body composition, and physical functioning (SF-36PCS). Outcomes were assessed at baseline, 6 (M6), and 12 months (M12). Nonparametric statistics were used.

Results

Median weight reduction at M6 was 18.9 kg in patients and 23.0 kg in controls, (p = 0.546). At M12, patients’ median weight loss from baseline was 16.1 kg, corresponding with significant loss of total fat mass (− 30.1%), and lean mass (total − 7.0%, arm − 13.7%, and leg − 6.0%). Leg muscle strength improved in patients and controls at M6 (p < 0.001) and remained improved at M12 (p < 0.01), while hand-grip strength was unchanged in both groups. Cardiorespiratory fitness increased in controls at M6 (p = 0.018) and M12 (p = 0.028) but not in patients. Physical functioning improved in both groups at M6 (p < 0.001) and remained improved at M12 (p = 0.008) and (p < 0.01), respectively.

Conclusion

The intervention resulted in positive effects on body weight and total body fat. Despite reduced lean body mass, the muscle strength did not deteriorate in patients with PsA and controls.

Trial registration

ClinicalTrials.gov identifier: NCT02917434, registered on September 21, 2016-retrospectively registered.

Effect of severe compared with moderate energy restriction on physical activity among postmenopausal female adults with obesity: a prespecified secondary analysis of the Type of Energy Manipulation for Promoting optimum metabolic health and body composition in Obesity (TEMPO) Diet randomized controlled Trial

BACKGROUND

An under-explored strategy for increasing physical activity is the dietary treatment of obesity, but empirical evidence is lacking.

OBJECTIVES

We aimed to compare the effects of weight loss via severe as opposed to moderate energy restriction on physical activity over 36 mo.

METHODS

A total of 101 postmenopausal female adults (45-65 y, BMI 30-40 kg/m2, <180 min/wk of structured exercise) were randomly assigned to either 12 mo of moderate energy restriction (25%-35% of energy requirement) with a food-based diet, or a severe intervention involving 4 mo of severe energy restriction (65%-75% of energy requirement) with a total meal replacement diet, followed by 8 mo of moderate energy restriction. Physical activity was encouraged, but no tailored or supervised exercise prescription was provided. Physical activity was assessed with an accelerometer worn for 7 d before baseline (0 mo) and 0.25, 1, 4, 6, 12, 24, and 36 mo after intervention commencement.

RESULTS

Compared with the moderate group, the severe group exhibited greater mean: total volume of physical activity; duration of moderate-to-vigorous-intensity physical activity (MVPA); duration of light-intensity physical activity; step counts, as well as lower mean duration of sedentary time. All these differences (except step counts) were apparent at 6 mo [e.g., 1006 metabolic equivalent of task (MET)-min/wk; 95% CI: 564, 1449 MET-min/wk for total volume of physical activity], and some were also apparent at 4 and/or 12 mo. There were no differences between groups in the 2 other outcomes investigated (self-efficacy to regulate exercise; and proportion of participants meeting the WHO's 2020 Physical Activity Guidelines for MVPA). When the analyses were adjusted for weight at each time point, the differences between groups were either attenuated or abolished.

CONCLUSIONS

Among female adults with obesity, including a dietary component to reduce excess body weight-notably one involving severe energy restriction-could potentially enhance the effectiveness of physical activity interventions.This trial was registered at www.anzctr.org.au as ACTRN12612000651886.

Diet Quality following Total Meal Replacement Compared with Food-Based Weight-Loss Diets in Postmenopausal Women with Obesity: A Secondary Analysis of the TEMPO Diet Trial

BACKGROUND

Severely energy-restricted diets that utilize meal-replacement products are the most effective dietary treatment for obesity. However, there are concerns they may fail to educate individuals on how to adopt a healthy food-based diet after weight loss.

OBJECTIVES

The aim of this research was to compare changes in diet quality following total meal replacement compared with food-based weight-loss diets.

METHODS

In this secondary analysis of a randomized controlled trial, 79 postmenopausal women aged 45-65 y, with a BMI (in kg/m2) of 30-40, were randomly assigned to either a total meal-replacement diet (energy intake restricted by 65-75% relative to requirements) for 16 wks, followed by a food-based diet (energy intake restricted by 25-35% relative to requirements) until 52 wks, or the food-based diet for the entire 52-wk period. Diet quality was scored at baseline and 52 wks using the Healthy Eating Index for Australian Adults, with score changes compared between groups using an independent t test.

RESULTS

Diet quality improved from baseline in both groups, but less so in the total meal-replacement group, with a mean (SD) increase of 3.6 (10.8) points compared with 11.8 (13.9) points in the food-based group, resulting in a mean between-group difference of -8.2 (P = 0.004; 95% CI: -13.8, -2.7) points. This improvement in diet quality within both groups was mostly driven by a reduction in the intake of discretionary foods. Intake remained below the recommendations at 52 wks for 4 of the 5 food groups in both dietary interventions.

CONCLUSIONS

In postmenopausal women with obesity, weight-loss interventions that involve either a total meal-replacement diet or a food-based diet both improve diet quality, however, not sufficiently to meet recommendations. This highlights the importance of addressing diet quality as a part of all dietary weight-loss interventions. This trial is registered with the Australia and New Zealand Clinical Trials Registry as 12612000651886.

The Impact of Restrictive and Non-restrictive Dietary Weight Loss Interventions on Neurobehavioral Factors Related to Body Weight Control: the Gaps and Challenges

PURPOSE OF REVIEW

Restrictive diets, such as low-calorie diets, are difficult to maintain in the long term. For this reason, their popularity has decreased compared to non-restrictive approaches, which instead promote healthy eating strategies. Since both strategies may entail different neurobiological mechanisms, this review will examine the current evidence on the effects of restrictive and non-restrictive interventions on neurobehavioral factors.

RECENT FINDINGS

Restrictive diets appear to improve eating behaviors, and the evidence reviewed argues against the notion that they may worsen the severity of binge eating. Moreover, they may lead to short-term changes in brain structure and improvements in cerebrovascular markers which, in turn, could impact eating behaviors. Non-restrictive interventions may have a positive effect on weight management and eating behaviors. However, evidence of their neural effects is scarce. Small sample sizes, short follow-ups, and the absence of control groups are limitations of the studies targeting both interventions. Rigorous long-term randomized studies are needed to examine the neurobehavioral effects of restrictive and non-restrictive approaches.

Dietary interventions for obesity: clinical and mechanistic findings

Dietary modification is central to obesity treatment. Weight loss diets are available that include various permutations of energy restriction, macronutrients, foods, and dietary intake patterns. Caloric restriction is the common pathway for weight reduction, but different diets may induce weight loss by varied additional mechanisms, including by facilitating dietary adherence. This narrative Review of meta-analyses and select clinical trials found that lower-calorie diets, compared with higher-calorie regimens, reliably induced larger short-term (<6 months) weight losses, with deterioration of this benefit over the long term (>12 months). Few significant long-term differences in weight loss were observed for diets of varying macronutrient composition, although some regimens were found to have short-term advantages (e.g., low carbohydrate versus low fat). Progress in improving dietary adherence, which is critical to both short- and long-term weight loss, could result from greater efforts to identify behavioral and metabolic phenotypes among dieters.

Current Perspectives on the Role of Very-Low-Energy Diets in the Treatment of Obesity and Type 2 Diabetes in Youth

In both developed and developing countries, pediatric obesity and type 2 diabetes are an increasing public health concern: globally 5.6% of girls and 7.8% of boys aged ≥5 years have obesity. The incidence of type 2 diabetes has increased in youth in recent decades and disproportionately affects those from ethnic/racial minority groups and disadvantaged backgrounds. For the treatment of both conditions, conventional lifestyle intervention is frequently ineffective, access to bariatric surgery is very limited and many young people are unsuitable or unwilling to undergo surgery. A very-low-energy diet (VLED) provides a viable alternative and may be effective for weight reduction and improved glycemic control in youth, based on one systematic review. In particular, in the treatment of type 2 diabetes, a chart review and a pilot study both demonstrated that a VLED can reduce the requirement for medications, including insulin, and lead to the remission of diabetes. However, long-term follow-up and safety data remain limited and therefore a VLED is inconsistently recommended by clinical practice guidelines for the treatment of pediatric obesity and type 2 diabetes. In clinical practice, VLED use in children and adolescents is uniquely challenging due to intolerance of expected side effects, difficulty adhering to the highly restrictive diet and difficulty with behaviour change within the current social context and environment. Ultimately, more research, including larger, longer-term trials with comprehensive safety monitoring are required to strengthen the evidence base. This would inform clinical practice guidelines, which may facilitate more widespread utilization of VLED programs in the management of obesity and type 2 diabetes in youth.

Exploring the highs and lows of very low carbohydrate high fat diets on weight loss and diabetes- and cardiovascular disease-related risk markers: A systematic review

AIM

Very low carbohydrate high fat diets (VLCHF) are increasingly popular for weight loss and diabetes management, but the risk implications of long-term adherence to a high-fat-diet remain unclear, especially in high-risk populations. This review aimed to examine adherence, weight loss, diabetes- and cardiovascular disease (CVD)-related risk markers in adults consuming VLCHF diets.

METHODS

Online databases were searched for randomised controlled trials ≥3 months duration that met a pre-defined macronutrient prescription: VLCHF ≤25%E carbohydrate, >35%E fat; low fat (LF) ≥45%E carbohydrate, ≤30%E fat; and reported energy, saturated fat (SFA), weight, blood glucose, cholesterol and blood pressure (BP). Studies were excluded if the macronutrient prescription was not targeted (n = 32); not met (n = 17) or not reported (n = 13).

RESULTS

Eight studies included: 1217 commenced; 922 completed overweight and obese adults. Diets were isocaloric moderately energy-restricted, closely monitored with ongoing support from dietitians, physicians, and/or nurses. Four studies reported non-adherence beyond 3 months (n = 3) and 6 months (n = 1) despite interventions of 12, 15 and 24 months. VLCHF diets were high in fat and SFA (fat 49%-56%E; SFA 11%-21%E) compared to LF diets (fat 13%-29%E; SFA 5%-11%E). All groups achieved significant weight loss and improvements in BP and blood glucose. LDL-C reduction favoured LF, P < .05; increased HDL-C and reduced triglyceride levels favoured VLCHF, P < .05.

CONCLUSIONS

VLCHF and LF diets with moderate energy restriction demonstrate similar weight loss and improvements to BP to 3 months. However, adherence is likely poor without intensive support from health professionals. Dietary SFA should be monitored to ensure recommended intakes, but longer-term studies with high adherence are required to confirm the level of CVD-risk and potential harms.

Nocturnal eating but not binge eating disorder is related to less 12 months' weight loss in men and women with severe obesity: A retrospective cohort study

There is a paucity of studies on the frequency of binge-eating disorder (BED) and nocturnal eating (NE) and their potential role as barriers in non-surgical weight loss treatment in subjects with severe obesity (body mass index [BMI] ≥35 kg m² ). The aim was to identify BED and NE, and their effect on weight loss treatment. In total, 1132 (727 women, 405 men), BMI ~41 kg/m² were patients in a 12-month weight loss programme at a specialist clinic. The questionnaire for eating and weight patterns-revised was completed by the patients before start of treatment. BED was diagnosed in 5.1% of men and 12.4% of women. NE prevalence was 13.5% and 12.7%, respectively. Mean (±SEM) 12-month weight loss was less in patients with NE compared to those without (-11.0 ± 1.5 vs -14.6 ± 0.7 kg, P = .008) but did not differ in patients with and without BED, (-12.3 ± 1.9 vs -14.2 ± 0.6 kg, P = .24). Factors associated with dropout were BED (odds ratio, OR 1.57, 95% confidence interval (CI) 1.14-2.17; P = .006) and previous weight loss attempts (OR 1.35, 95% CI 1.0-1.7; P = .02). BED did not seem to hinder weight loss whereas NE resulted in less weight loss in patients with severe obesity who completed a 12-month treatment programme. Previous weight loss attempts affect both dropout and ability to lose weight.

Urine dipsticks are not accurate for detecting mild ketosis during a severely energy restricted diet

Background

Detection of the mild ketosis induced by severely energy‐restricted diets may be a clinically useful way to monitor and promote dietary adherence. Mild ketosis is often assessed using urine dipsticks, but accuracy for this purpose has not been tested.

Objective

To determine the accuracy of urine dipsticks to detect mild ketosis during adherence to a severely energy‐restricted diet.

Methods

Two hundred and sixty three (263) fasting urine and 263 fasting blood samples were taken from 50 women (mean [standard deviation, SD] age 58.0 [4.3] years and body mass index 34.3 [2.4] kg/m²) before and at six time points during or for up to 10 weeks after 16 weeks of severe energy restriction, achieved with a total meal replacement diet. The amount of ketones (acetoacetate) in the urine was classified as ‘0 (Negative)’, ‘+/− (Trace)’, ‘+ (Weak)’ or ‘++ (Medium)’ by urine dipsticks (Ketostix, Bayer). The concentration of ketones (β‐hydroxybutyrate) in the blood was measured with our reference method, a portable ketone monitor (FreeStyle Optium, Abbott). The diagnostic accuracy of the urine dipsticks was assessed from the percent of instances when a person was actually ‘in ketosis’ (as defined by a blood β‐hydroxybutyrate concentration at or above three different thresholds) that were also identified by the urine dipsticks as being from a person in ketosis (the percent ‘true positives’ or sensitivity), as well as the percent of instances when a person was not in ketosis (as defined by the blood monitor result) was correctly identified as such with the urine dipstick (the percent ‘true negatives’ or specificity). Thresholds of ≥0.3mM, ≥0.5mM or ≥1.0mM were selected, because mean blood concentrations of β‐hydroxybutyrate during ketogenic diets are approximately 0.5mM. Sensitivity and specificity were then used to generate receiver operating characteristic curves, with the area under these curves indicating the ability of the dipsticks to correctly identify people in ketosis (1 = perfect results, 0.5 = random results).

Results

At threshold blood β‐hydroxybutyrate concentrations of ≥0.3mM, ≥0.5mM and ≥1.0mM, the sensitivity of the urine dipsticks was 35%, 52% and 76%; the specificity was 100%, 97% and 78%; and the area under the receiver operating characteristic curves was 0.67, 0.74 and 0.77, respectively. These low levels of sensitivity mean that 65%, 48% or 24% of the instances when a person was in ketosis were not detected by the urine dipsticks.

Conclusion

Urine dipsticks are not an accurate or clinically useful means of detecting mild ketosis in people undergoing a severely energy‐restricted diet and should thus not be recommended in clinical treatment protocols. If monitoring of mild ketosis is indicated (eg, to monitor or help promote adherence to a severely energy‐restricted diet), then blood monitors should be used instead.

Deregulated Serotonin Pathway in Women with Morbid Obesity and NAFLD

Non-alcoholic fatty liver disease (NAFLD) extends from simple steatosis (SS) to non-alcoholic steatohepatitis (NASH). Peripheral serotonin (5-HT) has become as an important regulator of different metabolic pathways. 5-HT has been related to obesity and lipid accumulation in the liver. The objective of this study was to assess the relationship between the 5-HT signaling pathway and the degree of NAFLD, as well as to investigate whether peripheral 5-HT levels are related to the hepatic and jejunal mRNA abundance of serotonin receptors (HTR) in a cohort of women with morbid obesity (MO) and NAFLD. ELISA was used to quantify the serum 5-HT from normal-weight subjects (n = 26) and patients with MO (n = 58). We used RTq-PCR analysis to evaluate the relative expression of HTR in women with MO with normal liver (n = 22), SS (n = 21), and NASH (n = 15). The 5-HT was diminished in women with MO under a hypocaloric diet, regardless of the presence of NAFLD. Additionally, we report a negative correlation of 5-HT levels with metabolic syndrome criteria, suggesting that serotonin may have a protective role in obesity. Additionally, the hepatic expression of HTR2A and HTR2B were decreased in women with MO and NAFLD, but no significant differences in the HTR jejunal expression according to the presence of NAFLD were found.

Effect of Weight Loss via Severe vs Moderate Energy Restriction on Lean Mass and Body Composition Among Postmenopausal Women With Obesity: The TEMPO Diet Randomized Clinical Trial

IMPORTANCE

Severely energy-restricted diets are the most effective dietary obesity treatment. However, there are concerns regarding potential adverse effects on body composition.

OBJECTIVE

To compare the long-term effects of weight loss via severe vs moderate energy restriction on lean mass and other aspects of body composition.

DESIGN, SETTING, AND PARTICIPANTS

The Type of Energy Manipulation for Promoting Optimum Metabolic Health and Body Composition in Obesity (TEMPO) Diet Trial was a 12-month, single-center, randomized clinical trial. A total of 101 postmenopausal women, aged 45 to 65 years with body mass index (calculated as weight in kilograms divided by height in meters squared) from 30 to 40, who were at least 5 years after menopause, had fewer than 3 hours of structured physical activity per week, and lived in the Sydney metropolitan area of New South Wales, Australia, were recruited between March 2013 and July 2016. Data analysis was conducted between October 2018 and August 2019.

INTERVENTION

Participants were randomized to either 12 months of moderate (25%-35%) energy restriction with a food-based diet (moderate intervention) or 4 months of severe (65%-75%) energy restriction with a total meal replacement diet followed by moderate energy restriction for an additional 8 months (severe intervention). Both interventions had a prescribed protein intake of 1.0 g/kg of actual body weight per day, and physical activity was encouraged but not supervised.

MAIN OUTCOMES AND MEASURES

The primary outcome was whole-body lean mass at 12 months after commencement of intervention. Secondary outcomes were body weight, thigh muscle area and muscle function (strength), bone mineral density, and fat mass and distribution, measured at 0, 4, 6, and 12 months.

RESULTS

A total of 101 postmenopausal women were recruited (mean [SD] age, 58.0 [4.2] years; mean [SD] weight, 90.8 [9.1] kg; mean [SD] body mass index, 34.4 [2.5]). Compared with the moderate group at 12 months, the severe group lost more weight (effect size, -6.6 kg; 95% CI, -8.2 to -5.1 kg), lost more whole-body lean mass (effect size, -1.2 kg; 95% CI, -2.0 to -0.4 kg), and lost more thigh muscle area (effect size, -4.2 cm2; 95% CI, -6.5 to -1.9 cm2). However, decreases in whole-body lean mass and thigh muscle area were proportional to total weight loss, and there was no difference in muscle (handgrip) strength between groups. Total hip bone mineral density (effect size, -0.017 g/cm2; 95% CI, -0.029 to -0.005 g/cm2), whole-body fat mass (effect size, -5.5 kg; 95% CI, -7.1 to -3.9 kg), abdominal subcutaneous adipose tissue (effect size, -1890 cm3; 95% CI, -2560 to -1219 cm3), and visceral adipose tissue (effect size, -1389 cm3; 95% CI, -1748 to -1030 cm3) loss were also greater for the severe group than for the moderate group at 12 months.

CONCLUSIONS AND RELEVANCE

Severe energy restriction had no greater adverse effect on relative whole-body lean mass or handgrip strength compared with moderate energy restriction and was associated with 2-fold greater weight and fat loss over 12 months. However, there was significantly greater loss of total hip bone mineral density with severe vs moderate energy restriction. Therefore, caution is necessary when implementing severe energy restriction in postmenopausal women, particularly those with osteopenia or osteoporosis.

TRIAL REGISTRATION

anzctr.org.au Identifier: 12612000651886.

Weight loss improves disease activity in patients with psoriatic arthritis and obesity: an interventional study

Background

Obesity is over-represented in patients with psoriatic arthritis (PsA) and associated with higher disease activity, poorer effect of treatment and increased cardiovascular morbidity. Studies on the effects of weight loss are however needed. This study aimed to prospectively study the effects of weight loss treatment with very low energy diet (VLED) on disease activity in patients with PsA (CASPAR criteria) and obesity (body mass index BMI ≥ 33 kg/m²).

Methods

VLED (640 kcal/day) was taken during 12–16 weeks, depending on pre-treatment BMI. Afterwards, an energy-restricted diet was gradually reintroduced. Weight loss treatment was given within a structured framework for support and medical follow-up.

Treatment with conventional synthetic and/or biologic disease-modifying anti-rheumatic drugs was held constant from 3 months before, until 6 months after baseline.

Patients were assessed with BMI, 66/68 joints count, Leeds enthesitis index, psoriasis body surface area (BSA), questionnaires and CRP at baseline, 3 and 6 months. Primary outcome was the percentage of patients reaching minimal disease activity (MDA) and secondary outcomes were reaching Psoriatic Arthritis Response Criteria (PsARC) and American College of Rheumatology (ACR) response criteria.

Results

Totally 41/46 patients completed the study, 63% women, median age 54 years (IQR 48–62). At baseline increased BMI was associated with higher disease activity and poorer function.

The median weight loss was 18.7 kg (IQR 14.6–26.5) or 18.6% (IQR 14.7–26.3) of the baseline weight. A majority of the disease activity parameters improved significantly after weight loss, including 68/66 tender/swollen joints count, CRP, BSA, Leeds enthesitis index, HAQ and patient VAS for global health, pain and fatigue. A larger weight loss resulted in more improvement in a dose-response manner. The percentage of patients with MDA increased from 29 to 54%, (p = 0.002). PsARC was reached by 46.3%. The ACR 20, 50 and 70 responses were 51.2%, 34.1% and 7.3% respectively.

Conclusions

Short-term weight loss treatment with VLED was associated with significant positive effects on disease activity in joints, entheses and skin in patients with PsA and obesity. The study supports the hypothesis of obesity as a promotor of disease activity in PsA.

Trial registration

ClinicalTrials.gov identifier: NCT02917434, registered on September 21, 2016—retrospectively registered

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1810-5) contains supplementary material, which is available to authorized users.

Rationale and Protocol for a Randomized Controlled Trial Comparing Fast versus Slow Weight Loss in Postmenopausal Women with Obesity-The TEMPO Diet Trial

Very low energy diets (VLEDs), commonly achieved by replacing all food with meal replacement products and which result in fast weight loss, are the most effective dietary obesity treatment available. VLEDs are also cheaper to administer than conventional, food-based diets, which result in slow weight loss. Despite being effective and affordable, these diets are underutilized by healthcare professionals, possibly due to concerns about potential adverse effects on body composition and eating disorder behaviors. This paper describes the rationale and detailed protocol for the TEMPO Diet Trial (Type of Energy Manipulation for Promoting optimal metabolic health and body composition in Obesity), in a randomized controlled trial comparing the long-term (3-year) effects of fast versus slow weight loss. One hundred and one post-menopausal women aged 45–65 years with a body mass index of 30–40 kg/m² were randomized to either: (1) 16 weeks of fast weight loss, achieved by a total meal replacement diet, followed by slow weight loss (as for the SLOW intervention) for the remaining time up until 52 weeks (“FAST” intervention), or (2) 52 weeks of slow weight loss, achieved by a conventional, food-based diet (“SLOW” intervention). Parameters of body composition, cardiometabolic health, eating disorder behaviors and psychology, and adaptive responses to energy restriction were measured throughout the 3-year trial.

Strategies to Improve Adherence to Dietary Weight Loss Interventions in Research and Real-World Settings

Dietary interventions are the cornerstone of obesity treatment. The optimal dietary approach to weight loss is a hotly debated topic among health professionals and the lay public alike. An emerging body of evidence suggests that a higher level of adherence to a diet, regardless of the type of diet, is an important factor in weight loss success over the short and long term. Key strategies to improve adherence include designing dietary weight loss interventions (such as ketogenic diets) that help to control the increased drive to eat that accompanies weight loss, tailoring dietary interventions to a person’s dietary preferences (and nutritional requirements), and promoting self-monitoring of food intake. The aim of this paper is to examine these strategies, which can be used to improve adherence and thereby increase the success of dietary weight loss interventions.

The effects of intermittent compared to continuous energy restriction on glycaemic control in type 2 diabetes; a pragmatic pilot trial

AIMS

Weight loss improves glycaemic control in type 2 diabetes mellitus (T2DM). However, as achieving and maintaining weight loss is difficult, alternative strategies are needed. Our primary aim was to investigate the effects of intermittent energy restriction (IER) compared to continuous energy restriction (CER) on glycated haemoglobin A1c (HbA1c). Secondary aims were to assess effects on weight loss, body composition, medication changes and subjective measures of appetite. Using a 2-day IER method, we expected equal improvements to HbA1c and weight in both groups.

METHOD

Sixty-three overweight or obese participants (BMI 35.2±5kg/m²) with T2DM (HbA1c 7.4±1.3%) (57mmol/mol) were randomised to a 2-day severe energy restriction (1670-2500kJ/day) with 5days of habitual eating, compared to a moderate CER diet (5000-6500kJ/day) for 12weeks.

RESULTS

At 12weeks HbA1c (-0.7±0.9% P<0.001) and percent body weight reduction (-5.9±4% P<0.001) was similar in both groups with no group by time interaction. Similar reductions were also seen for medication dosages, all measures of body composition and subjective reports of appetite.

CONCLUSIONS

In this pilot trial, 2days of IER compared with CER resulted in similar improvements in glycaemic control and weight reduction offering a suitable alternative treatment strategy.

Feasibility of a brief, intensive weight loss intervention to improve reproductive outcomes in obese, subfertile women: a pilot study

OBJECTIVE

To evaluate the feasibility of a brief, intensive weight loss intervention (IWL) to improve reproductive outcomes in obese subfertile women.

DESIGN

Pilot study of IWL versus standard-of-care nutrition counseling (SCN).

SETTING

Single-site, academic institution.

PATIENT(S)

Obese women (body mass index, 35-45 kg/m2) with anovulatory subfertility.

INTERVENTION(S)

Women were rigorously prescreened to rule out secondary causes of subfertility. Eligible women were randomized to IWL or SCN. IWL consisted of 12 weeks of very-low-energy diet (800 kcal/day) + 4 weeks of a low-calorie conventional food-based diet (CFD) to promote 15% weight loss. SCN consisted of 16 weeks of CFD to promote ≥5% weight loss. Women were transitioned to weight maintenance diets and referred back to reproductive endocrinology for ovulation induction.

MAIN OUTCOME MEASURE(S)

Feasibility of recruitment, randomization, intervention implementation, and retention.

RESULT(S)

Thirty-nine women were screened; 25 (64%) were eligible to participate, and 14 of those eligible (56%) agreed to be randomized, seven in each group. One withdrew from the IWL group and two from the SCN group. Percent weight loss was greater in the IWL group than in the SCN group (13% ± 5% vs. 4% ± 4%). Three of six women in the IWL group conceived and delivered term pregnancies. No pregnancies occurred in the SCN group.

CONCLUSION(S)

After rigorous screening, 44% of eligible women completed the study. IWL was associated with greater percentage weight loss and improvements in insulin sensitivity.

CLINICAL TRIAL REGISTRATION

NCT01894074.

Comparison of Very Low Energy Diet Products Available in Australia and How to Tailor Them to Optimise Protein Content for Younger and Older Adult Men and Women

Very low energy diets (VLED) are efficacious in inducing rapid weight loss but may not contain adequate macronutrients or micronutrients for individuals with varying nutritional requirements. Adequate protein intake during weight loss appears particularly important to help preserve fat free mass and control appetite, and low energy and carbohydrate content also contributes to appetite control. Therefore, the purpose of this study was to compare the nutritional content (with a focus on protein), nutritional adequacy and cost of all commercially-available VLED brands in Australia. Nutritional content and cost were extracted and compared between brands and to the Recommended Dietary Intake (RDI) or adequate intake (AI) of macronutrients and micronutrients for men and women aged 19-70 years or >70 years. There was wide variability in the nutritional content, nutritional adequacy and cost of VLED brands. Most notably, even brands with the highest daily protein content, based on consuming three products/day (KicStart™ and Optislim(®), ~60 g/day), only met estimated protein requirements of the smallest and youngest women for whom a VLED would be indicated. Considering multiple options to optimise protein content, we propose that adding pure powdered protein is the most suitable option because it minimizes additional energy, carbohydrate and cost of VLEDs.

Alternate-day versus daily energy restriction diets: which is more effective for weight loss? A systematic review and meta-analysis

Background

Alternate‐day‐fasting (ADF) has been proposed as an effective dieting method. Studies have found that it also can increase life span in rodents, and reduce inflammation in humans. The aim of this paper was to systematically review the efficacy of ADF compared to very‐low‐calorie dieting (VLCD) in terms of weight loss, and reduction of fat mass and fat‐free mass.

Methods

Systematic review: PubMed literature searches were performed. Fixed review procedures were applied. Studies were evaluated for quality. Twenty‐eight studies were included. Meta‐analysis: 10/28 studies (four ADF and six matched VLCD) were further analyzed.

Results

After adjustment for BMI and duration, there was no significant difference in mean body weight loss (VLCD 0.88 kg more weight loss than ADF, 95% CI: −4.32, 2.56) or fat‐free mass (VLCD 1.69 kg more fat‐free mass loss than ADF, 95% CI: −3.62, 0.23); there was a significant difference observed in fat mass (ADF 3.31 kg more fat mass loss than VLCD, 95% CI: 0.05, 6.56). Meta‐analysis showed that, among ADF studies, the pooled change in body weight, fat mass and fat‐free mass was 4.30 kg (95% CI: 3.41, 5.20), 4.06 kg (95% CI: 2.99, 5.13) and 0.72 kg (95% CI: −0.07, 1.51), respectively, while among VLCD studies, the pooled change was 6.28 kg (95% CI: 6.08, 6.49), 4.22 kg (95% CI: 3.95, 4.50) and 2.24 kg (95% CI: 1.95, 2.52), respectively.

Conclusions

Our results from both the systematic review and the meta‐analysis suggest that ADF is an efficacious dietary method, and may be superior to VLCD for some patients because of ease of compliance, greater fat‐mass loss and relative preservation of fat‐free mass. Head‐to‐head randomized clinical trials are needed to further assess relative efficacy of these two approaches.

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.

Weight loss predictability by plasma metabolic signatures in adults with obesity and morbid obesity of the DiOGenes study

OBJECTIVE

Aim is to predict successful weight loss by metabolic signatures at baseline and to identify which differences in metabolic status may underlie variations in weight loss success.

METHODS

In DiOGenes, a randomized, controlled trial, weight loss was induced using a low-calorie diet (800 kcal) for 8 weeks. Men (N = 236) and women (N = 431) as well as groups with overweight/obesity and morbid obesity were studied separately. The relation between the metabolic status before weight loss and weight loss was assessed by stepwise regression on multiple data sets, including anthropometric parameters, NMR-based plasma metabolites, and LC-MS-based plasma lipid species.

RESULTS

Maximally, 57% of the variation in weight loss success can be predicted by baseline parameters. The most powerful predictive models were obtained in subjects with morbid obesity. In these models, the metabolites most predictive for weight loss were acetoacetate, triacylglycerols, phosphatidylcholines, specific amino acids, and creatine and creatinine. This metabolic profile suggests that high energy metabolism activity results in higher amounts of weight loss.

CONCLUSIONS

Possible predictive (pre-diet) markers were found for amount of weight loss for specific subgroups.

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.

Variety, palatability, and obesity

Among the key characteristics of the Western obesogenic food environment is a highly palatable and varied food supply. Laboratory investigations of eating behavior in both humans and animals established key roles for palatability and variety in stimulating appetite, delaying satiety, and promoting excessive energy intake. There is a robust effect of food palatability and variety on short-term food intake, and increased variety and palatability also cause weight gain in animal models. However, laboratory paradigms do not replicate the complexities of eating in a natural setting, and there is a shortage of evidence to estimate the magnitude of effects on weight in humans. There are substantial individual differences in susceptibility to the palatability effect and this may be a key determinant in individual vulnerability to weight gain. The understanding of pathways through which palatability and variety can affect eating is advancing, and epidemiologic and intervention studies are needed to translate laboratory findings into applications in public health or clinical domains, and to establish whether there is a role for greater regulation of the food environment in tackling increases in obesity.

Does weight loss in overweight or obese women improve fertility treatment outcomes? A systematic review

This systematic review assessed the effect of weight loss in overweight and/or obese women undergoing assisted reproductive technology (ART) on their subsequent pregnancy outcome. Weight losses achieved by diet and lifestyle changes, very-low-energy diets, non-surgical medical interventions and bariatric surgery translated into significantly increased pregnancy rates and/or live birth in overweight and/or obese women undergoing ART in 8 of the 11 studies reviewed. In addition, regularization of the menstrual pattern, a decrease in cancellation rates, an increase in the number of embryos available for transfer, a reduction in the number of ART cycles required to achieve pregnancy and a decrease in miscarriage rates were reported. There were also a number of natural conceptions in five of the six studies that reported this outcome. Non-surgical medical weight loss procedures and bariatric surgery induced the greatest weight losses, but their use, as well as that of very-low-energy diets, for weight loss prior to ART requires careful consideration. While the overall quality of the studies included in this review was poor, these results support the clinical recommendation of advising overweight and/or obese women to lose weight prior to ART. Prospective randomized controlled trials are required to establish efficacious evidence-based guidelines for weight loss interventions in overweight and/or obese women prior to ART treatment.

Combination of very low energy diets and pharmacotherapy in the treatment of obesity: meta-analysis of published data

Obesity has reached epidemic proportions globally, with more than 1 billion adults overweight - at least 300 million of them clinically obese - and is a major contributor to the global burden of chronic disease (heart disease and diabetes) and disability. The aim of the study was to perform a systematic review and meta-analysis of published data on the combination of very low energy diets also known as very low calorie diets and pharmacotherapy for its effectiveness in the treatment of obesity. A MEDLINE (Pubmed) search from 1970 to 2009 using multiple combinations of the relevant terms was carried out; the matching articles were also searched for additional references. Meta-analysis tools were used to summarize results. Only randomized controlled trials that compared pharmacotherapy with placebo after a very low energy diet period were selected, and six articles were finally considered to be appropriate for evaluation. The combination of very low energy diet and pharmacotherapy was found to be effective for people with obesity in clinical trials. The net effect of 6.1 kg placebo subtracted weight loss after 1 year represents a clinically meaningful result that is comparable with the effect of drugs given at the start of a weight loss programme. The present meta-analysis contributes to the understanding that combination therapies are expected to achieve greater weight loss than monotherapy; grasping this understanding, researcher has introduced newer anti-obesity pharmacological approaches have embraced combination therapies.

Different dietary strategies for weight loss in obesity: role of energy and macronutrient content

Obesity is a chronic disorder caused by an imbalance of the energy metabolism with high associated burdens. Therefore, huge efforts are being currently devoted in studying new types of hypoenergetic diets and their composition, in order to characterise more specific, long-lasting and safe slimming protocols. A number of investigations are trying to determine the specific influence of the macronutrient distribution in energy-restricted diets on the management of excessive body weight. In this context, very-low-energy diets supplying between 1670 and 3350 kJ (400 and 800 kcal)/d have been beneficial in short-term treatments causing a weight loss of 300-500 g/d. Such strategies place more emphasis on energy restriction than on the macronutrient composition of the diet prescription. Weight loss produced by either low-carbohydrate or low-fat moderately energy-restricted diets ranges from 0.5 to 1.0 kg/week, while diets with high or moderately high protein content have also been applied in weight-reducing programmes by inducing losses of 0.2-0.4 kg/week. Other factors that determine weight loss by dieting are sex, age, initial body weight, race, genetics, regional fat deposition, etc, which must be taken into account to explain the variability in the outcomes of different low-energy diets. Therefore, more research is needed about the impact of diets with different fuel substrates and foods on the characteristics of the weight-loss process.

Safety and feasibility of diet-treated donors with steatotic livers at the initial consultation for living-donor liver transplantation

BACKGROUND

The purpose of this study was to evaluate both safety of diet-treated donors and the feasibility of their use for living-donor liver transplantation (LDLT).

METHODS

A total of 128 living donors were enrolled in this study between April 2003 and March 2010. Of them, 41 were diagnosed with hepatic steatosis at the initial consultation. Donor selection was based on the findings of liver biopsy accompanied with normalization of liver function tests after diet treatment consisting of an 800 to 1400 kcal/day diet and a 100 to 400 kcal/day exercise without drug treatment, targeting body mass index of 22 kg/m².

RESULTS

Body mass index of diet-treated donors was significantly reduced with diet from 23.3 ± 0.6 to 21.9 ± 0.4 kg/m² (P<0.0001). Liver function tests associated with fatty liver, including alanine aminotransferase, gamma-glutamyl transpeptidase, and total cholesterol levels, also improved with diet (P=0.0128, 0.0016, and 0.0004, respectively). The liver biopsy results of most of these donors showed stage 0/1 fibrosis and minimal/mild steatosis after the diet therapy. Surgical outcomes, including postoperative liver function tests, perioperative complications, and liver regeneration rates, did not significantly differ between nondiet-treated and diet-treated donors. Surgical outcomes and the overall survival did not significantly differ between recipients of grafts from nondiet-treated and diet-treated donors.

CONCLUSION

The use of diet-treated donors for living-donor liver transplantation is feasible with respect to donor safety and the outcome of the recipient when strict selection criteria are used.

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

Evidence from the literature supports the safe use of very-low-energy diets (VLED) for up to 3 months in supervised conditions for patients who fail to meet a target weight loss using a standard low-fat, reduced-energy approach. There is, however, a need for longer-term outcomes on obesity and associated morbidities following a VLED. The present systematic review aims to investigate longer-term outcomes from studies using VLED, with a minimum duration of 12 months, published between January 2000 and December 2010. Studies conducted in both children and adults, with a mean/median BMI of ≥ 28 kg/m2 were included. PubMed, MEDLINE, Web of Science and Science Direct were searched. Reference lists of studies and reviews were manually searched. Weight loss or prevention of weight gain and morbidities were the main outcomes assessed. A total of thirty-two out of 894 articles met the inclusion criteria. The duration of the studies ranged from 12 months to 5 years. Periods of VLED ranged from 25 d to 9 months. Several studies incorporated aspects of behaviour therapy, exercise, low-fat diets, low-carbohydrate diets or medication. Current evidence demonstrates significant weight loss and improvements in blood pressure, waist circumference and lipid profile in the longer term following a VLED. Interpretation of the results, however, was restricted and conclusions with which to guide best practice are limited due to heterogeneity between the studies. The present review clearly identifies the need for more evidence and standardised studies to assess the longer-term benefits from weight loss achieved using VLED.

Perioperative optimization of patients undergoing bariatric surgery

Bariatric surgery is fast becoming an efficient and safe method of weight reduction, especially for patients in whom conservative measures have failed. As the obese population of the world increases, so will the number of patients requesting or requiring surgical weight loss methods. Bariatric patients however have numerous co-morbidities that make their operative course more difficult, and therefore is important to have a good understanding of the important issues surrounding their pre, peri and post operative management. This article aims to educate the reader about optimal management of the bariatric surgical patient.

Less fat reduction per unit weight loss in type 2 diabetic compared with nondiabetic obese individuals completing a very-low-calorie diet program

The objective was to compare weight loss and change in body composition in obese subjects with and without type 2 diabetes mellitus during a very-low-calorie diet (VLCD) program. Seventy weight-matched subjects with diabetes or normal fasting glucose (controls) participated in a 24-week VLCD study. Primary end points were changes in anthropometry, body composition, and fasting plasma insulin and β-hydroxybutyrate concentrations. Fifty-one subjects (24 with diabetes) completed the study. No difference in weight loss between the 2 groups at 24 weeks was found by intention-to-treat analysis. Both groups completing the study per protocol had near-identical weight change during the program, with similar weight loss at 24 weeks (diabetes: 8.5 ± 1.3 kg vs control: 9.4 ± 1.2 kg, P = .64). Change in fat mass index correlated with change in body mass index (BMI) in both groups (diabetes: r = 0.878, control: r = 0.920, both P < .001); but change in fat mass index per unit change in BMI was less in the diabetic group compared with controls (0.574 vs 0.905 decrease, P = .003), which persisted after adjusting for age, sex, and baseline BMI (P = .008). Insulin concentrations remained higher and peak β-hydroxybutyrate concentrations were lower in the diabetic compared with the control group. While following a 24-week VLCD program, obese subjects with and without diabetes achieved comparable weight loss; but the decrease in adiposity per unit weight loss was attenuated in diabetic subjects. Hyperinsulinemia may have inhibited lipolysis in the diabetic group; however, further investigation into other factors is needed.

Usefulness of combining intermittent hypoxia and physical exercise in the treatment of obesity

Obesity is an important public health problem worldwide and is a major risk factor for a number of chronic diseases such as type II diabetes, adverse cardiovascular events and metabolic syndrome-related features. Different treatments have been applied to tackle body fat accumulation and its associated clinical manifestations. Often, relevant weight loss is achieved during the first 6 months under different dietary treatments. From this point, a plateau is reached, and a gradual recovery of the lost weight may occur. Therefore, new research approaches are being investigated to assure weight maintenance. Pioneering investigations have reported that oxygen variations in organic systems may produce changes in body composition. Possible applications of intermittent hypoxia to promote health and in various pathophysiological states have been reported. The hypoxic stimulus in addition to diet and exercise can be an interesting approach to lose weight, by inducing higher basal noradrenalin levels and other metabolic changes whose mechanisms are still unclear. Indeed, hypoxic situations increase the diameter of arterioles, produce peripheral vasodilatation and decrease arterial blood pressure. Furthermore, hypoxic training increases the activity of glycolytic enzymes, enhancing the number of mitochondria and glucose transporter GLUT-4 levels as well as improving insulin sensitivity. Moreover, hypoxia increases blood serotonin and decreases leptin levels while appetite is suppressed. These observations allow consideration of the hypothesis that intermittent hypoxia induces fat loss and may ameliorate cardiovascular health, which might be of interest for the treatment of obesity. This new strategy may be useful and practical for clinical applications in obese patients.

Very low calorie diet (VLCD) followed by a randomized trial of corset treatment for obesity in primary care

OBJECTIVE

The primary objective was to investigate the feasibility and cost-effectiveness of weight reduction using very low calorie diet (VLCD) in groups. The secondary objective was to investigate whether subsequent corset treatment could maintain the weight reduction long term.

DESIGN

Participants, consecutively included in groups of 8-14 subjects, underwent three months of VLCD with lifestyle advice at group meetings. Subjects attaining > or = 8 kg reduction were randomized to corset (A) or no corset (B) treatment for nine months. Weight was registered at all meetings and after 24 months. Costs were calculated using current salaries and anti-obesity drug prices as at 2008.

SETTINGS

Primary care in Skaraborg, Sweden. Subjects. A total of 26 men and 65 women aged 30-60 years with BMI > or = 30-< 45 kg/m2.

MAIN OUTCOME MEASURES

Weight changes and costs of treatment.

RESULTS

VLCD (dropout n = 14) resulted in a mean weight reduction of 20.1+/-6.6 kg (20 men) and 15.7+/-4.7 kg (57 women). These 77 subjects were randomized to treatment A (n = 39) or B (n = 38). Compliance with corset was only 20% after three months. After one year (dropout n = 17) weight loss was 11.7+/-8.1 kg (A) and 9.3+/-6.9 kg (B), p = 0.23 and after two years (dropout n = 22) 6.1+/-7.0 kg and 4.4+/-7.3 kg respectively, p = 0.94. Serum glucose and lipids were altered favourably. The cost per participant of treatments A and B was SEK 4440 and SEK 1940 respectively.

CONCLUSIONS

VLCD in groups was feasible and reduced weight even after one year. The cost of treatment was lower than drug treatment. Corset treatment suffered from poor compliance and could therefore not be evaluated.

One-year weight maintenance after significant weight loss in healthy overweight and obese subjects: does diet composition matter?

BACKGROUND

For many people, maintenance of weight loss is elusive. Whereas high-protein (HP) diets have been found to be superior to high-carbohydrate (HC) diets for weight loss in the short term, their benefits long term are unclear, particularly for weight maintenance. Furthermore, the literature lacks consensus on the long-term effects of an HP diet on cardiovascular disease risk factors.

OBJECTIVE

The objective was to investigate whether macronutrient dietary composition plays a role in weight maintenance and in improvement of cardiovascular disease risk factors.

DESIGN

The study comprised 2 phases. Phase 1 featured a very-low-energy diet for 3 mo. In phase 2, the subjects were randomly assigned to an HP or an HC diet for 12 mo. The diets were isocaloric, tightly controlled, and individually prescribed for weight maintenance. The subjects were overweight or obese but otherwise healthy men and women.

RESULTS

The subjects lost an average of 16.5 kg during phase 1 and maintained a mean (+/-SEM) weight loss of 14.5 +/- 1.2 kg (P < 0.001) during phase 2; no significant differences between groups were observed. By the end of the study, reductions in systolic blood pressure were 14.3 +/- 2.4 mm Hg for the HP group and 7.7 +/- 2.2 mm Hg for the HC group (P < 0.045). Forty-seven percent of the 180 subjects who began the study completed both phases.

CONCLUSIONS

The results indicate that the protein or carbohydrate content of the diet has no effect on successful weight-loss maintenance. A general linear model analysis indicated that dietary treatment (HP or HC) was a significant factor in systolic blood pressure change and in favor of the HP diet. This trial was registered at www.clinicaltrials.gov as NCT 00625236.

Effects and clinical potential of very-low-calorie diets (VLCDs) in type 2 diabetes

A recent study has shown that obese patients with newly diagnosed type 2 diabetes who lose 10% of their body weight are more likely to achieve glycaemic and blood pressure targets, despite weight regain. A well-established non-surgical method for achieving weight loss >or=10% within 3 months is the use of very-low-calorie diets (VLCDs). In patients with diabetes, VLCDs are associated with rapid improvement in glycaemia and cardiovascular risk factors. The present review analyses the evidence from available trials on the effects of VLCDs on body weight, glycaemic control and complications, and their potential for clinical use in diabetes management.

Efficacy and safety of very-low-calorie diet in Taiwanese: a multicenter randomized, controlled trial

OBJECTIVE

Very-low-calorie diets (VLCDs) are an effective method for weight reduction in Caucasians. This study investigated the efficacy and safety of two different VLCDs (450 or 800kcal/d) in obese Taiwanese.

METHODS

132 participants with BMI > or =30kg/m(2) were randomized to two VLCD groups for body weight reduction for 12 weeks. Each group had 66 participants. Anthropometric and metabolic parameters were measured.

RESULTS

The intention-to-treat analysis revealed that the percentage change in body weight over the 12-week treatment period was -9.14% in the VLCD-450 group and -8.98% in the VLCD-800 group. A total of 27 (40.9%) participants in the VLCD-450 group and 29 (43.9%) participants in the VLCD-800 group achieved 10% or more weight loss at the end of treatment. The body weight, waist circumference, hip circumference, fat mass, blood pressure, triglycerides, and blood glucose were statistically improved from baseline but not between the two groups. The improvement rate of nonalcoholic fatty liver disease (NAFLD) was 41.5% in the VLCD-450 group and 50.0% in the VLCD-800 group. The incidence of adverse events did not differ significantly between the groups and no serious adverse events were reported in either group.

CONCLUSION

Both the VLCD-450 and 800kcal/d can effectively and safely reduce body weight and improve NAFLD in 12 weeks in obese Taiwanese participants. However, there is no additional benefit in prescribing the more restrictive diet intervention in Taiwanese.

The effect of a high-MUFA, low-glycaemic index diet and a low-fat diet on appetite and glucose metabolism during a 6-month weight maintenance period

We aimed to test the effects of three different weight maintenance diets on appetite, glucose and fat metabolism following an initial low-energy diet (LED) induced body weight loss. Following an 8-week LED and a 2-3-week refeeding period, 131 subjects were randomized to three diets for 6 months: MUFA, moderate-fat (35-45 energy percentage (E%) fat), high in MUFA with low glycaemic index; LF, low fat (20-30 E% fat) or CTR, control (35 E% fat). A meal test study was performed in a subgroup, before and after the 6-month dietary intervention, with forty-two subjects completing both meal tests. No difference in body weight, energy intake or appetite ratings were observed between diets. Both the LF and MUFA diets compared to CTR diet reduced postprandial glycaemia and insulinaemia and lowered fasting insulin from month 0 to month 6. Following the 8-week LED period lower levels of the appetite regulating peptides, pancreatic polypeptide, peptide YY, glucagon-like peptide-1 and glucagon-like peptide-2, along with increased appetite scores were seen in comparison to measurements performed after the 6-month dietary intervention. In conclusion, the two competing diets, MUFA and LF, were equally good with respect to glucose metabolism, whereas the CTR diet resembling the typical Western diet, high in SFA, sugar and high glycaemic carbohydrates, indicated associations to lowering of insulin sensitivity. Lower levels of appetite regulatory peptides along with increased appetite scores following an 8-week LED and 2-3-week refeeding period, suggest that strategies for physiological appetite control following a LED period are needed, in order to prevent weight regain.