Low-calorie Diet Research Articles

BENEFICIAL ROLE OF DIETARY CHANGES IN MENOPAUSE: IMPACT ON CARDIOVASCULAR RISK

Objective: The changing hormonal milieu in post-menopausal women (PMW) predisposes them to increase cardiovascular (CV) risk, due to a constellation of risk factors, such as visceral obesity, atherogenic dyslipidemia and arterial hypertension. Our ongoing study aims to evaluate the impact of dietary changes in CV risk in PMW. Design and method: For 1 year, 65 PMW with BMI 24-39 Kg/m2 and at least another CV risk factor were followed. Anthropometric parameters, plicometry and blood pressure (BP) were taken. Questionnaires on medical history, physical activity, and food frequency (FFQ) were administered. Balanced low-calorie dietary plan with quantitative advice were released. Repeated measures ANOVA at 1 year were performed. Results: We observed at 1 year significant reductions (p<0.01) in weight (δ=-4.5 Kg), BMI (δ=-1.7 Kg/m2), waist (δ=-4.3cm) and hips (δ=-3.1cm) circumferences, subscapular (δ=-5.8mm), suprailiac (δ=-3.3mm) and triceps (δ=-5.5mm) skinfolds, adipose area of the arm (AFA) (δ=-7.3cm2), and fat mass (δ=-4.5kg) without variation of the lean mass (δ=-0.1 kg, p=0.48). All those reductions were followed by change in the obesity prevalence (-21.1%), in the fat mass distribution with 10% reduction in abdominal and truncular obesity and 5.2% reduction on waist-to-height ratio, and in systolic (δ=-8.8 mmHg) and diastolic (δ=-4.3 mmHg) BP. Significant positive correlations (p<0.0001) were observed between weight reduction and the following variables: waist (r=0.61) and hip (r=0.77) circumferences, subscapularis (r=0.56) and triceps (r=0.66) skinfolds, and AFA (r=0.73). Significant reductions (p<0.05) were observed in daily caloric intake (δ=-99.8Kcal/day), due to the reduction in fat intake (36.6->33.6%), specially saturated fatty acids (12->10.8%) and cholesterol (δ=-23.1mg/day), with maintenance of the average level of physical activity and in agreement with a significant reductions in consumption of animal meats, visible fat, processed meats, olive oil, sweets and baked goods detected by FFQ. Conclusions: The study underlines the medium-term utility of a 1 year balanced low-calorie diet in PMW with elevated CV risk factors with a clear reduction in CV risk.

Incretin-Based Weight Loss Pharmacotherapy: Can Resistance Exercise Optimize Changes in Body Composition?

This narrative review highlights the degree to which new antiobesity medications based on gut-derived nutrient-stimulated hormones (incretins) cause loss of lean mass, and the importance of resistance exercise to preserve muscle. Glucagon-like peptide 1 receptor agonists (GLP-1RA) induce substantial weight loss in randomized trials, effects that may be enhanced in combination with glucose-dependent insulinotropic polypeptide (GIP) receptor agonists. Liraglutide and semaglutide (GLP-1RA), tirzepatide (GLP-1 and GIP receptor dual agonist), and retatrutide (GLP-1, GIP, and glucagon receptor triple agonist) are peptides with incretin agonist activity that induce ∼15-24% weight loss in adults with overweight and obesity, alongside beneficial impacts on blood pressure, cholesterol, blood glucose, and insulin. However, these agents also cause rapid and significant loss of lean mass (∼10% or ∼6 kg), comparable to a decade or more of aging. Maintaining muscle mass and function as humans age is crucial to avoiding sarcopenia and frailty, which are strongly linked to morbidity and mortality. Studies indicate that supervised resistance exercise training interventions with a duration >10 weeks can elicit large increases in lean mass (∼3 kg) and strength (∼25%) in men and women. After a low-calorie diet, combining aerobic exercise with liraglutide improved weight loss maintenance compared with either alone. Retaining lean mass during incretin therapy could blunt body weight (and fat) regain on cessation of weight loss pharmacotherapy. We propose that tailored resistance exercise training be recommended as an adjunct to incretin therapy to optimize changes in body composition by preserving lean mass while achieving fat loss.

Short-term effects of obesity surgery versus low-energy diet on body composition and tissue-specific glucose uptake: a randomised clinical study using whole-body integrated 18F-FDG-PET/MRI

Aims/hypothesisObesity surgery (OS) and diet-induced weight loss rapidly improve insulin resistance. We aim to investigate the impact of either Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) surgery compared with a diet low in energy (low-calorie diet; LCD) on body composition, glucose control and insulin sensitivity, assessed both at the global and tissue-specific level in individuals with obesity but not diabetes.MethodsIn this parallel group randomised controlled trial, patients on a waiting list for OS were randomised (no blinding, sealed envelopes) to either undergo surgery directly or undergo an LCD before surgery. At baseline and 4 weeks after surgery (n=15, 11 RYGB and 4 SG) or 4 weeks after the start of LCD (n=9), investigations were carried out, including an OGTT and hyperinsulinaemic–euglycaemic clamps during which concomitant simultaneous whole-body [18F]fluorodeoxyglucose-positron emission tomography (PET)/MRI was performed. The primary outcome was HOMA-IR change.ResultsOne month after bariatric surgery and initiation of LCD, both treatments induced similar reductions in body weight (mean ± SD: −7.7±1.4 kg and −7.4±2.2 kg, respectively), adipose tissue volume (7%) and liver fat content (2% units). HOMA-IR, a main endpoint, was significantly reduced following OS (−26.3% [95% CI −49.5, −3.0], p=0.009) and non-significantly following LCD (−20.9% [95% CI −58.2, 16.5). For both groups, there were similar reductions in triglycerides and LDL-cholesterol. Fasting plasma glucose and insulin were also significantly reduced only following OS. There was an increase in glucose AUC in response to an OGTT in the OS group (by 20%) but not in the LCD group. During hyperinsulinaemia, only the OS group showed a significantly increased PET-derived glucose uptake rate in skeletal muscle but a reduced uptake in the heart and abdominal adipose tissue. Both liver and brain glucose uptake rates were unchanged after surgery or LCD. Whole-body glucose disposal and endogenous glucose production were not significantly affected.Conclusions/interpretationThe short-term metabolic effects seen 4 weeks after OS are not explained by loss of body fat alone. Thus OS, but not LCD, led to reductions in fasting plasma glucose and insulin resistance as well as to distinct changes in insulin-stimulated glucose fluxes to different tissues. Such effects may contribute to the prevention or reversal of type 2 diabetes following OS. Moreover, the full effects on whole-body insulin resistance and plasma glucose require a longer time than 4 weeks.Trial registrationClinicalTrials.gov NCT02988011FundingThis work was supported by AstraZeneca R&D, the Swedish Diabetes Foundation, the European Union’s Horizon Europe Research project PAS GRAS, the European Commission via the Marie Sklodowska Curie Innovative Training Network TREATMENT, EXODIAB, the Family Ernfors Foundation, the P.O. Zetterling Foundation, Novo Nordisk Foundation, the Agnes and Mac Rudberg Foundation and the Uppsala University Hospital ALF grantsGraphical

Fresh start with high hopes: a qualitative evaluation of experiences of the Total Diet Replacement phase of the NHS Low Calorie Diet Programme pilot

Background: The National Health Service (NHS) Low Calorie Diet (LCD) programme in England aims to support people with type 2 diabetes (T2DM) to lose weight, improve glycaemic parameters and potentially achieve diabetes remission. The programme pilot launched in 2020 using three different delivery models: one-to-one, group and digital via an App. Service users begin the programme with 12 weeks of Total Diet Replacement (TDR). This study aims to understand the experience of this TDR phase from the service user perspective. Methods: This was a co-produced qualitative longitudinal and cross-sectional study, underpinned by a realist informed approach using semi-structured interviews and photovoice techniques. Service users (n=45) from the NHS LCD programme were recruited across the three delivery models and 21 pilot sites in England. Data were analysed using a thematic approach. Results: Participant demographics were representative of the overall LCD pilot population sample and included experiences from a mix of delivery models and providers. Three themes were presented chronologically. 1) life pre-LCD: the LCD programme was viewed as an opportunity to reset eating behaviours and improve quality of life; 2) experience of TDR: flexibility in allowing supplementary non-starchy vegetables and adapting the flavour and texture of TDR products supported adherence; 3) looking ahead to food reintroduction: at the end of the TDR phase, weight and glycaemia had reduced, while subjective energy levels and mobility improved. Some participants were concerned about progressing to the food reintroduction phase and the possibility of weight regain. Conclusions: The paper reports insight from the TDR phase of the LCD programme. The co-production of this work has resulted in several recommendations for policy and practice which have informed the national roll out of the programme.

Qualitative study of the experiences of individuals who did not complete the NHS Low Calorie Diet Programme Pilot

Background: Attrition remains a significant public health challenge as individuals who do not complete programmes are likely to have poorer programme outcomes. On calorie- restricted diets, including the NHS Low Calorie Diet (LCD) Programme pilot, approximately 50% of people are discharged prematurely, and thus do not complete the programme. Reducing attrition therefore has the potential to improve programme efficacy, impact and cost-effectiveness. Methods: Ten semi-structured interviews were conducted with purposively sampled individuals who did not complete the NHS LCD programme. Interviews explored service user experiences of the programme and experiences of being discharged. Interview data were analysed thematically. Results: Four core themes were identified: 1) the pre- programme struggles of service users and their route to LCD; 2) a positive and impactful programme; 3) life gets in the way; and 4) a perceived lack of support from the provider. These findings show that individuals had pre-programme struggles and a series of life events that constrained their good intentions, and whilst they were positive about the programme, they were critical of the support they received from providers to deal with their life circumstances. Conclusions: Policy makers and providers can act proportionately to ensure that programmes, such as the NHS LCD Programme pilot, recognise the circumstances and context of people’s lives, and take a more person-centred approach.

Re:Mission study. Evaluating the NHS Low Calorie Diet pilot - an overview of service user data collection methods

Introduction: The National Health Service (NHS) Low Calorie Diet (LCD) pilot programme aimed to support people with type 2 diabetes (T2DM) to lose weight, reduce glycaemia and potentially achieve T2DM remission using total diet replacement alongside behaviour change support. The Re:Mission study seeks to provide an enhanced understanding of the long-term cost-effectiveness of the programme and its implementation, equity, transferability and normalisation across broad and diverse populations. This article presents an overview of the methods used in the Re:Mission study. Methods and analysis: A mixed method approach was used to draw together service user insights from across longitudinal and cross-sectional online surveys and semi-structured interviews supported by a modified photovoice technique. Insights were captured from active service users across the three phases of the programme (total diet replacement, food reintroduction and maintenance) in addition to those discharged prematurely. Survey data were analysed using descriptive statistics and qualitative data were thematically analysed and interpreted through a realist informed lens to understand which aspects of the service work and do not work, for whom, in what context and why. Results: Results from the study are presented elsewhere, with recommendations for policy practice and research.

“Trying to make healthy choices”: the challenges of the food reintroduction phase of the NHS Low Calorie Diet Programme pilot for type 2 diabetes

Background: The food reintroduction phase of the NHS Low Calorie Diet (LCD) programme aims to support service users to reintroduce food gradually back into their diet. Understanding experiences of food reintroduction from a broad and diverse range of service users is critical in helping to improve service delivery and commissioning and equity in care. Methods: This was a co-produced qualitative study underpinned by a realist informed approach, using interviews and photovoice techniques. Service users (n=43) of the NHS LCD Programme were recruited from three delivery models across 21 pilot sites in England. Data were analysed using a thematic approach. Results: The food introduction phase required control and planning that challenged the behaviours of participants. Around a third of participants continued use of Total Diet Replacement products, or considered doing so, for convenience and to maintain calorie control. The coach–service user relationship was important to understanding of session content and translation into behaviour change. Physical activity increased during this phase, which contributed to positive health outcomes. Conclusions: The paper reports insights from the food reintroduction phase of the LCD programme. Key messages include the need for increased frequency of support and the need for tailored and culturally representative education.

‘Life changing or a failure’? Qualitative experiences of service users from the weight maintenance phase of the NHS Low Calorie Diet Programme pilot for type 2 diabetes

Background: The weight maintenance phase of the NHS Low CalorieaDiet (LCD) programme focuses on embedding long- term dietary and physical activity changes. Understanding individual experiences of this phase is crucial to exploring long- term effectiveness and equity of the intervention approach. Methods: This was a coproduced qualitative study underpinned by a realist informed approach, using interviews and photovoice techniques. Service users (n=25) of the NHS LCD programme were recruited from three delivery models, across 21 sites in England. Data were analysed using a thematic approach. Results: The experiences reported were largely positive, with many participants reporting changes in their diet and physical activity. Some service users expressed a need for additional support and there appeared variation in their experiences of the service providers and the wider available support network. Fear of weight regain and its glycaemic consequences was expressed by many; various mitigations were employed, including participating in other weight loss services and continuing use of Total Diet Replacement products. Conclusions: The NHS LCD programme has been life-changing for some people. However, service user insights suggest that a stronger person-centred focus might further improve effectiveness and service user experience.

Participant experiences during the NHS Low Calorie Diet Programme pilot. Findings from an online survey

Background: In 2020, NHS England commissioned independent commercial service providers to deliver a Low Calorie Diet Programme pilot, offering Total Diet Replacement alongside behavioural support. Methods: This paper presents participant experiences of the programme using both quantitative and qualitative data derived from four cross-sectional surveys, and examines differences by sociodemographics, delivery model and provider. Results: The majority of participants reported a positive experience with the referral process, with a small proportion feeling that insufficient information was provided and that they did not feel respected or listened to by their healthcare professional. Participants’ relationship with their coach was generally positive throughout each phase of the programme, and highlights the importance of coach-participant relationships. The relationship with the coach via digital delivery was less favourable compared to other delivery models, as was the perceived adequacy of support provided. Conclusions: The experience of the referral from general practice and the relationship with the coach are key elements of the participant experience. They demonstrate the importance of, and need for, person-centred care.

Addition of very low calorie diet (VLCD) during initiation of semaglutide in individuals with type 2 diabetes – interim results

Addition of very low calorie diet (VLCD) during initiation of semaglutide in individuals with type 2 diabetes – interim results

Change in symptoms of depression and eating disorders in adolescents with obesity participating in a clinical trial

Depression and eating disorder (ED) risk are heightened during adolescence(1) and both were exacerbated during COVID-19 lockdowns. This analysis reports changes in self-reported symptoms of depression and eating disorders throughout the Fast Track to Health trial. Fast Track to Health was a 52-week multi-site randomised-controlled trial, conducted 2018-2023, comparing intermittent (IER) and continuous energy restriction (CER) in adolescents with obesity and ≥1 associated comorbidity(2). The Centre for Epidemiologic Studies Depression Scale-revised 10-item version for adolescents (CESDR) was used to assess symptoms of depression (no symptoms, sub-threshold, or possible, probable, major depressive episode). Eating Disorder Examination Questionnaire (EDE-Q) was used to assess ED risk; defined as global score ≥2.7, ≥2 episodes of binge eating with/without loss of control, or ≥1 episode of purging within the last 28-days. The Binge Eating Scale (BES) assessed severity of binge eating (no binge eating, mild/moderate, severe). Adolescents were monitored for disordered eating during dietetic consults. Linear mixed models, retaining all data consistent with intention-to-treat analysis, were used to estimate the change in outcomes from baseline to week-52. Descriptive statistics were used to describe the number of participants meeting screening criteria at baseline and week-52. One hundred and forty one adolescents were enrolled and 97 completed the trial, with median (IQR) EDE-Q score 2.28 (1.43 to 3.14), CESDR 9.00 (4.0 to 14.5) and BES 11.0 (5.0 to 17.0) at baseline. EDE-Q (change in estimated marginal means [SE], IER −0.63 [0.18], CER −0.56 [0.17]) and CESDR (IER −2.70 [1.15], CER −3.87 [1.07]) scores reduced between baseline and week-52 in both groups (p<0.05) with no difference between groups. There was a between group difference (p = 0.019) in change in BES. The IER group had a reduction between baseline and week-52 (−3.72 [1.27]) and the CER group had no change. At baseline, 31 (22%) adolescents were classified as having a possible/probable/major depressive episode, 110 (78%) met ≥1 ED criteria and 28 (21%) as mild/moderate or severe binge eating, reducing to 8 (9%), 56 (61%) and 15 (16%) respectively at week-52. A small sub-group of adolescents required additional support for disordered eating. Overall, treatment-seeking adolescents with obesity have symptoms of depression and ED. Although symptoms reduce for most, some required additional support. Screening and monitoring for depression and ED are important to ensure early intervention.

Effect of a Low-Calorie Dietary Intervention on Liver Health and Body Weight in Adults with Metabolic-Dysfunction Associated Steatotic Liver Disease (MASLD) and Overweight/Obesity: A Systematic Review and Meta-Analysis.

Metabolic-dysfunction Associated Steatotic Liver Disease (MASLD) is a common cause of chronic liver disease. This review assessed the efficacy of a Low-Calorie Diet (LCD) on liver health and body weight in people living with MASLD and obesity. The study was registered with PROSPERO (CRD42021296501), and a literature search was conducted using multiple databases. The key inclusion criteria were randomised controlled trials or cohort studies, obesity/overweight and MASLD. Two authors screened abstracts, reviewed full texts and performed data extraction and quality assessment. The primary outcome was the change in the serum ALT, and secondary outcomes included the changes in the serum AST, intrahepatic lipid content (IHL), quantified non-invasively via MRI/MRS, and body weight. Fifteen studies were included. The LCD reduced body weight by 9.1 kg versus the control (95%CI: -12.4, -5.8) but not serum ALT (-5.9 IU/L, -13.9, 2.0). Total Dietary Replacement (TDR) reduced IHL by -9.1% vs. the control (-15.6%, -2.6%). The Mediterranean-LCD for ≥12 months reduced ALT (-4.1 IU/L, -7.6, -0.5) and for 24 months reduced liver stiffness versus other LCDs. The Green-Mediterranean-LCD reduced IHL, independent of body weight. Limited studies assessed those of Black or Asian ethnicity, and there was heterogeneity in the methods assessing the liver fat content and fibrosis. In people with MASLD and obesity, an LCD intervention reduces IHL and body weight. Trials should focus on the recruitment of Black and Asian ethnicity participants.

548 Metformin normalizes impaired renal and cardiac function in a rat model of transient undernutrition

OBJECTIVES/GOALS: In the U.S., over 4 million people including children experience transient periods of undernutrition annually. Cardio-metabolic and renal diseases are more prevalent in this population. We are investigating therapeutic strategies to reverse the long-term risk of these diseases in a rat model of transient undernutrition followed by refeeding. METHODS/STUDY POPULATION: Thirty six female Fischer rats (3-months of age) were initially divided into 2 groups. Half were fed regular chow (CT) while the other half were severely food restricted (sFR) by 60% from 0-2 weeks (wks) followed by refeeding from 2-14 wks (sFR-Refed). These 2 groups were then subdivided and treated ± metformin (Met) from wk 7 to wk 12 (n=9/group). High precision ultrasound was conducted on live rats to assess heart and kidney function immediately after the sFR period ended (wk 2) and at the end of the study (wk 14). At the conclusion of the experiment, the rats were sacrificed and the histology of the kidney and heart tissues were analyzed in hematoxylin and eosin-stained sections. The protein to DNA ratio was also calculated in homogenates from these tissues. RESULTS/ANTICIPATED RESULTS: In sFR-Refed rats, cardiac output (CO), heart rate (HR) and renal artery blood flow (RBF) were decreased by 11 ± 1.5%#, 7.0 ± 6.0% and 22 ± 0.6%#, respectively, compared to control (CT) rats; #p<0.05. Mean glomerular diameter was reduced in the kidneys of sFR-refed rats compared to CT and this effect was attenuated by metformin treatment [(µm): CT, 406 ± 31; sFR-Refed, 383 ± 11, p<0.06; CT+Met, 393 ± 18; sFR-Refed+Met, 407 ± 18*]. Furthermore, the mean cardiomyocyte thickness was reduced in sFR-Refed rats compared to controls while metformin treatment prevented this effect [(µm): CT, 16.4 ± 3.6; sFR-Refed, 11.5 ± 2.3#; CT+Met, 16.4 ± 3.6; sFR-Refed+Met, 15.9 ± 3.2*]. #p<0.05 vs. CT, same treatment; *p<0.05 vs. Met, same diet; two-way ANOVA. DISCUSSION/SIGNIFICANCE: These findings have promising implications for metformin use to mitigate long-term impairments in heart and kidney structure and function in individuals who have experienced bouts of undernutrition earlier in life for either voluntarily (e.g., very low calorie dieting) or involuntary (e.g., very low food security) reasons.

Are Most Videos Published on Youtube™ About Weight Loss and Low-Calorie Diet Made by Healthcare Professionals?

Background and Aims: Nowadays, people have become embracing the use of web-based technologies for communication and educational purposes. There are studies that prove the effectiveness that computer-, internet- or multimedia-based educational methods are more effective than traditional, paper-based sources. Therefore, evaluating if YouTube™ about weight loss or low-calorie diet video was shared by a healthcare professional could facilitate the identification of authentic information sources and real knowledge transfer. Thus, the study objective was to mathematically and objectively evaluate the number of videos shared on YouTube™ about weight loss and low-calorie diet produced by healthcare or non-health professionals. Methos: Was conducted systematic search for videos that contain relevant information about weight loss and low-calorie diet on the YouTube™ video platform. The author used two terms for the search, it was "weight loss" and "low calorie diet". Thus, with this approach, the study purpose was to find videos with the weight loss and low-calorie diet themes about and to assess if were made by professionals or non-professional health care. Results: 130 videos were then selected for the research. Of the total, 12 were not in English and 4 were newspaper, magazine, or news videos. Thus, 114 videos were elective for subsequent analyses, where 76 explained about weight loss self-reports, 12 it talked about weight loss training routines, 22 explained about weight loss low-calorie models’ diet and 4 commented on medication weight loss. Still regarding the 114 total videos, 16 were produced by healthcare professionals (16%) and 98 by non-healthcare professionals. Conclusion: In summary, 16% weight loss or low-calorie diet videos were shared by healthcare professionals e 75% weight loss or low-calorie diet total videos views were shared by non-healthcare professionals.

Lutein in chronic diseases: A mini review

Lutein is a xanthophyll carotenoid that can be found in a divergency of fruits and plants. Its main action is to protect eye health and vision. Its antioxidant properties play a crucial role in eye agitations, in decreasing inflammation, in protecting the neural tissues from chemical analyzed hypoxia and cell apoptosis. Lutein supplementation in associa- tion with low-calorie diet had a notable abatement in fat-free mass, visceral fat and serum levels of total cholesterol and LDL (low-density lipoprotein)-cholesterol. Lutein may also have a natural anti-cancer effect. This is because foods rich in lutein have antioxidant activity and oppose inflammation and oxidative stress. The aim of this mini-review was to provide an up-to-date overview of the main effects of lutein in health and disease.

Exercise Combined with a Low-Calorie Diet Improves Body Composition, Attenuates Muscle Mass Loss, and Regulates Appetite in Adult Women with High Body Fat Percentage but Normal BMI.

The present study aimed to examine the effects of a 500 kcal reduction in daily energy intake alone and in combination with 90 min of moderate-to-vigorous aerobic exercise per week on body weight, body composition, and appetite sensations in young women with normal BMI and abnormal body fat percentage. sixty-six young women with normal BMI and abnormal body fat percentage (21.33 ± 1.20 kg/m2 and 34.32 ± 2.94%) were randomly assigned into three groups: (1) caloric restriction (CR; n = 22), (2) caloric restriction with exercise (CR-EX; n = 22), and (3) control (C; n = 22). Data on anthropometry, blood samples, and subjective appetite sensations pre- and post-intervention were collected. After 4 weeks of intervention, CR and CR-EX groups both reduced body weight, fat percentage, and waist and hip circumferences compared to the C group (p < 0.05). Muscle mass of the CR group was significantly lower than that of the C group (-1.21 ± 0.86 kg vs. -0.27 ± 0.82 kg, p < 0.05), and no significant difference between CR-EX and C groups was observed. For appetite sensations, the subjects of the CR group showed significant increases in change of scores in desire to eat and prospective consumption than that of the C group (p < 0.05), while no significant difference between CR-EX and C groups was observed. A 500 kcal reduction in daily energy intake alone and in combination with 90 min of moderate-to-vigorous aerobic exercise per week could both reduce weight and improve body composition in young adult women with normal BMI and abnormal body fat percentage. More importantly, calorie restriction combined with exercise intervention was superior to calorie restriction alone in improving muscle mass loss and regulating appetite sensations.

High Fat Diet and Polycystic Ovary Syndrome (PCOS) in Adolescence: An Overview of Nutritional Strategies.

Polycystic ovary syndrome (PCOS) is a multifaceted and heterogeneous disorder, linked with notable reproductive, metabolic, and psychological outcomes. During adolescence, key components of PCOS treatment involve weight loss achieved through lifestyle and dietary interventions, subsequently pursued by pharmacological or surgical therapies. Nutritional interventions represent the first-line therapeutic approach in adolescents affected by PCOS, but different kinds of dietary protocols exist, so it is necessary to clarify the effectiveness and benefits of the most well-known nutritional approaches. We provided a comprehensive review of the current literature concerning PCOS definition, pathophysiology, and treatment options, highlighting nutritional strategies, particularly those related to high-fat diets. The high-fat nutritional protocols proposed in the literature, such as the ketogenic diet (KD), appear to provide benefits to patients with PCOS in terms of weight loss and control of metabolic parameters. Among the different types of KD studies, very low-calorie ketogenic diets (VLCKD), can be considered an effective dietary intervention for the short-term treatment of patients with PCOS. It rapidly leads to weight loss alongside improvements in body composition and metabolic profile. Even though extremely advantageous, long-term adherence to the KD is a limiting factor. Indeed, this dietary regimen could become unsustainable due to the important restrictions required for ketosis development. Thus, a combination of high-fat diets with more nutrient-rich nutritional regimens, such as the Mediterranean diet, can amplify positive effects for individuals with PCOS.

Effect of Diet before Bariatric Surgery on Ghrelin Level through DNA Methylation

Introduction: The ghrelin system, which generates the appetite hormone, is harmed by obesity, a problem of worldwide public health. An efficient way to cure obesity is through bariatric surgery. This randomized controlled study’s objective was to assess preoperative diet-related DNA methylation of Ghrelin (GHRL) levels in patients undergoing bariatric surgery. Methods: The 50 patients who volunteered to participate in the trial were randomly divided into two groups. The study group followed the very low-calorie diet for 2 weeks. The control group did not follow any diet. The physiological parameters, weight, and DNA methylation levels of the patients were assessed. Results: The percentage of excess weight loss (EWL) in the control and study groups was determined as 47.1% and 51.5%, respectively. The study group’s GHRL percentage of methylated reference was 76.8%, whereas the control group’s was 67.3%. It was concluded that the EWL and GHRL gene DNA methylation of the diet-treated study group were significantly higher than the control group (p < 0.05). Conclusion: According to the findings, the pre-op diet had a favorable effect on the patient’s behavior modification. It has also been shown to increase postoperative weight loss and DNA methylation of the Ghrelin gene. The ghrelin gene has been muted by methylation, making hunger regulation more manageable.

O255: Is a low calorie "liver shrinking" diet predictive of long term weight loss and metabolic improvement after sleeve gastrectomy?

Abstract Introduction Limited evidence exists regarding pre-operative “liver shrinking” diet, but a two-week period of low calorie diet (LCD) is mandated before bariatric surgery, with weight outcomes rarely measured. Longer periods of LCD can ameliorate obesity, diabetes and metabolic-associated-fatty-liver disease (MAFLD). Primary aim to determine if response to LCD is predictive of long-term weight loss. Secondary aim to determine if alteration in liver function, and MAFLD, correlate with weight change after diet/ in follow up. Methodology Patients undergoing sleeve gastrectomy recruited and weight, blood plasma and 16S rRNA faecal microbiome profile recorded at baseline, following two-week LCD and at six-months, with liver biopsy at surgery (6). Results First nine patients had median baseline BMI 47.3kg/m2, and 34.7 kg/m2 at 6-months (-12.3kg/m2). Median excess weight loss was 8.6% (6.35kg) after LCD and 47.57% (34.65kg) at 6-months. Spearman’s Rank Correlation was weakly positive (0.5) for absolute weight loss between LCD and follow up, and was 0.25 using excess weight loss (non-significant). Change in liver function and MAFLD grade did not correlate with weight loss following LCD and at 6-months. Conclusions Weight loss response to LCD correlated poorly with long-term weight loss (analysing by absolute/ excess weight). Liver health and MAFLD did not predict 6-month weight loss. A dramatic response to LCD may not manifest in longer term metabolic improvement after surgery. We will also report on faecal microbiome; it appears more complex mechanisms underpin weight change and response to dietary manipulation in the surgical cohort than can be extrapolated from population studies.

Higher-Level Steatosis Is Associated with a Greater Decrease in Metabolic Dysfunction-Associated Steatoic Liver Disease after Eight Weeks of a Very Low-Calorie Ketogenic Diet (VLCKD) in Subjects Affected by Overweight and Obesity.

The most common form of chronic liver disease, recently defined as MASLD, is strongly linked to obesity and metabolic syndrome. Lifestyle changes are part of MASLD prevention. The very low-calorie ketogenic diet (VLCKD) is a useful option for treating MASLD and reducing liver steatosis in patients with obesity. We assessed whether a greater degree of steatosis could have a positive or negative impact on how well 8 weeks of using the VLCKD improve steatosis and fibrosis in a patient population of overweight and obese individuals. Anthropometric parameters, along with changes in hormone and metabolic biomarkers, were also assessed both before and after the dietary change. The study population included 111 overweight (14.41%) or obese subjects (85.59%) aged between 18 and 64 years; the 75 women and 36 men involved were not taking any medicine. In both the raw (0.37 95% CI 0.21; 0.52) and the multivariate models (model a: 0.439 95% CI 0.26; 0.62; model b: 0.437 95% CI 0.25; 0.63), there was a positive and statistically significant correlation between the CAP delta value and the CAP before using the VLCKD. Additionally, the liver stiffness delta was found to be positively and statistically significantly correlated with liver stiffness before the use of the VLCKD in both models: the multivariate model (model a: 0.560 95% CI 0.40; 0.71; model b: 0.498 95% CI 0.34; 0.65) and the raw model (0.52 95% CI 0.39; 0.65). Systolic and diastolic blood pressure, insulin resistance (measured by HOMA-IR), insulin, HbA1c, fasting blood glucose, total cholesterol, LDL cholesterol, HDL cholesterol and triglycerides, BMI, waist circumference, and fat mass, were all decreased (p < 0.001) following the use of the VLCKD. However, following the use of the VLCKD, there was an increase in vitamin D levels. (p < 0.001). We found that using the VLCKD for 8 weeks has a greater effect on improving steatosis and fibrosis in subjects who initially have more severe forms of these conditions.