Predictors of weight loss in obese patients with obstructive sleep apnea.

PURPOSE: Consistent predictors of weight loss outcomes with very low-energy diets (VLEDs) in obstructive sleep apnea (OSA) have not been identified. This study aimed to identify variables predictive of weight loss success in obese patients with OSA undertaking an intensive weight loss programme. METHODS: We analysed biological, psychological, and behavioural variables as potential predictors of weight loss in obese patients with OSA after a 2-month VLED followed by one of two 10-month weight loss maintenance diets. Actigraphy, in-lab polysomnography, urinary catecholamines, and various psychological and behavioural variables were measured at baseline, 2, and 12 months. Spearman's correlations analysed baseline variables with 2-month weight loss, and 2-month variables with 2-12 month-weight change. RESULTS: Forty-two patients completed the VLED and thirty-eight completed the maintenance diets. Actigraphy data revealed that late bedtime (rs = - 0.45, p = < 0.01) was correlated with 2-month weight loss. The change in the time that participants got out of bed (rise-time) from baseline to two months was also correlated with 2-month weight loss (rs = 0.36, p = 0.03). The Impact of Weight on Quality of Life-Lite questionnaire (IWQOL) Public Distress domain (rs = - 0.54, p = < 0.01) and total (rs = - 0.38, p = 0.02) scores were correlated with weight loss maintenance from 2 to 12 months. CONCLUSIONS: Results from this small patient sample reveal correlations between actigraphy characteristics and weight loss in obese patients with OSA. We suggest the IWQOL may also be a useful clinical tool to identify OSA patients at risk of weight regain after initial weight loss. CLINICAL TRIAL REGISTRATION: This clinical trial was prospectively registered on 18/02/2013 with the Australia and New Zealand Clinical Trials Registry (ACTRN12613000191796). PUBLIC REGISTRY TITLE: Sleep, Lifestyle, Energy, Eating, Exercise Program for the management of sleep apnea patients indicated for weight loss treatment: A randomised, controlled pilot study. URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=363680.

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.

Comparing the effectiveness of general dietary advice versus a very low energy diet in an obese outpatient population in Australia.

PURPOSE: Obesity is a major public health burden. Outpatient clinics are an essential resource for individuals with obesity to access advice for weight loss management. The aim of this study was to compare anthropometric and weight loss outcomes between participants receiving general dietary (GD) advice, and those on a very low energy diet (VLED) under non-trial conditions. METHODS: Data from 276 adults with obesity attending a multidisciplinary weight management clinic were analysed. Changes in anthropometry, body composition, and blood pressure (BP) over 12 months were analysed using linear mixed-effects models. RESULTS: Males on the GD demonstrated statistically greater reductions in body weight (BW), BMI, percent fat mass (FM), systolic BP, waist and hip circumference (p < 0.01). Changes in males on a VLED did not reach significance. Females showed statistically significant reductions in BW, BMI, waist and hip circumference regardless of dietary intervention (p < 0.01); those on the GD significantly reduced percent FM (p < 0.001). Females on a VLED had statistically greater reductions in BW, BMI and systolic BP compared to those on the GD. No effect of exercise physiologist was observed in this study. Participants prescribed a GD attended for significantly longer than those on a VLED (p < 0.05), irrespective of gender. At 12 months, 14.3 and 4.5% of males and females on a VLED were still attending, compared to 10.6 and 4.5% on the GD. CONCLUSIONS: In this retrospective study, females in both dietary intervention groups achieved significant changes across multiple measures. Only men receiving GD advice demonstrated significant changes. LEVEL OF EVIDENCE: Level II-2.

Timeline of changes in adaptive physiological responses, at the level of energy expenditure, with progressive weight loss.

Diet-induced weight loss (WL) is associated with reduced resting and non-resting energy expenditure (EE), driven not only by changes in body composition but also potentially by adaptive thermogenesis (AT). When exactly this happens, during progressive WL, remains unknown. The aim of this study was to determine the timeline of changes in RMR and exercise-induced EE (EIEE), stemming from changes in body composition v. the presence of AT, during WL with a very-low-energy diet (VLED). In all, thirty-one adults (eighteen men) with obesity (BMI: 37 (sem 4·5) kg/m2; age: 43 (sem 10) years) underwent 8 weeks of a VLED, followed by 4 weeks of weight maintenance. Body weight and composition, RMR, net EIEE (10, 25 and 50 W) and AT (for RMR (ATRMR) and EIEE (ATEIEE)) were measured at baseline, day 3 (2 (sem 1) % WL), after 5 and 10 % WL and at weeks 9 (16 (sem 2) %) and 13 (16 (sem 1) %). RMR and fat mass were significantly reduced for the first time at 5 % WL (12 (sem 8) d) (P<0·01 and P<0·001, respectively) and EIEE at 10 % WL (32 (sem 8) d), for all levels of power (P<0·05), and sustained up to week 13. ATRMR was transiently present at 10 % WL (-460 (sem 690) kJ/d, P<0·01). A fall in RMR should be anticipated at ≥5 % WL and a reduction in EIEE at ≥10 % WL. Transient ATRMR can be expected at 10 % WL. These physiological adaptations may make progressive WL difficult and will probably contribute to relapse.

Reversal of type 2 diabetes in youth who adhere to a very-low-energy diet: a pilot study.

AIMS/HYPOTHESIS: The aim of the study was to investigate whether a very-low-energy diet (VLED) is a feasible and acceptable treatment option for type 2 diabetes in children and adolescents, and whether adherence can lead to rapid weight loss, reversal of type 2 diabetes and reduced liver fat as seen in adult studies. METHODS: Eight participants with type 2 diabetes and obesity, aged 7-16 years, non-medicated (n = 1) or treated with metformin (n = 7) and in some cases insulin (n = 3), followed a VLED (<3360 kJ/day) for 8 weeks, then transitioned to a hypocaloric diet (∼6300 kJ/day) that they followed to 34 weeks. HbA1c, fasting glucose and 2 h post-glucose load plasma glucose (2hG) were determined from fasting blood and an OGTT. Liver fat concentration was quantified using proton magnetic resonance spectroscopy. Adherence was defined as ≥5% weight loss during the 8 week VLED. RESULTS: Adherers (n = 5) and non-adherers (n = 3) had median weight loss of 7.5% and 0.5%, respectively, at 8 weeks. Overall, HbA1c (mean [SE] 8.1% [0.7%] to 6.6% [0.5%]; p = 0.004) and 2hG (15.6 [1.6] mmol/l to 11.3 [1.0] mmol/l; p = 0.009) were significantly reduced at 8 weeks compared with baseline. Liver fat was also significantly reduced from baseline (14.7% [2.2%]) to 8 weeks (5.8% [1.7%]; p = 0.001). Only three out of eight participants met non-alcoholic fatty liver disease (NAFLD) criteria (≥5.5%) at 8 weeks, compared with eight out of eight at baseline. The three participants on insulin therapy at baseline were able to cease therapy during the 8 week VLED. At 34 weeks, adherers (n = 5) achieved 12.3% weight loss, none met NAFLD criteria and four did not meet American Diabetes Association criteria for type 2 diabetes. CONCLUSIONS/INTERPRETATION: A VLED appears to be a feasible treatment option for some youth with type 2 diabetes on metformin therapy. Youth who agree to participate and adhere to a VLED achieve rapid weight loss, dramatic reductions in liver fat and reversal of type 2 diabetes. This highlights the capacity of a VLED to be used as a first-line treatment option in newly diagnosed youth. A larger trial with a control group and longer follow-up will be required to encourage a change in standard treatment. TRIAL REGISTRATION: Australian New Zealand Clinical Trial Registration Number (ACTRN) ACTRN12616000375459 ( www.ANZCTR.org.au/ACTRN12616000375459.aspx ).

Morphology of the pancreas in type 2 diabetes: effect of weight loss with or without normalisation of insulin secretory capacity.

AIMS/HYPOTHESIS: This study was designed to establish whether the low volume and irregular border of the pancreas in type 2 diabetes would be normalised after reversal of diabetes. METHODS: A total of 29 individuals with type 2 diabetes undertook a very low energy (very low calorie) diet for 8 weeks followed by weight maintenance for 6 months. Methods were established to quantify the pancreas volume and degree of irregularity of the pancreas border. Three-dimensional volume-rendering and fractal dimension (FD) analysis of the MRI-acquired images were employed, as was three-point Dixon imaging to quantify the fat content. RESULTS: There was no change in pancreas volume 6 months after reversal of diabetes compared with baseline (52.0 ± 4.9 cm(3) and 51.4 ± 4.5 cm(3), respectively; p = 0.69), nor was any volumetric change observed in the non-responders. There was an inverse relationship between the volume and fat content of the pancreas in the total study population (r =-0.50, p = 0.006). Reversal of diabetes was associated with an increase in irregularity of the pancreas borders between baseline and 8 weeks (FD 1.143 ± 0.013 and 1.169 ± 0.006, respectively; p = 0.05), followed by a decrease at 6 months (1.130 ± 0.012, p = 0.006). On the other hand, no changes in FD were seen in the non-reversed group. CONCLUSIONS/INTERPRETATION: Restoration of normal insulin secretion did not increase the subnormal pancreas volume over 6 months in the study population. A significant change in irregularity of the pancreas borders occurred after acute weight loss only after reversal of diabetes. Pancreas morphology in type 2 diabetes may be prognostically important, and its relationship to change in beta cell function requires further study.

Comparison of the Nutritional Adequacy of Current Food-Based Very Low Energy Diets: A Review and Nutritional Analysis.

Very low energy diets (VLEDs) contain <800 kcal/day and typically comprise formulated meal replacement products with adequate protein and micronutrients. Food-based VLEDs are an alternative approach, but it is uncertain whether they can provide adequate nutrition within an 800 kcal/day restriction. This analysis aimed to assess the nutritional adequacy of food-based VLEDs compared with formula VLEDs. A systematized literature review was conducted to identify balanced food-based VLEDs by searching five scientific databases from inception to 23 March 2023 and online sources between 1 and 7 May 2023. Ultimately, nine diets were analyzed for nutritional content and compared with Codex Alimentarius standards for formula foods, and Australian estimated average requirement and adequate intake (AI) for adults 19-50 years. Optifast® was used as a comparator. None of the VLEDs met all nutritional benchmarks. Three food-based diets had nutrient profiles similar to formula VLEDs, with one being adequate for all nutrients except thiamine, magnesium and zinc in men and iron in women. All VLEDs, including Optifast®, did not meet AI for dietary fiber, except one. In general, food-based VLEDs offered more fiber than Optifast®. In conclusion, food-based VLEDs were inadequate in certain micronutrients but offered more dietary fiber than formula VLEDs. These nutritional deficits do not preclude food-based VLEDs from being recommended, provided they are addressed.

Efficacy, Safety and Acceptability of a Very-Low-Energy Diet in Adolescents with Obesity: A Fast Track to Health Sub-Study.

The aim of this study was to determine the efficacy, safety and acceptability of a 4-week very-low-energy diet (VLED) program for adolescents with obesity. Adolescents (13-17 years) with obesity and ≥1 obesity-related complication were Fast Track to Health 52-week randomized controlled trial participants. Adolescents undertook a 4-week micronutrient-complete VLED (800 kcal/day), with weekly dietitian support. Anthropometric data were recorded at baseline and week-4 and side-effects at day 3-4, week-1, -2, -3 and -4. Adolescents completed an acceptability survey at week-4. A total of 134 adolescents (14.9 ± 1.2 years, 50% male) had a 5.5 ± 2.9 kg (p < 0.001) mean weight loss at week-4: 95% experienced ≥1 and 70% experienced ≥3 side-effects during the VLED program, especially during the first week. Hunger, fatigue, headache, irritability, loose stools, constipation and nausea were most common. Reporting more side-effects at day 3-4 correlated with greater weight loss at week-4 (r = -0.188, p = 0.03). Adolescents reported 'losing weight' (34%) and 'prescriptive structure' (28%) as the most positive aspects of VLED, while 'restrictive nature' (45%) and 'meal replacement taste' (20%) were least liked. A dietitian-monitored short-term VLED can be implemented safely and is acceptable for many adolescents seeking weight loss, despite frequent side-effects. Investigating predictors of acceptability and effectiveness could determine adolescents most suited to VLED programs.

Variation and outcomes of liver-reducing dietary regimens before bariatric surgery: a national retrospective cohort study.

BACKGROUND: Liver-reducing diets (LRDs) are mandated prior to bariatric surgery, but there are no guidelines on their implementation. OBJECTIVE: To establish the variation and effectiveness of LRDs utilized in clinical practice. SETTING: A nationwide, multicenter, retrospective cohort study. METHODS: A total of 1699 adult patients across 14 bariatric centers in the United Kingdom were included. Multilevel logistic regression models were developed to examine factors predictive of 5% weight loss. RESULTS: Most centers (n = 9) prescribed an 800- to 1000-kcal diet, but the duration and formulation of diet was variable. Overall, 30.6% (n = 510) of patients achieved 5% weight loss during the LRD. After adjustment for preoperative weight, women had reduced odds (odds ratio [OR], .65; 95% confidence interval [CI], .48-.88; P = .005), while increasing age (OR, 1.01; 95% CI, 1.00-1.02; P = .043) and having type 2 diabetes (OR, 1.49; 95% CI, 1.16-1.92; P = .002) increased odds of 5% weight loss. A normal consistency food LRD (OR, .64; 95% CI, .42-.98; P = .041) and energy prescription of >1200 kcals/d (OR, .33; 95% CI, .13-.83; P = .019) reduced odds, while an LRD with a duration of 3 weeks (OR, 2.28; 95% CI, 1.02-5.09; P = .044) or greater increased odds of 5% weight loss. CONCLUSIONS: There is wide variation in how LRDs are delivered in clinical practice, highlighting the need for an evidence-based consensus. Our findings suggest the optimal LRD before bariatric surgery contains 800 to 1200 kcals/d over a duration of 3 to 4 weeks. Further research is required to determine the optimal formulation of LRD and whether women may require a lower-energy LRD than men.

Predictors of weight loss in patients with obesity treated with a Very Low-Calorie Ketogenic Diet.

Introduction: The Very Low-Calorie Ketogenic Diet (VLCKD) has emerged as a safe and effective intervention for the management of metabolic disease. Studies examining weight loss predictors are scarce and none has investigated such factors upon VLCKD treatment. Among the molecules involved in energy homeostasis and, more specifically, in metabolic changes induced by ketogenic diets, Fibroblast Growth Factor 21 (FGF21) is a hepatokine with physiology that is still unclear. Methods: We evaluated the impact of a VLCKD on weight loss and metabolic parameters and assessed weight loss predictors, including FGF21. VLCKD is a severely restricted diet (<800 Kcal/die), characterized by a very low carbohydrate intake (<50 g/day), 1.2-1.5 g protein/kg of ideal body weight and 15-30 g of fat/day. We treated 34 patients with obesity with a VLCKD for 45 days. Anthropometric parameters, body composition, and blood and urine chemistry were measured before and after treatment. Results: We found a significant improvement in body weight and composition and most metabolic parameters. Circulating FGF21 decreased significantly after the VLCKD [194.0 (137.6-284.6) to 167.8 (90.9-281.5) p < 0.001] and greater weight loss was predicted by lower baseline FGF21 (Beta = -0.410; p = 0.012), male sex (Beta = 0.472; p = 0.011), and central obesity (Beta = 0.481; p = 0.005). Discussion: VLCKD is a safe and effective treatment for obesity and obesity related metabolic derangements. Men with central obesity and lower circulating FGF21 may benefit more than others in terms of weight loss obtained following this diet. Further studies investigating whether this is specific to this diet or to any caloric restriction are warranted.

Very low energy diets prior to bariatric surgery may reduce postoperative morbidity: a systematic review and meta-analysis of randomized controlled trials.

Purpose: To optimize patients prior to bariatric surgery, very low energy diets (VLEDs) are often employed for 2-4 weeks preoperatively. They are known to result in preoperative weight loss, decrease liver volume, and decrease surgeon-perceived operative difficulty. Their impact on postoperative morbidity has been less extensively studied. We performed a focused systematic review and meta-analysis with the aim of comparing preoperative VLEDs prior to bariatric surgery with controls in terms of overall postoperative morbidity. Methods: MEDLINE, Embase, and CENTRAL were searched from database inception to February 2023. Articles were eligible for inclusion if they were randomized controlled trials (RCTs) comparing postoperative morbidity in adult patients (i.e., over the age of 18) receiving a VLED with liquid formulation to those receiving a non-VLED control prior to elective bariatric surgery. Outcomes included overall 30-day postoperative morbidity and preoperative weight loss. An inverse variance meta-analysis was performed with GRADE assessment of the quality of evidence. Results: After reviewing 2,525 citations, four RCTs with 294 patients receiving preoperative VLEDs with liquid formulation and 294 patients receiving a non-VLED control met inclusion. Patients receiving VLED experienced significantly more preoperative weight loss than patients receiving control (mean difference (MD) 3.38 kg, 95% confidence interval (CI) 1.06-5.70, p = 0.004, I2 = 95%). According to low certainty evidence, there was a non-significant reduction in 30-day postoperative morbidity in patients receiving VLED prior to bariatric surgery (risk ratio (RR) 0.67, 95%CI 0.39-1.17, p = 0.16, I2 = 0%). Conclusion: The impact of preoperative VLEDs on postoperative outcomes following bariatric surgery remains unclear. It is possible that VLEDs may contribute to decreased postoperative morbidity, but further larger prospective trials are required to investigate the signal identified in this study.

The (cost) effectiveness of a very low-energy diet intervention with the use of eHealth in patients with type 2 diabetes and obesity: study protocol for a randomised controlled non-inferiority trial (E-diet trial).

BACKGROUND: Despite preventive measures, the number of people with type 2 diabetes and obesity is increasing. Obesity increases morbidity and mortality in people with type 2 diabetes, making weight loss a cornerstone of treatment. We previously developed a very low energy diet (VLED) intervention that effectively reduced weight in people with type 2 diabetes in the long term. However, this intervention requires considerable time and manpower, which reduces the number of people who can benefit from it. eHealth offers more efficient solutions but has proven to be less effective than face-to-face interventions. Therefore, we want to investigate whether a blended version of our VLED intervention (in which face-to-face contact is partly replaced by an eHealth (mobile) application (E-VLED)) would be more cost-effective than the current face-to-face intervention. METHODS: We will conduct a randomised, controlled trial with non-inferiority design in patients with type 2 diabetes and obesity (BMI > 30 kg/m2), aged 18-75 years. The control group will receive the usual care VLED intervention, while the intervention group will receive the E-VLED intervention for 1 year, where face-to-face contact will be partly replaced by an eHealth (mobile) application. The main study endpoint is the difference in weight (% change) between the control and intervention group after 1 year, plus the difference between the total costs (euro) of the treatment in the control and intervention groups. The secondary aims are to investigate the effectiveness of the E-VLED diet intervention regarding cardiovascular risk factors, quality of life, patient satisfaction, compliance, and to study whether there is a difference in effectiveness in pre-specified subgroups. General linear models for repeated measurements will be applied for the statistical analysis of the data. DISCUSSION: We hypothesise that the E-VLED intervention will be equally effective compared to the usual care VLED but lower in costs due to less time invested by the dietician. This will enable to help more people with type 2 diabetes and obesity to effectively lose weight and improve their health-related quality of life. TRIAL REGISTRATION: Netherlands Trial Register, NL7832, registered on 26 June 2019.

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.

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.

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.

The Australian Obesity Management Algorithm: A simple tool to guide the management of obesity in primary care.

Obesity is a complex and multifactorial chronic disease with genetic, environmental, physiological and behavioural determinants that requires long-term care. Obesity is associated with a broad range of complications including type 2 diabetes, cardiovascular disease, dyslipidaemia, metabolic associated fatty liver disease, reproductive hormonal abnormalities, sleep apnoea, depression, osteoarthritis and certain cancers. An algorithm has been developed (with PubMed and Medline searched for all relevant articles from 1 Jan 2000-1 Oct 2021) to (i) assist primary care physicians in treatment decisions for non-pregnant adults with obesity, and (ii) provide a practical clinical tool to guide the implementation of existing guidelines (summarised in Appendix 1) for the treatment of obesity in the Australian primary care setting. MAIN RECOMMENDATIONS AND CHANGES IN MANAGEMENT: Treatment pathways should be determined by a person's anthropometry (body mass index (BMI) and waist circumference (WC)) and the presence and severity of obesity-related complications. A target of 10-15% weight loss is recommended for people with BMI 30-40 kg/m2 or abdominal obesity (WC > 88 cm in females, WC > 102 cm in males) without complications. The treatment focus should be supervised lifestyle interventions that may include a reduced or low energy diet, very low energy diet (VLED) or pharmacotherapy. For people with BMI 30-40 kg/m2 or abdominal obesity and complications, or those with BMI > 40 kg/m2 a weight loss target of 10-15% body weight is recommended, and management should include intensive interventions such as VLED, pharmacotherapy or bariatric surgery, which may be required in combination. A weight loss target of > 15% is recommended for those with BMI > 40 kg/m2 and complications and they should be referred to specialist care. Their treatment should include a VLED with or without pharmacotherapy and bariatric surgery.

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.

Novel dietary interventions for adolescents with obesity: A narrative review.

Adolescent obesity is increasing and a range of treatment approaches are needed. Provision of tailored treatment options accounting for individual and family needs, preferences, and capacity may encourage adolescents with obesity to seek treatment, and/or improve treatment outcomes. Delivered by trained health care professionals, novel dietary interventions may have utility for adolescents not responding to conventional diets, adolescents with comorbidities or severe obesity, and/or when rapid or substantial weight loss is required. This review describes current evidence and clinical considerations relating to the use of very low energy diets, low carbohydrate diets, and intermittent energy restriction in the treatment of adolescent obesity. Emerging evidence on the use of these novel dietary interventions demonstrates short-term weight-related and cardiometabolic improvements. While the evidence is encouraging, and no serious adverse effects have been reported, monitoring of intervention safety is essential. Considerations for health care professionals providing care to adolescents include nutritional adequacy, psychosocial health and social relationships during the intervention. Furthermore, long-term weight-related, cardiometabolic and psychological health outcomes of these dietary interventions are not well understood. Large randomised controlled trials are warranted to inform clinical practice and future guidelines for the use of novel dietary interventions in adolescents with obesity.

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 (ß-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 ß-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 ß-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 ß-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.

Time to pregnancy after a prepregnancy very-low-energy diet program in women with obesity: substudy of a randomized controlled trial.

OBJECTIVE: To examine the impact of a prepregnancy very-low-energy diet (VLED) program on time to pregnancy in women with obesity. DESIGN: Substudy of a two-arm parallel group randomized controlled trial. SETTING: Multiple tertiary care centers. PATIENT(S): Women 18-38 years old with obesity (body mass index 30-55 kg/m2) and planning conception. INTERVENTION(S): One hundred sixty-four normoglycemic women with body mass index 30-55 kg/m2, aged 18-38 years, and planning pregnancy were recruited through a social media platform for a two-arm randomized controlled trial. Women were allocated to a 12-week standard dietary intervention (SDI) or modified VLED. Completers of the intervention were observed for up to 48 weeks, and time to pregnancy was recorded. MAIN OUTCOME MEASURE(S): The prespecified exploratory outcome for this substudy was time to pregnancy between the completion of the 12-week intervention and the date of conception. RESULT(S): Maternal weight loss at the end of the 12-week intervention was 3.1% in the SDI group and 11.9% in the VLED group. In completers of the 12-week intervention, time to pregnancy was significantly shorter in the women allocated to the VLED group than in the SDI group. Post hoc analysis showed that this difference in time to conception was particularly overt within 90 days of the intervention. CONCLUSION(S): A VLED program that achieves substantial weight loss before conception reduces time to pregnancy compared with an SDI in women with obesity. TRIAL REGISTRATION NUMBER: ACTRN12614001160628.