Effectiveness of weight loss interventions--is there a difference between men and women: a systematic review

MicroRNA in cardiometabolic health and disease: The perspectives of sex, gender and personalised medicine

BACKGROUND

Personalized medicine represents a novel and integrative approach that focuses on an individual's genetics and epigenetics, precision medicine, lifestyle and exposures as key players of health status and disease phenotypes.

METHODS

In this narrative review, we aim to carefully discuss the current knowledge on gender disparities in cardiometabolic diseases, and we consider the sex- specific expression of miRNAs and their role as promising tool in precision medicine.

RESULTS

Personalised medicine overcomes the restricted care of patient based on a binomial sex approach, by enriching itself with a holistic and dynamic gender integration. Recognized as a major worldwide health emergency, cardiometabolic disorders continue to rise, impacting on health systems and requiring more effective and targeted strategies. Several sex and gender drivers might affect the onset and progression of cardiometabolic disorders in males and females at multiple levels. In this respect, distinct contribution of genetic and epigenetic mechanisms, molecular and physiological pathways, sex hormones, visceral fat and subcutaneous fat and lifestyle lead to differences in disease burden and outcomes in males and females.

CONCLUSIONS

Sex and gender play a pivotal role in precision medicine because the influence the physiology of each individual and the way they interact with environment from intrauterine life.

Hypogonadism and nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD), recently proposed to be renamed to metabolic dysfunction-associated steatotic liver disease (MASLD), is a major global public health concern, affecting approximately 25-30% of the adult population and possibly leading to cirrhosis, hepatocellular carcinoma, and liver transplantation. The liver is involved in the actions of sex steroids via their hepatic metabolism and production of the sex hormone-binding globulin (SHBG). Liver disease, including NAFLD, is associated with reproductive dysfunction in men and women, and the prevalence of NAFLD in patients with hypogonadism is considerable. A wide spectrum of possible pathophysiological mechanisms linking NAFLD and male/female hypogonadism has been investigated. As therapies targeting NAFLD may impact hypogonadism in men and women, and vice versa, treatments of the latter may affect NAFLD, and an insight into their pathophysiological pathways is imperative. This paper aims to elucidate the complex association between NAFLD and hypogonadism in men and women and discuss the therapeutic options and their impact on both conditions.

Gender Differences in Liver Steatosis and Fibrosis in Overweight and Obese Patients with Metabolic Dysfunction-Associated Steatotic Liver Disease before and after 8 Weeks of Very Low-Calorie Ketogenic Diet

Obesity and metabolic syndrome are linked to steatotic liver disease (SLD), the most common form of chronic liver disease. Lifestyle modifications and dieting are strategies that can prevent metabolic dysfunction-associated steatotic liver disease (MASLD). The very low-calorie ketogenic diet (VLCKD) is a helpful treatment for MASLD and has been recommended for people affected by obesity; we evaluated the effect of gender on steatosis and fibrosis in a cohort of 112 overweight or obese patients undergoing an eight-week treatment with a VLCKD. Differences between the genders in terms of anthropometric measures, body composition, and metabolic indicators were examined before, during, and after the nutritional intervention. At baseline, there were significant differences between men and women in terms of anthropometric parameters, blood pressure, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR), fasting insulin, hepatic markers, and lipid profile. Men had considerably higher levels of liver steatosis (measured by CAP) and liver stiffness (measured by E) under basal conditions than women. After the VLCKD, there were reductions in both genders of controlled attenuation parameter (CAP), body weight, body mass index (BMI), waist circumference, systolic and diastolic blood pressure, insulin resistance, fat mass (FM), free fat mass (FFM), and fasting blood glucose, insulin, glycated hemoglobin (HbA1c), triglycerides, total cholesterol, low-density lipoprotein (LDL) cholesterol, alanine transaminase (ALT), gamma-glutamyl transferase (γGT), and uric acid levels. Only in men, liver stiffness, aspartate aminotransferase (AST), creatinine, and C-reactive protein (CRP) levels significantly decreased. Moreover, men had significantly greater levels of liver steatosis: the male gender featured an increase of 23.96 points of the Fibroscan CAP. Men exhibited higher levels of steatosis and fibrosis than women, and these differences persist despite VLCKD. These gender-specific variations in steatosis and fibrosis levels could be caused by hormonal and metabolic factors, suggesting that different therapeutic strategies might be required depending on the gender.

Female obesity: clinical and psychological assessment toward the best treatment

Obesity is a heterogeneous condition which results from complex interactions among sex/gender, sociocultural, environmental, and biological factors. Obesity is more prevalent in women in most developed countries, and several clinical and psychological obesity complications show sex-specific patterns. Females differ regarding fat distribution, with males tending to store more visceral fat, which is highly correlated to increased cardiovascular risk. Although women are more likely to be diagnosed with obesity and appear more motivated to lose weight, as confirmed by their greater representation in clinical trials, males show better outcomes in terms of body weight and intra-abdominal fat loss and improvements in the metabolic risk profile. However, only a few relatively recent studies have investigated gender differences in obesity, and sex/gender is rarely considered in the assessment and management of the disease. This review summarizes the evidence of gender differences in obesity prevalence, contributing factors, clinical complications, and psychological challenges. In addition, we explored gender differences in response to obesity treatments in the specific context of new anti-obesity drugs.

Obesity management: sex-specific considerations

Obesity is a global health issue that has grown to epidemic proportions. According to World Health Organisation (WHO), overweight and obesity are responsible for more than 1.2 million deaths in Europe each year, representing > 13% of the region's total mortality. Highly processed, calorie-dense foods and reduced physical activity are considered as primary drivers of obesity, but genetic predisposition also plays a significant role. Notably, obesity is more prevalent in women than in men in most countries, and several obesity-related comorbidities exhibit sex-specific pathways. Treatment indication depends on BMI (body mass index), as well as existing comorbidities and risk factors. To reduce obesity-associated comorbidities, a permanent reduction in body weight of (at least) 5-10% is recommended. Treatment guidelines suggest an escalating stepwise approach including lifestyle intervention, pharmacotherapy, and bariatric-metabolic surgery. As cumulative evidence suggests differences in weight loss outcomes, there is growing interest in sex-specific considerations in obesity management. However, most trials do not report weight loss or changes in body composition separately for women and men. Here, we discuss state-of-the-art obesity management and focus on current data about the impact of sex on weight loss outcomes.

A service evaluation of more than 1 million self-funding adults attending a community weight management programme

Scaled interventions are required to address levels of overweight and obesity and reduce health inequalities. Little data is available on the effectiveness of community weight management programmes for participants self-selecting to attend across different socio-economic backgrounds. This analysis investigates 3, 6, and 12-month outcomes of adults joining a real-life community weight management programme. Weight, attendance and Indices of Multiple Deprivation (IMD) data from all fee-paying adults joining Slimming World in 2016 were collated. Data were analysed using descriptive and inferential statistics to determine predictors of weight loss. Mean BMI of 1 094 676 adults (7.6% male) was 33.0 ± 6.4 kg/m2. Mean % weight change at 3, 6, and 12 months was -5.0% ± 3.6%, -5.9% ± 5.2%, and -6.0% ± 5.8%. Those attending 75% sessions achieved greater weight loss with mean weight losses at 3, 6, and 12-months of 7.7% ± 3.3%, 11.3% ± 5.2%, and 14.1% ± 7.5%, respectively. Effect sizes from comparison of weight change between deprivation deciles were negligible, with similar outcomes in the most and least deprived deciles at 12-months (-5.7% ± 5.9% vs. -6.2% ± 5.9%). This service evaluation of more than 1 million adults attending a community weight management programme found they were able to achieve and/or maintain an average 6% weight loss at 12 months, with high attenders achieving >14% loss. Men and those with higher levels of deprivation were accessing the support and achieving significant weight losses. Slimming World as a real-life, scalable weight management programme is well placed to help adults manage their weight and address health inequalities.

Association between weight change, waist circumference change, and the risk of nonalcoholic fatty liver disease in individuals with metabolically healthy overweight or obesity and metabolically unhealthy overweight or obesity

BACKGROUND

This study aimed to explore and compare the effect of weight change, and waist circumference (WC) change, on the risk of nonalcoholic fatty liver disease (NAFLD) in individuals with metabolically healthy overweight or obesity (MHOW/O) and metabolically unhealthy overweight or obesity (MUOW/O) in a health check-up cohort in China.

METHODS

5625 adults with overweight or obesity, and free from NAFLD at baseline were included. Metabolically healthy was defined as not having any components of metabolic syndrome. Weight/WC changes were calculated as the relative difference between the first and second visits of check-up. NAFLD was assessed based on abdominal ultrasound.

RESULTS

During a median follow-up of 2.1 (IQR: 1.1-4.3) years, 1849 participants developed NAFLD. In MHOW/O participants, the multivariable adjusted HRs (95 % CIs) for NAFLD in weight change ≤ -5.0 %, and - 4.9-- 1.0 % were 0.36 (0.23-0.59), 0.59 (0.43-0.80), respectively, compared to the weight stable group (-0.9% to 0.9 %). The corresponding HRs (95 % CIs) for the association between WC change (≤ 6.0 %, - 5.9 to -3.0 %) and NAFLD in MHOW/O participants were 0.41 (0.27-0.62), and 0.74 (0.54-1.01), respectively, compared to the WC stable group (-2.9-2.9 %). Similar patterns were observed in MUOW/O participants. A more marked gradient of cumulative incidence of NAFLD across weight/WC change categories was observed in MHOW/O than in MUOW/O individuals.

CONCLUSIONS

A more evident association between weight/WC loss and risk of NAFLD was observed in MHOW/O than in MUOW/O individuals. Our findings indicate the practical significance of encouraging all individuals with overweight and obesity to achieve a clinically relevant level of weight/WC loss to prevent NAFLD, even among metabolic healthy groups.

Effectiveness of preconception weight loss interventions on fertility in women: a systematic review and meta-analysis

IMPORTANCE

Weight loss before conception is recommended for women with overweight or obesity to improve fertility outcomes, but evidence supporting this recommendation is mixed.

OBJECTIVE

To examine the effectiveness of weight loss interventions using lifestyle modification and/or medication in women with overweight or obesity on pregnancy, live birth, and miscarriage.

DATA SOURCES

An electronic search of MEDLINE, Embase, Cochrane Library, including Cochrane Database of Systematic Reviews and Cochrane Central Register of Controlled Trials, and Cumulative Index to Nursing and Allied Health Literature was conducted through July 6, 2022, via Wiley.

STUDY SELECTION AND SYNTHESIS

Randomized controlled trials examining weight loss interventions through lifestyle and/or medication in women with overweight or obesity planning pregnancy were included. Random-effects meta-analysis was conducted, reporting the risk ratio (RR) for each outcome. Subgroup analyses were conducted by intervention type, type of control group, fertility treatment, intervention length, and body mass index (BMI).

MAIN OUTCOME(S)

Clinical pregnancy, live birth, and miscarriage events.

RESULT(S)

A narrative review and meta-analysis were possible for 16 studies for pregnancy (n = 3,588), 13 for live birth (n = 3,329), and 11 for miscarriage (n = 3,248). Women randomized and exposed to a weight loss intervention were more likely to become pregnant (RR = 1.24, 95% CI 1.07-1.44; I2 = 59%) but not to have live birth (RR = 1.19, 95% CI 0.97-1.45; I2 = 69%) or miscarriage (RR = 1.17, 95% CI 0.79-1.74; I2 = 31%) compared with women in control groups. Subgroup analyses revealed women randomized to weight loss interventions lasting 12 weeks or fewer (n = 9, RR = 1.43; 95% CI 1.13-1.83) and women with a BMI ≥ 35 kg/m2 (n = 7, RR = 1.54; 95% CI, 1.18-2.02) were more likely to become pregnant compared with women in the control groups. Miscarriage was higher in intervention groups who underwent fertility treatment (n = 8, RR 1.45; 95% CI 1.07-1.96).

CONCLUSION(S)

Pregnancy rates were higher in women undergoing preconception weight loss interventions with no impact on live birth or miscarriage rates. Findings do not support one-size-fits-all recommendation for weight loss through lifestyle modification and/or medication in women with overweight or obesity immediately before conception to improve live birth or miscarriage outcomes.

Behavioural strategies to reduce obesity among lower socio-economic adults living in high-income countries: a Grades of Recommendation, Assessment, Development and Evaluation-assessed systematic review and meta-analysis of randomised controlled trials

Adult obesity disproportionately affects lower socio-economic groups in high-income countries and perpetuates health inequalities, imposing health and socio-economic burden. This review evaluates the effectiveness of behavioural strategies in reducing weight and cardiovascular disease (CVD) risks among low-income groups based in high-income countries. We searched major databases for randomised controlled trials published between 1 November 2011 and 1 May 2023. Meta-analyses and subgroup analyses were undertaken to analyse the pooled and individual effects of behavioural strategies. Cochrane Risk of bias (RoB 2·0) tool and Grades of Recommendation, Assessment, Development and Evaluation (GRADE) criteria were used to assess the quality and certainty of evidence. Fourteen trials (3618 adults, aged 40·2 ± 9·7 years with BMI 33·6 ± 2·8 kg/m2) and nine unique interventions were identified. Three trials with high RoB were omitted. Meta-analysis favoured interventions, demonstrating significant reductions in body weight (MD: -1·56 kg, (95 % CI -2·09, -1·03)) and HbA1c (MD: -0·05 %, (95 % CI - 0·10, -0·001)) at intervention end. Sub-group analysis showed no differences in waist circumference, blood pressure or serum lipids. Financial incentives and interactive feedback produced greatest amounts of weight losses ≥ 2 kg (GRADE: moderate). Behavioural strategies are effective weight loss interventions among lower socio-economic groups living in high-income nations. However, the impact on CVD risk remains unclear.

The effects of conjugated linoleic acid supplementation on anthropometrics and body composition indices in adults: a systematic review and dose-response meta-analysis

Prior meta-analytic investigations over a decade ago rather inconclusively indicated that conjugated linoleic acid (CLA) supplementation could improve anthropometric and body composition indices in the general adult population. More recent investigations have emerged, and an up-to-date systematic review and meta-analysis on this topic must be improved. Therefore, this investigation provides a comprehensive systematic review and meta-analysis of randomised controlled trials (RCT) on the impact of CLA supplementation on anthropometric and body composition (body mass (BM), BMI, waist circumference (WC), fat mass (FM), body fat percentage (BFP) and fat-free mass (FFM)) markers in adults. Online databases search, including PubMed, Scopus, the Cochrane Library and Web of Science up to March 2022, were utilised to retrieve RCT examining the effect of CLA supplementation on anthropometric and body composition markers in adults. Meta-analysis was carried out using a random-effects model. The I2 index was used as an index of statistical heterogeneity of RCT. Among the initial 8351 studies identified from electronic databases search, seventy RCT with ninety-six effect sizes involving 4159 participants were included for data analyses. The results of random-effects modelling demonstrated that CLA supplementation significantly reduced BM (weighted mean difference (WMD): -0·35, 95 % CI (-0·54, -0·15), P < 0·001), BMI (WMD: -0·15, 95 % CI (-0·24, -0·06), P = 0·001), WC (WMD: -0·62, 95% CI (-1·04, -0·20), P = 0·004), FM (WMD: -0·44, 95 % CI (-0·66, -0·23), P < 0·001), BFP (WMD: -0·77 %, 95 % CI (-1·09, -0·45), P < 0·001) and increased FFM (WMD: 0·27, 95 % CI (0·09, 0·45), P = 0·003). The high-quality subgroup showed that CLA supplementation fails to change FM and BFP. However, according to high-quality studies, CLA intake resulted in small but significant increases in FFM and decreases in BM and BMI. This meta-analysis study suggests that CLA supplementation may result in a small but significant improvement in anthropometric and body composition markers in an adult population. However, data from high-quality studies failed to show CLA's body fat-lowering properties. Moreover, it should be noted that the weight-loss properties of CLA were small and may not reach clinical importance.

Obesity: a gender-view

PURPOSE

There is a growing awareness of the importance of understanding gender differences in obesity. The aim of this short review was to revise the current evidence on anthropometric characteristics and nutritional and pharmacological aspects of obesity from a gender perspective.

METHODS

A literature search within PubMed was performed. Selected publications related to obesity and gender differences were reviewed.

RESULTS

The prevalence of obesity among men is higher than in women, but women have a higher percentage of body fat content compared to men, and gender appears to be an important factor in the manifestation of central (android) or peripheral (gynoid) obesity. In addition, while in most clinical trials, women are still underrepresented, in clinical registration trials of anti-obesity drugs, women are commonly up-represented and gender-specific analysis is uncommon. Considering that adipose tissue is one of the factors affecting the volume of distribution of many drugs, mainly lipophilic drugs, gender differences might be expected in the pharmacokinetics and pharmacodynamics of anti-obesity drugs. Indeed, although Liraglutide 3 mg, a long-acting glucagon-like peptide-1 receptor agonist, and naltrexone/bupropion display lipophilic properties, currently, a gender-dose adjustment for both these drugs administration is not recommended. In addition, despite that predicted responders to treatment offer substantial opportunities for efficient use, especially of expensive new therapies, such as anti-obesity drugs, data on gender differences to identify early responders to both these have not yet been investigated. Finally, bariatric surgery gender disparity reflects healthcare practices. Weight loss similar, but differing effects: women need more correction and face psychology challenges; men have worse physiology and fewer comorbidity improvements.

CONCLUSION

Gender differences exist in obesity prevalence and phenotype, body fat distribution, drug efficacy, clinical trial representation, and different secondary effects of bariatric surgery. Gender is an important variable in obesity analysis.

A complex relationship between intuitive eating and diet quality among university students

Intuitive Eating (IE) theory posits eating in response to internal hunger, and satiety cues minimize impulses to over-consume foods. To assess this relationship, 758 university students (55% male) completed the Intuitive Eating Scale 2 (IES-2) and the Diet History Questionnaire II (DHQ). The IES-2 includes a total score and four subscale scores; unconditional permission to eat (UPE), reliance on hunger and satiety cues (RHSC), eating for physical rather than emotional reasons (EPR), and body food choice congruence (BFCC). Using multiple regression analysis, IE total was not related to diet quality. EPR (ß =0.10, p ≤ .01) and BFCC (ß =0.29, p ≤ .001) were positively related to diet quality. UPE (ß = -0.15, p ≤ .001) and RHSC (ß = -0.08, p ≤ .05) were negatively related to diet quality. This study found an antipodal relationship between the subscales of IE and diet quality among university students.

Examining paradoxical session attendance and weight loss relationships in a clinic based lifestyle modification intervention

Objective

Evaluations of lifestyle modification interventions (LMIs), modeled after the Diabetes Prevention Program, have repeatedly shown a dose-response relationship between session attendance and weight loss. Despite this, not all participants had "average" weight loss experiences. Nearly one-third of LMI participants experienced unexpected, paradoxical outcomes (i.e., high attendance with little weight loss, and low attendance with clinically significant weight loss). Paradoxical weight-loss outcomes were characterized based on session attendance among participants in a group-based LMI in a real-world healthcare setting. This group-based LMI was delivered over 1 year to participants with the possibility of attending up to 25 sessions total.

Methods

LMI participants identified in 2010-2017 from electronic health records were characterized as having low (<75%) or high (≥75%) session attendance. Weight-loss outcomes were defined as expected (≥5%, high-attendance; <5%, low-attendance) or paradoxical (≥5%, low-attendance; <5%, high-attendance). Paradoxical-outcome-associated characteristics were identified using logistic regression.

Results

Among 1813 LMI participants, 1498 (82.6%) had low and 315 (17.4%) high session attendance; 555 (30.6%) had paradoxical outcomes, comprising 415 (74.8%) responders (≥5% weight-loss) and 140 (25.2%) non-responders (<5% weight-loss). Among participants with high session attendance, paradoxical non-responders were more likely to be female (odds ratio [OR]: 2.76; 95% confidence interval [CI]: 1.32, 5.77) and have type 2 diabetes (OR: 3.32; 95% CI: 1.01, 10.95). Among low-attendance participants, paradoxical responders were more likely to be non-Hispanic White and less likely to be non-Hispanic Black (OR: 0.35; 95% CI: 0.18, 0.69), non-Hispanic Asian (OR: 0.40; 95% CI: 0.22, 0.73), or Hispanic (OR: 0.53; 95% CI: 0.35, 0.80).

Conclusions

In a healthcare setting, nearly one-third of LMI participants experienced paradoxical outcomes. More research is needed to understand the facilitators and barriers to weight loss above and beyond session attendance.

Motivations for participation in weight loss clinical trials

Males are under-represented in weight loss clinical trials, usually comprising fewer than one-quarter of participants. Our study aimed to investigate people's motivations for participating in weight loss trials and determine any relationship with gender. Eighty individuals from an existing registry for weight loss trials were contacted, of whom 24 (9 males, 15 females) agreed to participate in a 20-min semi-structured interview around their expectations and motivations for volunteering. Interviews were audio-recorded and transcribed in Zoom. A transcript of each interview was uploaded into NVivo for preliminary thematic analysis. Improved health was a common motivation for pursuing weight loss in all subjects regardless of gender. Male recruitment to weight loss trials was often influenced by advice from a healthcare professional to lose weight for the prevention of obesity-related comorbidities, whereas family and aesthetic expectations (e.g., clothes and fashion) were key elements of female participation. Identification of gender differences in motivations for volunteering in weight loss trials will help improve tailoring of recruitment strategies and interventions to enhance male participation in the future.

A survey on the awareness, current management, and barriers for non-alcoholic fatty liver disease among the general Korean population

Non-alcoholic fatty liver disease (NAFLD) is often diagnosed incidentally during medical evaluation for diseases other than liver disease or during health checkups. This study aimed to investigate the awareness, current status, and barriers to the management of NAFLD in the general population. This cross-sectional study used an online survey, which consisted of 3-domain and 18-item questionnaires. The content validity index for each item of the questionnaire was rated above 0.80. Most respondents (72.8%) reported having heard of the term 'NAFLD', and a large proportion of the general population (85.7%) recognized the possibility of developing fatty liver without consuming alcohol. Awareness of the terminology of NAFLD and that NAFLD is a disease that needs to be managed is relatively high. However, the knowledge that NAFLD can progress to end-stage liver disease and new cardiovascular diseases is lacking. Only 25.7% of the general population is aware that NAFLD increases the incidence of heart and cerebrovascular diseases. Only 44.7% of those who were incidentally diagnosed during a health check-up were provided with any specific guidance on NAFLD, and more than half (55.3%) were not provided with education or guidance on NAFLD or did not remember it. Only 40.2% of people diagnosed with NAFLD incidentally visited a clinic. The reason for not visiting a clinic for the evaluation of NAFLD varied greatly depending on sex and age group. Only 40.2% of patients visited the clinic after being diagnosed with NAFLD. The reasons for not visiting the clinic after NAFLD diagnosis differed significantly according to sex and age.

Intermittent fasting for adults with overweight or obesity

This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the effects of intermittent fasting for adults with overweight or obesity.

Behavioral and Psychological Factors Affecting Weight Loss Success

PURPOSE OF REVIEW

There is a large variability between individuals in the weight loss response to any given diet treatment, which fuels interest into personalized or precision nutrition. Although most efforts are directed toward identifying biological or metabolic factors, several behavioral and psychological factors can also be responsible for some of this interindividual variability.

RECENT FINDINGS

There are many factors that can influence the response to dietary weight loss interventions, including factors related to eating behavior (emotional eating, disinhibition, restraint, perceived stress), behaviors and societal norms related to age and sex, psychological and personal factors (motivation, self-efficacy, locus of control, self-concept), and major life events. The success of a weight loss intervention can be influenced by many psychological and behavioral constructs and not merely by physiological factors such as biology and genetics. These factors are difficult to capture accurately and are often overlooked. Future weight loss studies should consider assessing such factors to better understand the underlying reasons for the large interindividual variability to weight loss therapy.

Factors that predict weight loss success differ by diet intervention type

Background

Many types of diet intervention can achieve negative energy balance and successful weight loss in persons with obesity. However, within any dietary strategy, there is large inter-individual variation in the weight loss response. The aim of this study is to determine factors that predict weight loss success for diet interventions that vary by macronutrient and caloric composition.

Methods

Participants with BMI 30.0 to 49.9 kg/m2 self-selected one of three diet intervention trials for weight loss: low carbohydrate (LOW CHO), low fat (LOW FAT), or low calorie (LOW KCAL). Multivariable regression models were developed to determine the significance of predictor demographic, body composition, metabolic, clinical, and dietary variables for each diet type.

Results

Weight loss over 12-16 weeks averaging -5.1 ± 4.0 kg from baseline weight, p < 0.001, was not significantly different among diet types. Several different factors were identified that account for the inter-individual variance in weight loss success. Regardless of diet type, the most robust predictor of weight loss success was completion of the intervention, accounting for 20-30% of the variance. Factors predicting diet intervention completion were age, physical activity level, blood leptin level, blood pressure, and the amount of weight loss occurring. Differences by diet type in cardiometabolic risk factor reduction were identified with LOW CHO decreasing glycemia/insulinemia factors, LOW FAT decreasing lipidemia factors, and LOW KCAL decreasing inflammatory factors.

Conclusion

These data provide evidence to inform more precise and personalized approaches to diet intervention for weight loss and cardiometabolic health.

Health Coaching for Weight Loss Among Overweight and Obese Individuals in Saudi Arabia: A Retrospective Analysis

Background Health coaching is an increasingly used strategy to help in adopting lifestyle changes for weight loss. While Saudi Arabia has one of the highest obesity prevalences worldwide, research on lifestyle interventions for weight loss is limited. Aim We aimed to investigate the effectiveness of health coaching for weight loss among the Saudi population in real-world primary healthcare settings. Methods This is a retrospective observational study. Secondary data from the health coach national program in the Eastern Health Cluster were retrieved. Obese and overweight individuals aged 15 years or older with weight-related goals who completed at least 12 weeks of coaching were included in the analysis. The primary outcomes are weight change (kg) and weight change percent (%) of the initial weight. We further compared the weight change% between different follow-up methods (i.e., physical, virtual, and hybrid) and studied the factors associated with -5% weight loss. Results In total, 465 participants were included in the analysis, with a female predominance (66.2%) and a median initial weight of 90 kg (interquartile range (IQR): 77, 101). The median follow-up duration was 127 days (IQR: 101, 157), and the median total number of coaching sessions was three (IQR: 2, 5). The mean weight change was -2.68 kg (95% confidence interval (CI): -3.12, -2.24), p<0.001. Comparing each follow-up group, no statistically significant difference was found when controlling for number of visits (p=0.059). The adjusted means for weight change% were -3.77%, -2.59%, and -2.54% for hybrid, physical, and virtual visits, respectively. Factors that were associated with achieving at least -5% weight loss were male sex (adjusted odds ratio (aOR)=1.87, 95% CI: 1.16, 3.02), five or more total coaching visits (aOR=5.23, 95% CI: 2.88, 9.50), longer follow-up duration (aOR=1.09, 95% CI: 1.03, 1.15), and having a weight management goal (aOR=4.5, 95% CI: 1.63, 12.45) as the reason for initial coaching visit. Conclusion We found statistically significant weight change among clients who completed 12 weeks of coaching in primary care settings. The findings in this paper contribute to the importance of lifestyle interventions for weight loss among the Saudi population. However, stronger controlled studies are needed to confirm this finding.

Design of the CHARGE study: A randomized control trial evaluating a novel treatment for Veterans with binge eating disorder and overweight and obesity

A large number of Veterans experience binge eating and overweight or obesity, which are associated with significant health and psychological consequences. The gold-standard program for the treatment of binge eating, Cognitive Behavioral Therapy (CBT), results in decreases in binge eating frequency but does not result in significant weight loss. We developed the Regulation of Cues (ROC) program to reduce overeating and binge eating through improvement in sensitivity to appetitive cues and decreased responsivity to external cues, an approach that has never been tested among Veterans. In this study, we combined ROC with energy restriction recommendations from behavioral weight loss (ROC+). This study is a 2-arm randomized controlled trial designed to evaluate the feasibility and acceptability of ROC+, and to compare the efficacy of ROC+ and CBT on reduction of binge eating, weight, and energy intake over 5-months of treatment and 6-month follow-up. Study recruitment completed in March 2022. One hundred and twenty-nine Veterans were randomized (mean age = 47.10 (sd = 11.3) years; 41% female, mean BMI = 34.8 (sd = 4.7); 33% Hispanic) and assessments were conducted at baseline, during treatment and at post-treatment. The final 6-month follow-ups will be completed in April 2023. Targeting novel mechanisms including sensitivity to internal cures and responsivity to external cues is critically important to improve binge eating and weight-loss programs among Veterans. Clinicaltrials.govNCT03678766.

Potential contributors to variation in weight-loss response to liraglutide

Obesity treatment requires a chronic state of negative energy balance. Obesity medications can help with this, increasing long-term dietary compliance by promoting satiety or reducing hunger. However, efficacy and safety of obesity medications vary for individuals. Early identification of non-responders to obesity medications may limit drug exposure while optimizing benefits for responders. This review summarizes factors that impact weight-loss response to liraglutide. Factors linked to greater weight loss on liraglutide include being female, not having diabetes, having relatively high baseline weight, and losing at least 4% of initial weight after 16 weeks of treatment. Other covariates that may predict treatment response but require further confirmation include central effects, nausea, gastric emptying of solids, and genotype. Baseline body mass index, race, and age seem less relevant for predicting weight-loss response to liraglutide. Lesser known and harder-to-measure factors such as cerebral blood flow, food cue reactivity, gut hormone levels, and dietary adherence possibly impact variability of response to liraglutide. This information should assist healthcare providers with establishing realistic weight-loss probability for individual patients. Future research should improve the ability to identify responders to liraglutide. Importantly, this review may provide a framework to identify responders to other obesity medications.

Investigating the causal relationships between excess adiposity and cardiometabolic health in men and women

AIMS/HYPOTHESIS

Excess adiposity is differentially associated with increased risk of cardiometabolic disease in men and women, according to observational studies. Causal inference studies largely assume a linear relationship between BMI and cardiometabolic outcomes, which may not be the case. In this study, we investigated the shapes of the causal relationships between BMI and cardiometabolic diseases and risk factors. We further investigated sex differences within the causal framework.

METHODS

To assess causal relationships between BMI and the outcomes, we used two-stage least-squares Mendelian randomisation (MR), with a polygenic risk score for BMI as the instrumental variable. To elucidate the shapes of the causal relationships, we used a non-linear MR fractional polynomial method, and used piecewise MR to investigate threshold relationships and confirm the shapes.

RESULTS

BMI was associated with type 2 diabetes (OR 3.10; 95% CI 2.73, 3.53), hypertension (OR 1.53; 95% CI 1.44, 1.62) and coronary artery disease (OR 1.20; 95% CI 1.08, 1.33), but not chronic kidney disease (OR 1.08; 95% CI 0.67, 1.72) or stroke (OR 1.08; 95% CI 0.92, 1.28). The data suggest that these relationships are non-linear. For cardiometabolic risk factors, BMI was positively associated with glucose, HbA1c, triacylglycerol levels and both systolic and diastolic BP. BMI had an inverse causal relationship with total cholesterol, LDL-cholesterol and HDL-cholesterol. The data suggest a non-linear causal relationship between BMI and BP and other biomarkers (p<0.001) except lipoprotein A. The piecewise MR results were consistent with the fractional polynomial results. The causal effect of BMI on coronary artery disease, total cholesterol and LDL-cholesterol was different in men and women, but this sex difference was only significant for LDL-cholesterol after controlling for multiple testing (p<0.001). Further, the causal effect of BMI on coronary artery disease varied by menopause status in women.

CONCLUSIONS/INTERPRETATION

We describe the shapes of causal effects of BMI on cardiometabolic diseases and risk factors, and report sex differences in the causal effects of BMI on LDL-cholesterol. We found evidence of non-linearity in the causal effect of BMI on diseases and risk factor biomarkers. Reducing excess adiposity is highly beneficial for health, but there is greater need to consider biological sex in the management of adiposity.

Health effects of the time-restricted eating in adults with obesity: A systematic review and meta-analysis

Background

The number of people suffering from overweight or obesity has been steadily increasing in recent years. As a new form of diet, the efficacy of time-restricted eating (TRE) remains debatable.

Objective

This meta-analysis quantified the effect of TRE on weight change and other physical parameters in obese and overweight adults.

Methods

We did a systematic review and meta-analysis of randomized controlled trials (RCTs) comparing the TRE interventions on weight loss and other metabolic parameters by searching PubMed, Embase, and Cochrane Central Register of Controlled Trials to identify eligible trials published from database inception up until 23 August 2022. The risk of bias was assessed using the Revised Cochrane risk-of-bias tool (ROB-2.0). Meta-analysis was performed using Review Manager 5.4.1 software.

Results

Nine RCTs with 665 individuals (345 in the TRE group while 320 in the control group) were included. Results indicated that TRE had a greater decrease in body weight (-1.28 kg; 95% CI [-2.05, -0.52], p = 0.001), fat mass (-0.72 kg; 95% CI [-1.40, -0.03], p = 0.04), body mass index (-0.34 kg/m²; 95% CI [-0.64, -0.04], p = 0.03) and diastolic blood pressure (-2.26 mmHg 95% CI [-4.02, -0.50], p = 0.01). However, the meta-analysis demonstrated that there was no significant difference between TRE and the control group in lean mass, systolic blood pressure, waist circumference, fasting glucose, fasting insulin, homeostasis model assessment-insulin resistance (HOMA-IR), total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglycerides. Besides, the duration of the study and daily eating window also had an impact on weight change.

Conclusion

TRE was associated with reductions in weight and fat mass and can be a dietary intervention option for adults with obesity. But high-quality trials and longer follow-ups are needed to draw definitive conclusions.

Environmental Factors Determining Body Mass Index (BMI) within 9 Months of Therapy Post Bariatric Surgery-Sleeve Gastrectomy (SG)

Treatment of obesity should be multidirectional and include, in addition to bariatric surgery, changing the key factors of lifestyle and eating habits. The study aimed to assess the impact of bariatric surgery and dietary care on anthropometric measurements, blood pressure, changes in lifestyle, and eating habits of patients within 9 months after the procedure, with the selection of environmental factors determining BMI variation. The study included 30 SG patients before surgery (month zero) and at 1, 3, 6, and 9 months after SG. Patients completed a questionnaire regarding age, sex, place of residence, education, professional activity, number of family members, financial situation, family history of obesity, previous forms of therapy, self-assessment of nutritional knowledge, receiving and following nutritional recommendations, eating habits, frequency of body weight control, leisure time. Body weight, height, waist and hip circumference, and systolic and diastolic pressure were measured, and BMI and WHR (Waist to Hip Ratio) were calculated. Within 9 months after the procedure, the patients' body weight and BMI decreased on average by 26%. Post bariatric surgery, patients changed their eating habits. The influence of bariatric SG surgery and time after surgery was decisive for the normalization of BMI and explained the 33% variation in BMI up to 9 months after the procedure. Other factors important for the normalization of BMI after surgery were: male gender, older age of patients, family obesity (non-modifiable factors), as well as previous forms of therapy related to weight loss before surgery, shortening the intervals between meals and stopping eating at night (modifiable factors). The tested model explained 68% of the BMI variation after SG surgery for all assessed factors. Changes in lifestyle and eating habits in bariatric patients are crucial to maintaining the effect of bariatric surgery.

Sex differences in endocannabinoids during 3 years of Mediterranean diet intervention: Association with insulin resistance and weight loss in a population with metabolic syndrome

Background

Excess circulating endocannabinoids (eCBs) and imbalanced N-acylethanolamines (NAEs) related eCBs abundance could influence dietary weight loss success. We aimed to examine sex differences in the impact of a 3-years Mediterranean diet (MedDiet) intervention on circulating eCBs, NAEs and their precursor fatty acids, and to analyze the interplay between changes in eCBs or NAEs ratios, insulin resistance and the achievement of clinically meaningful weight reductions.

Methods

Prospective cohort study in a subsample of N = 105 participants (54.3% women; 65.6 ± 4.6 years) with overweight or obesity and metabolic syndrome that underwent a 3-years MedDiet intervention (PREDIMED-Plus study). Plasma eCBs and NAEs, including 2-arachidonoylglycerol (2-AG), anandamide (AEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), fatty acids, diet, glycemic homeostasis (including the assessment of insulin resistance-HOMA-IR), and cardiovascular risk markers were monitored (at 0-6-12-36 months).

Results

Mediterranean diet adherence increased in both sexes and remained high during the 3 years of follow-up. Reductions in body weight, glycemic and cardiovascular parameters were larger in men than in women. Women presented higher concentrations of NAEs than men throughout the study. In both sexes, AEA and other NAEs (including OEA, and PEA) decreased after 6 months (for AEA: −4.9%), whereas the ratio OEA/AEA increased after 1 year (+5.8%). Changes in 2-AG (−3.9%) and the ratio OEA/PEA (+8.2%) persisted over the 3 years of follow-up. In women, 6-months changes in AEA (OR = 0.65) and the ratio OEA/AEA (OR = 3.28) were associated with the achievement of 8% weight reductions and correlated with HOMA-IR changes (r = 0.29 and r = −0.34). In men, OEA/PEA changes were associated with 8% weight reductions (OR = 2.62) and correlated with HOMA-IR changes (r = −0.32).

Conclusion

A 3-years MedDiet intervention modulated plasma concentrations of eCBs and NAEs. Changes in AEA and in the relative abundance of NAEs were associated with clinically meaningful weight reductions. However, marked sex differences were identified in eCBs and NAEs, as well as in the efficacy of the intervention in terms of glycemic and cardiovascular parameters, which could be related to post-menopause alterations in glucose metabolism. These findings support a sex-balanced research strategy for a better understanding of the mechanisms underlying the regulation of body weight loss.

Changes in DNA Methylation of Clock Genes in Obese Adolescents after a Short-Term Body Weight Reduction Program: A Possible Metabolic and Endocrine Chrono-Resynchronization

Circadian rhythms are generated by a series of genes, collectively named clock genes, which act as a self-sustained internal 24 h timing system in the body. Many physiological processes, including metabolism and the endocrine system, are regulated by clock genes in coordination with environmental cues. Loss of the circadian rhythms has been reported to contribute to widespread obesity, particularly in the pediatric population, which is increasingly exposed to chronodisruptors in industrialized society. The aim of the present study was to evaluate the DNA methylation status of seven clock genes, namely clock, arntl, per1-3 and cry1-2, in a cohort of chronobiologically characterized obese adolescents (n: 45: F/M: 28/17; age ± SD: 15.8 ± 1.4 yrs; BMI SDS: 2.94 [2.76; 3.12]) hospitalized for a 3-week multidisciplinary body weight reduction program (BWRP), as well as a series of cardiometabolic outcomes and markers of hypothalamo-pituitary-adrenal (HPA) function. At the end of the intervention, an improvement in body composition was observed (decreases in BMI SDS and fat mass), as well as glucometabolic homeostasis (decreases in glucose, insulin, HOMA-IR and Hb1Ac), lipid profiling (decreases in total cholesterol, LDL-C, triglycerides and NEFA) and cardiovascular function (decreases in systolic and diastolic blood pressures and heart rate). Moreover, the BWRP reduced systemic inflammatory status (i.e., decrease in C-reactive protein) and HPA activity (i.e., decreases in plasma ACTH/cortisol and 24 h urinary-free cortisol excretion). Post-BWRP changes in the methylation levels of clock, cry2 and per2 genes occurred in the entire population, together with hypermethylation of clock and per3 genes in males and in subjects with metabolic syndrome. In contrast to the pre-BWRP data, at the end of the intervention, cardiometabolic parameters, such as fat mass, systolic and diastolic blood pressures, triglycerides and HDL-C, were associated with the methylation status of some clock genes. Finally, BWRP induced changes in clock genes that were associated with markers of HPA function. In conclusion, when administered to a chronodisrupted pediatric obese population, a short-term BWRP is capable of producing beneficial cardiometabolic effects, as well as an epigenetic remodeling of specific clock genes, suggesting the occurrence of a post-BWRP metabolic and endocrine chronoresynchronization, which might represent a "biomolecular" predictor of successful antiobesity intervention.

Evaluation under real-life conditions of a lifestyle intervention for diabetes prevention developed by the municipal health services of Madrid, Spain

The Diet, Physical Activity and Health (Alimentación, Actividad física y Salud, ALAS) program is an intervention implemented by the municipal health services of Madrid with the objective of reducing weight and preventing diabetes in high-risk population by improving diet and physical activity. The ALAS program combines individual visits with a 10-session group workshop that takes place over a 6-month period. This study evaluated the effectiveness of the ALAS intervention implemented under real-life conditions between 2016 and 2019. The intervention was evaluated with a pre- and post-intervention study with follow-up performed 6 and 12 months from the start of the program. The analyzed outcomes were a 5-10% reduction in the initial weight, body mass index (BMI), waist circumference and a change in glycemic status in prediabetic participants. Statistical models were adjusted by sociodemographic variables. The participants were recruited from municipal community health centers or referred by municipal occupational health services. Between 2016 and 2019, 1629 people participated in the program. At 6 months, 85% of the participants had lost weight; 43% had lost 5% or more of their initial weight, and 12% had lost 10% or more. Regarding BMI, 22.3% of participants who were initially obese were no longer obese, and 15.2% of the overweight participants achieved normal weight. A total of 35.1% of the prediabetic participants reverted to normoglycemic status. The intervention was found to be more effective for men, for those who completed the intervention and those who accessed the program through the occupational health route. Among the participants who accessed the intervention via the community, the intervention was more effective in those with a high educational level. The evaluation demonstrated the effectiveness of the ALAS program for reducing weight and the risk of developing Type 2 diabetes when applied under real-life conditions. The effectiveness of the intervention differed according to gender, access route and educational level of the participants.

Differences in weight loss outcomes for males and females on a low-carbohydrate diet: A systematic review

It has been widely demonstrated that there are a broad range of individual responses to all weight management regimens, often masked by reports of the mean. Identifying features of responders and non-responders to weight loss regimens enables a more tailored approach to the provision of weight management advice. Low-carbohydrate diets are currently popular, and anecdote suggests that males are more successful at losing weight using this approach. This is feasible given the physiological and socio-psychological differences between the genders. We analysed the extent and variation in weight change for males and females separately through a systematic search for all low-carbohydrate diet trials published since 1985. Very few studies compared weight loss outcomes by gender and, of those that did, most lacked supporting data. The majority of studies reported no gender difference but when a gender difference was found, males were more frequently reported as losing more weight than females on a low-carbohydrate diet. The lack of gender stratification in weight loss trials is concerning, as there are a range of gender-based factors that affect weight loss outcomes. This study highlights the importance of examining weight change for males and females separately, since as failure to do so may mask any potential differences, which, if detected, could assist with better weight loss outcomes.

Weight loss in a digital app-based diabetes prevention program powered by artificial intelligence

Objective

The National Diabetes Prevention Program (DPP) reduces diabetes incidence and associated medical costs but is typically staffing-intensive, limiting scalability. We evaluated an alternative delivery method with 3933 members of a program powered by conversational Artificial Intelligence (AI) called Lark DPP that has full recognition from the Centers for Disease Control and Prevention (CDC).

Methods

We compared weight loss maintenance at 12 months between two groups: 1) CDC qualifiers who completed ≥4 educational lessons over 9 months (n  =  191) and 2) non-qualifiers who did not complete the required CDC lessons but provided weigh-ins at 12 months (n  =  223). For a secondary aim, we removed the requirement for a 12-month weight and used logistic regression to investigate predictors of weight nadir in 3148 members.

Results

CDC qualifiers maintained greater weight loss at 12 months than non-qualifiers (M  =  5.3%, SE  =  .8 vs. M  =  3.3%, SE  =  .8; p  =  .015), with 40% achieving ≥5%. The weight nadir of 3148 members was 4.2% (SE  =  .1), with 35% achieving ≥5%. Male sex (β = .11; P  =  .009), weeks with ≥2 weigh-ins (β = .68; P < .0001), and days with an AI-powered coaching exchange (β = .43; P < .0001) were associated with a greater likelihood of achieving ≥5% weight loss.

Conclusions

An AI-powered DPP facilitated weight loss and maintenance commensurate with outcomes of other digital and in-person programs not powered by AI. Beyond CDC lesson completion, engaging with AI coaching and frequent weighing increased the likelihood of achieving ≥5% weight loss. An AI-powered program is an effective method to deliver the DPP in a scalable, resource-efficient manner to keep pace with the prediabetes epidemic.

The limitations of investigating appetite through circuit manipulations: are we biting off more than we can chew?

Disordered eating can underpin a number of debilitating and prevalent chronic diseases, such as obesity. Broader advances in psychopharmacology and biology have motivated some neuroscientists to address diet-induced obesity through reductionist, pre-clinical eating investigations on the rodent brain. Specifically, chemogenetic and optogenetic methods developed in the 21st century allow neuroscientists to perform in vivo, region-specific/projection-specific/promoter-specific circuit manipulations and immediately assess the impact of these manipulations on rodent feeding. These studies are able to rigorously conclude whether a specific neuronal population regulates feeding behaviour in the hope of eventually developing a mechanistic neuroanatomical map of appetite regulation. However, an artificially stimulated/inhibited rodent neuronal population that changes feeding behaviour does not necessarily represent a pharmacological target for treating eating disorders in humans. Chemogenetic/optogenetic findings must therefore be triangulated with the array of theories that contribute to our understanding of appetite. The objective of this review is to provide a wide-ranging discussion of the limitations of chemogenetic/optogenetic circuit manipulation experiments in rodents that are used to investigate appetite. Stepping into and outside of medical science epistemologies, this paper draws on philosophy of science, nutrition, addiction biology and neurophilosophy to prompt more integrative, transdisciplinary interpretations of chemogenetic/optogenetic appetite data. Through discussing the various technical and epistemological limitations of these data, we provide both an overview of chemogenetics and optogenetics accessible to non-neuroscientist obesity researchers, as well as a resource for neuroscientists to expand the number of lenses through which they interpret their circuit manipulation findings.

Age- and sex-specific effects of a long-term lifestyle intervention on body weight and cardiometabolic health markers in adults with prediabetes: results from the diabetes prevention study PREVIEW

AIMS/HYPOTHESIS

Lifestyle interventions are the first-line treatment option for body weight and cardiometabolic health management. However, whether age groups or women and men respond differently to lifestyle interventions is under debate. We aimed to examine age- and sex-specific effects of a low-energy diet (LED) followed by a long-term lifestyle intervention on body weight, body composition and cardiometabolic health markers in adults with prediabetes (i.e. impaired fasting glucose and/or impaired glucose tolerance).

METHODS

This observational study used longitudinal data from 2223 overweight participants with prediabetes in the multicentre diabetes prevention study PREVIEW. The participants underwent a LED-induced rapid weight loss (WL) period followed by a 3 year lifestyle-based weight maintenance (WM) intervention. Changes in outcomes of interest in prespecified age (younger: 25-45 years; middle-aged: 46-54 years; older: 55-70 years) or sex (women and men) groups were compared.

RESULTS

In total, 783 younger, 319 middle-aged and 1121 older adults and 1503 women and 720 men were included in the analysis. In the available case and complete case analyses, multivariable-adjusted linear mixed models showed that younger and older adults had similar weight loss after the LED, whereas older adults had greater sustained weight loss after the WM intervention (adjusted difference for older vs younger adults -1.25% [95% CI -1.92, -0.58], p<0.001). After the WM intervention, older adults lost more fat-free mass and bone mass and had smaller improvements in 2 h plasma glucose (adjusted difference for older vs younger adults 0.65 mmol/l [95% CI 0.50, 0.80], p<0.001) and systolic blood pressure (adjusted difference for older vs younger adults 2.57 mmHg [95% CI 1.37, 3.77], p<0.001) than younger adults. Older adults had smaller decreases in fasting and 2 h glucose, HbA1c and systolic blood pressure after the WM intervention than middle-aged adults. In the complete case analysis, the above-mentioned differences between middle-aged and older adults disappeared, but the direction of the effect size did not change. After the WL period, compared with men, women had less weight loss (adjusted difference for women vs men 1.78% [95% CI 1.12, 2.43], p<0.001) with greater fat-free mass and bone mass loss and smaller improvements in HbA1c, LDL-cholesterol and diastolic blood pressure. After the WM intervention, women had greater fat-free mass and bone mass loss and smaller improvements in HbA1c and LDL-cholesterol, while they had greater improvements in fasting glucose, triacylglycerol (adjusted difference for women vs men -0.08 mmol/l [-0.11, -0.04], p<0.001) and HDL-cholesterol.

CONCLUSIONS/INTERPRETATION

Older adults benefited less from a lifestyle intervention in relation to body composition and cardiometabolic health markers than younger adults, despite greater sustained weight loss. Women benefited less from a LED followed by a lifestyle intervention in relation to body weight and body composition than men. Future interventions targeting older adults or women should take prevention of fat-free mass and bone mass loss into consideration.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT01777893.

Gender Differences in Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) has currently emerged as the most common liver disorder in both developed and developing countries. It has been observed that NAFLD exhibits sexual dimorphism, and there is limited understanding on the sex differences in adults with NAFLD. Nonalcoholic fatty liver disease shows marked differences in prevalence and severity with regards to gender. There are considerable biological disparities between males and females attributed to differences in the chromosomal makeup and sex hormone levels, distinct from the gender differences resulting from the sociocultural influences that lead to differences in lifestyle, which have a significant impact on the pathogenesis of this complex disorder. A multitude of factors contributes to the gender disparities seen and need to be researched in-depth to better understand the mechanisms behind them and the therapeutic measures that can be taken. In this article, we will review the gender disparities seen in NAFLD, as well as recent studies highlighting certain gender-specific factors contributing to its varying prevalence and severity.

HOW TO CITE THIS ARTICLE

Nagral A, Bangar M, Menezes S, et al. Gender Differences in Nonalcoholic Fatty Liver Disease. Euroasian J Hepato-Gastroenterol 2022;12(Suppl 1):S19-S25.

Effect of a Weight Loss and Lifestyle Intervention on Dietary Behavior in Men with Obstructive Sleep Apnea: The INTERAPNEA Trial

This study investigated the effects of an eight-week interdisciplinary weight loss and lifestyle intervention on dietary behavior in men who were overweight/had obesity and moderate-to-severe obstructive sleep apnea (OSA). It was based on data from INTERAPNEA (ClinicalTrials.gov ID: NCT03851653); a randomized clinical trial conducted from April 2019 to April 2020. Men aged 18–65 years with moderate-to-severe OSA and a body mass index ≥25 kg/m2 were randomly assigned to a usual-care group or an eight-week interdisciplinary weight loss and lifestyle intervention combined with usual-care. Dietary behavior was assessed through the Food Behavior Checklist (FBC) and the Mediterranean Diet Adherence Screener (MEDAS). Of the 89 participants who underwent randomization, 75 completed the intervention endpoint assessment, 89 participants being therefore included in the intention-to-treat analyses, and 75 in the per-protocol approach. As compared with usual-care, the intervention group had greater improvements at intervention endpoint in dietary behavior, as measured by the FBC total score (20% increase in FBC total score, mean between-group difference, 8.7; 95% confidence interval, 5.7 to 11.7), and MEDAS total score (33% increase in MEDAS total score, mean between-group difference, 2.1; 95% CI 1.3 to 2.9). At 6 months after intervention, the intervention group also had greater improvements in both the FBC total score (15% increase) and MEDAS total score (25% increase), with mean between-group differences of 7.7 (CI 95%, 4.4 to 10.9) and 1.7 (CI 95%, 0.9 to 2.6), respectively. An eight-week interdisciplinary weight loss and lifestyle intervention resulted in meaningful and sustainable improvements in dietary behavior, including adherence to the Mediterranean diet in men who were overweight/ had obesity and CPAP-treated moderate-to-severe OSA.

Ketogenic diets, physical activity and body composition: a review

Obesity remains a serious relevant public health concern throughout the world despite related countermeasures being well understood (i.e. mainly physical activity and an adjusted diet). Among different nutritional approaches, there is a growing interest in ketogenic diets (KD) to manipulate body mass (BM) and to enhance fat mass loss. KD reduce the daily amount of carbohydrate intake drastically. This results in increased fatty acid utilisation, leading to an increase in blood ketone bodies (acetoacetate, 3-β-hydroxybutyrate and acetone) and therefore metabolic ketosis. For many years, nutritional intervention studies have focused on reducing dietary fat with little or conflicting positive results over the long term. Moreover, current nutritional guidelines for athletes propose carbohydrate-based diets to augment muscular adaptations. This review discusses the physiological basis of KD and their effects on BM reduction and body composition improvements in sedentary individuals combined with different types of exercise (resistance training or endurance training) in individuals with obesity and athletes. Ultimately, we discuss the strengths and the weaknesses of these nutritional interventions together with precautionary measures that should be observed in both individuals with obesity and athletic populations. A literature search from 1921 to April 2021 using Medline, Google Scholar, PubMed, Web of Science, Scopus and Sportdiscus Databases was used to identify relevant studies. In summary, based on the current evidence, KD are an efficient method to reduce BM and body fat in both individuals with obesity and athletes. However, these positive impacts are mainly because of the appetite suppressive effects of KD, which can decrease daily energy intake. Therefore, KD do not have any superior benefits to non-KD in BM and body fat loss in individuals with obesity and athletic populations in an isoenergetic situation. In sedentary individuals with obesity, it seems that fat-free mass (FFM) changes appear to be as great, if not greater, than decreases following a low-fat diet. In terms of lean mass, it seems that following a KD can cause FFM loss in resistance-trained individuals. In contrast, the FFM-preserving effects of KD are more efficient in endurance-trained compared with resistance-trained individuals.

A systematic review of inequalities in the uptake of, adherence to, and effectiveness of behavioral weight management interventions in adults

The extent to which behavioral weight management interventions affect health inequalities is uncertain, as is whether trials of these interventions directly consider inequalities. We conducted a systematic review, synthesizing evidence on how different aspects of inequality impact uptake, adherence, and effectiveness in trials of behavioral weight management interventions. We included (cluster-) randomized controlled trials of primary care-applicable behavioral weight management interventions in adults with overweight or obesity published prior to March 2020. Data about trial uptake, intervention adherence, attrition, and weight change by PROGRESS-Plus criteria (place of residence, race/ethnicity, occupation, gender, religion, education, socioeconomic status, social capital, plus other discriminating factors) were extracted. Data were synthesized narratively and summarized in harvest plots. We identified 91 behavioral weight loss interventions and 12 behavioral weight loss maintenance interventions. Fifty-six of the 103 trials considered inequalities in relation to at least one of intervention or trial uptake (n = 15), intervention adherence (n = 15), trial attrition (n = 32), or weight outcome (n = 34). Most trials found no inequalities gradient. If a gradient was observed for trial uptake, intervention adherence, and trial attrition, those considered "more advantaged" did best. Alternative methods of data synthesis that enable data to be pooled and increase statistical power may enhance understanding of inequalities in behavioral weight management interventions.

The 2D:4D index is associated with the development of excess body weight in adults, but not with the rate of weight loss following bariatric surgery

2D:4D finger length ratio is a proxy of prenatal sex hormone exposure. Prenatal testosterone decreases and prenatal estrogens increase this index. In the current study we investigated whether the 2D:4D index, as a marker of the prenatal hormonal environment, is associated with the development of overweight and obesity in adults, and whether is it correlated with the rate of weight loss in patients after bariatric surgery. We tested 125 adults with obesity (BMI ≥ 30.0 kg/m²), 125 adults with overweight (BMI 25.0–29.9 kg/m²) and 153 persons with normal body weight (BMI < 25 kg/m²) of both sexes. We have found that the development of excessive body weight in men and women, and fat accumulation in the upper arms, thighs and lower legs in women with obesity (but not men) are associated with increased prenatal estrogen exposure. This relationship indicates a new area of activity in the field of obesity prevention. Moreover, it seems that the 2D:4D index (especially of the right hand) may be a useful factor in early prediction of the risk of developing excessive body weight in humans. The rate of weight loss after bariatric surgery is independent of prenatal exposure to sex hormones.

Weight Cycling and Dieting Behavior in Fitness Club Members

Background

Along with the rising prevalence of high body-mass index (BMI), there is also increased emphasis on leanness and fitness. Both these trends suggest that many individuals are concerned about weight management and may try to lose weight. Using data from the research project "Fitness clubs - a venue for public health?", we aimed to describe weight cycling and energy-restricted dieting in men and women at start-up of fitness club membership, and to investigate influencing factors [age, BMI, educational level, self-classified overweight/obesity, compliance with nutritional guidelines, unhealthy weight control strategies and self-perceived health (SPH)].

Methods

In a cross-sectional online survey, 250 men and women from 25 fitness clubs in Oslo, reported anthropometrics, self-classified weight group, weight cycling, weight loss/gain, eating habits/dieting, and background/health information. Enrollment was limited to adult (≥18 years) novice exercisers (exercising <60 min/week at a moderate or vigorous intensity or brisk walking <150 min/week, the past six months) with less than four weeks of membership. Factors associated with weight cycling were examined using simple and multiple logistic regression, separated for men and women.

Results

In both sexes (mean age: 36.4 ± 11.3, range 18-71 years), a high number reported substantial weight fluctuation (+/-5 kg) the past 12 months (men: 50% and women: 62%, mean difference 12%, 95% CI -0.3 to 23.8, p=0.056) and unhealthy weight control strategies (men: 24.8% and women: 47.2%, mean difference 22.4%, 95% CI 10.5 to 33.4, p<0.001). Weight cyclers had a higher mean BMI compared with non-cyclers (mean difference -1.5, 95% CI -2.6 to - 0.4, p= 0.003). Further, the difference in body weight was 6.7 kg (95% CI 2.2 to 10.8, p=0.004) and 10.8 kg (95% CI 5.8 to 15.8, <0.001) in men and women, respectively. Besides BMI status, self-classified overweight/obesity was the strongest predictor of reporting weight cycling (men: OR 5.54, 95% CI 2.03 to 15.12, p<0.01 and women: OR 7.17, 95% CI 2.48 to 20.68, p<0.001).

Conclusion

In novice exercisers, a large proportion reported weight cycling and unhealthy weight control strategies, and both were more prevalent in women than in men. Self-classified overweight was found to be the most important factor influencing weight cycling.

Changes in food reward and intuitive eating after weight loss and maintenance in former athletes with overweight or obesity

OBJECTIVE

This study aimed to explore the following: 1) the impact of Champ4Life's intervention on intuitive eating and food reward; and 2) associations between changes in eating behavior and changes in body composition.

METHODS

A total of 94 former athletes (mean [SD], BMI = 31.1 [4.3] kg/m² , age = 43.0 [9.4] years, 34% female) assigned to intervention (n = 49) and control groups (n = 45) underwent 4 months of active weight loss (WL) followed by 8 months of WL maintenance. Intuitive eating and food reward were assessed by the Intuitive Eating Scale and the Leeds Food Preference Questionnaire, respectively.

RESULTS

The WL was -4.8% (4.9%) and 0.3% (2.6%) for the intervention and control groups, respectively. Participants reported a decrease in fat bias for explicit/implicit wanting and explicit liking after 4 months and 1 year. For intuitive eating, the unconditional permission to eat decreased after 4 months, and the body-food choice congruence increased after 1 year. Changes in unconditional permission to eat and in body-food choice congruence were positively and negatively associated with both Δweight and with Δfat mass, respectively. Changes in explicit wanting for fat and taste bias were associated with Δweight.

CONCLUSIONS

Food reward decreased after a moderate WL intervention. Participants successfully maintained their reduced weight, and most of the changes in eating behavior remained significant at the end of the follow-up period. Lifestyle interventions aiming at WL should also consider intuitive eating and food reward.

Calorie Restriction with or without Time-Restricted Eating in Weight Loss

BACKGROUND

The long-term efficacy and safety of time-restricted eating for weight loss are not clear.

METHODS

We randomly assigned 139 patients with obesity to time-restricted eating (eating only between 8:00 a.m. and 4:00 p.m.) with calorie restriction or daily calorie restriction alone. For 12 months, all the participants were instructed to follow a calorie-restricted diet that consisted of 1500 to 1800 kcal per day for men and 1200 to 1500 kcal per day for women. The primary outcome was the difference between the two groups in the change from baseline in body weight; secondary outcomes included changes in waist circumference, body-mass index (BMI), amount of body fat, and measures of metabolic risk factors.

RESULTS

Of the total 139 participants who underwent randomization, 118 (84.9%) completed the 12-month follow-up visit. The mean weight loss from baseline at 12 months was -8.0 kg (95% confidence interval [CI], -9.6 to -6.4) in the time-restriction group and -6.3 kg (95% CI, -7.8 to -4.7) in the daily-calorie-restriction group. Changes in weight were not significantly different in the two groups at the 12-month assessment (net difference, -1.8 kg; 95% CI, -4.0 to 0.4; P = 0.11). Results of analyses of waist circumferences, BMI, body fat, body lean mass, blood pressure, and metabolic risk factors were consistent with the results of the primary outcome. In addition, there were no substantial differences between the groups in the numbers of adverse events.

CONCLUSIONS

Among patients with obesity, a regimen of time-restricted eating was not more beneficial with regard to reduction in body weight, body fat, or metabolic risk factors than daily calorie restriction. (Funded by the National Key Research and Development Project [No. 2018YFA0800404] and others; ClinicalTrials.gov number, NCT03745612.).

PPAR-Targeted Therapies in the Treatment of Non-Alcoholic Fatty Liver Disease in Diabetic Patients

Peroxisome proliferator-activated receptors (PPAR), ligand-activated transcription factors of the nuclear hormone receptor superfamily, have been identified as key metabolic regulators in the liver, skeletal muscle, and adipose tissue, among others. As a leading cause of liver disease worldwide, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) cause a significant burden worldwide and therapeutic strategies are needed. This review provides an overview of the evidence on PPAR-targeted treatment of NAFLD and NASH in individuals with type 2 diabetes mellitus. We considered current evidence from clinical trials and observational studies as well as the impact of treatment on comorbid metabolic conditions such as obesity, dyslipidemia, and cardiovascular disease. Future areas of research, such as possible sexually dimorphic effects of PPAR-targeted therapies, are briefly reviewed.

Effect of an Interdisciplinary Weight Loss and Lifestyle Intervention on Obstructive Sleep Apnea Severity: The INTERAPNEA Randomized Clinical Trial

IMPORTANCE

Obesity is the leading cause of obstructive sleep apnea (OSA); however, the effects of weight loss and lifestyle interventions on OSA and comorbidities remain uncertain.

OBJECTIVE

To evaluate the effect of an interdisciplinary weight loss and lifestyle intervention on OSA and comorbidities among adults with moderate to severe OSA and overweight or obesity.

DESIGN, SETTING, AND PARTICIPANTS

The Interdisciplinary Weight Loss and Lifestyle Intervention for OSA (INTERAPNEA) study was a parallel-group open-label randomized clinical trial conducted at a hospital-based referral center in Granada, Spain, from April 1, 2019, to October 23, 2020. The study enrolled 89 Spanish men aged 18 to 65 years with moderate to severe OSA and a body mass index (calculated as weight in kilograms divided by height in meters squared) of 25 or greater who were receiving continuous positive airway pressure (CPAP) therapy. The sole inclusion of men was based on the higher incidence and prevalence of OSA in this population, the differences in OSA phenotypes between men and women, and the known effectiveness of weight loss interventions among men vs women.

INTERVENTIONS

Participants were randomized to receive usual care (CPAP therapy) or an 8-week weight loss and lifestyle intervention involving nutritional behavior change, aerobic exercise, sleep hygiene, and alcohol and tobacco cessation combined with usual care.

MAIN OUTCOMES AND MEASURES

The primary end point was the change in the apnea-hypopnea index (AHI) from baseline to the intervention end point (8 weeks) and 6 months after intervention. Secondary end points comprised changes in other OSA sleep-related outcomes, body weight and composition, cardiometabolic risk, and health-related quality of life.

RESULTS

Among 89 men (mean [SD] age, 54.1 [8.0] years; all of Spanish ethnicity; mean [SD] AHI, 41.3 [22.2] events/h), 49 were randomized to the control group and 40 were randomized to the intervention group. The intervention group had a greater decrease in AHI (51% reduction; change, -21.2 events/h; 95% CI, -25.4 to -16.9 events/h) than the control group (change, 2.5 events/h; 95% CI, -2.0 to 6.9 events/h) at the intervention end point, with a mean between-group difference of -23.6 events/h (95% CI, -28.7 to -18.5 events/h). At 6 months after intervention, the reduction in AHI was 57% in the intervention group, with a mean between-group difference of -23.8 events/h (95% CI, -28.3 to -19.3 events/h). In the intervention group, 18 of 40 participants (45.0%) no longer required CPAP therapy at the intervention end point, and 6 of 40 participants (15.0%) attained complete OSA remission. At 6 months after intervention, 21 of 34 participants (61.8%) no longer required CPAP therapy, and complete remission of OSA was attained by 10 of 34 participants (29.4%). In the intervention vs control group, greater improvements in body weight (change, -7.1 kg [95% CI, -8.6 to -5.5 kg] vs -0.3 kg [95% CI, -1.9 to 1.4 kg]) and composition (eg, change in fat mass, -2.9 kg [95% CI, -4.5 to -1.3 kg] vs 1.4 kg [95% CI, -0.3 to 3.1 kg]), cardiometabolic risk (eg, change in blood pressure, -6.5 mm Hg [95% CI, -10.3 to -2.6 mm Hg] vs 2.2 mm Hg [95% CI, -2.1 to 6.6 mm Hg]), and health-related quality of life (eg, change in Sleep Apnea Quality of Life Index, 0.8 points [95% CI, 0.5-1.1 points] vs 0.1 points [95% CI, -0.3 to 0.4 points]) were also found at the intervention end point.

CONCLUSIONS AND RELEVANCE

In this study, an interdisciplinary weight loss and lifestyle intervention involving Spanish men with moderate to severe OSA and had overweight or obesity and were receiving CPAP therapy resulted in clinically meaningful and sustainable improvements in OSA severity and comorbidities as well as health-related quality of life. This approach may therefore be considered as a central strategy to address the substantial impact of this increasingly common sleep-disordered breathing condition.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03851653.

Bridging the gap between science and society: long-term effects of the Healthy Lifestyle Community Programme (HLCP, cohort 1) on weight and the metabolic risk profile: a controlled study

Background

The potential of adopting a healthy lifestyle to fight non-communicable diseases (NCDs) is not fully used. We hypothesised that the Healthy Lifestyle Community Programme (HLCP, cohort 1) reduces weight and other risk markers compared with baseline and control.

Methods

24-month, non-randomised, controlled intervention trial. Intervention: intensive 8-week phase with seminars, workshops and coaching focusing on a healthy lifestyle (eg, plant-based diet, physical activity, stress management) and group support followed by a 22-month alumni phase. Weight reduction as the primary outcome and other NCD risk parameters were assessed at six time points. Participants were recruited from the general population. Multiple linear regression analyses were conducted.

Results

143 participants (58±12 years, 71% female) were enrolled (91 in the intervention (IG) and 52 in the control group (CG)). Groups’ baseline characteristics were comparable, except participants of IG were younger, more often females, overweight and reported lower energy intake (kcal/day). Weight significantly decreased in IG at all follow-ups by −1.5 ± 1.9 kg after 8 weeks to −1.9 ± 4.0 kg after 24 months and more than in CG (except after 24 months). Being male, in the IG or overweight at baseline and having a university degree predicted more weight loss. After the intervention, there were more participants in the IG with a ‘high’ adherence (+12%) to plant-based food patterns. The change of other risk parameters was most distinct after 8 weeks and in people at elevated risk. Diabetes-related risk parameters did not improve.

Conclusion

The HLCP was able to reduce weight and to improve aspects of the NCD risk profile. Weight loss in the IG was moderate but maintained for 24 months. Participants of lower educational status might benefit from even more practical units. Future interventions should aim to include more participants at higher risk.

Trial registration number

DRKS00018821.

Impact of training modes on fitness and body composition in women with obesity: A systematic review and meta-analysis

OBJECTIVE

This study aimed to assess the effectiveness of different exercise modalities and determine the optimal exercise prescription for improving cardiorespiratory fitness, body composition, and metabolic health of women with obesity.

METHODS

A systematic review of randomized controlled trials (RCTs) published between January 1988 and October 2020 was conducted. The RCTs were screened using the following inclusion criteria: 1) participants: women aged 18 to 65 years with BMI > 30 kg/m² and without comorbidities; 2) intervention: exercise; 3) comparison: non-intervention control; and 4) outcomes measures: cardiorespiratory fitness (maximal oxygen consumption), body composition (i.e., body weight, percentage body fat), and/or metabolic measures (i.e., blood pressure, cholesterol).

RESULTS

A total of 20 RCTs with a total of 2,062 participants were included. Although the results showed that any form of exercise was more effective than control, improvements in fitness and body composition were modest. Aerobic exercise (vigorous and moderate intensity) appeared most promising for improving fitness and body weight, whereas low-load resistance training resulted in the largest improvements in body fatness.

CONCLUSIONS

In women living with obesity, aerobic exercise was consistently effective in improving fitness and body composition. Although both resistance training and combined exercise interventions appear promising, more research is needed to evaluate their efficacy and determine an optimal exercise prescription for this population.

Effect of oral contraceptives on energy balance in women: A review of current knowledge and potential cellular mechanisms

Body weight management is currently of major concern as the obesity epidemic is still a worldwide challenge. As women face more difficulties to lose weight than men, there is an urgent need to better understand the underlying reasons and mechanisms. Recent data have suggested that the use of oral contraceptive (OC) could be involved. The necessity of utilization and development of contraceptive strategies for birth regulation is undeniable and contraceptive pills appear as a quite easy approach. Moreover, OC also represent a strategy for the management of premenstrual symptoms, acne or bulimia nervosa. The exact impact of OC on body weight remains not clearly established. Thus, after exploring the potential underlying mechanisms by which OC could influence the two side of energy balance, we then provide an overview of the available evidence regarding the effects of OC on energy balance (i.e. energy expenditure and energy intake). Finally, we highlight the necessity for future research to clarify the cellular effects of OC and how the individualization of OC prescriptions can improve long-term weight loss management.

Exploring Obesity as a Gendered Contagion: Impact on Lifestyle Interventions to Improve Cardiovascular Health

PURPOSE

Obesity increases the risk of cardiovascular disease. Lifestyle interventions such as physical activity and diet are important components for reducing the risk of obesity. Data suggest that lifestyle choices differ between men and women, as well as in groups. The purpose of this review was to explore whether obesity can be considered as a gendered social contagion, associated with differences in lifestyle and response to lifestyle interventions in men and women.

FINDINGS

There are important sex-based differences of obesity to consider. There is evidence that peers have an influence on lifestyle preferences such as physical activity level and dietary habits, but the evidence is inconclusive if the differences exist between men and women. Similarly, data from lifestyle intervention studies are not conclusive whether there are differences between men and women. There is not enough evidence for the notion that obesity is a gendered social contagion.

IMPLICATIONS

More research is needed to understand differences in lifestyle and lifestyle interventions between men and women, especially across the life span, which could have profound public health implications.

Sex/Gender Differences in Obesity Prevalence, Comorbidities, and Treatment

PURPOSE OF REVIEW

Obesity is a heterogeneous condition, yet sex/gender is rarely considered in the prevention or clinical care of this disease. This review examined and evaluated recent literature regarding the influence of sex and gender on obesity prevalence, comorbidities, and treatment in adults.

RECENT FINDINGS

Obesity is more prevalent in women than men in most countries, but in some countries and population subgroups, this gap is more pronounced. Several obesity-related comorbidities, including type 2 diabetes and hypertension, demonstrate sex-specific pathways. Women, compared to men, are more likely to be diagnosed with obesity and seek and obtain all types of obesity treatment including behavioral, pharmacological, and bariatric surgery. Men tend to have greater absolute weight loss, but this difference is attenuated once accounting for baseline weight. Obesity is a multifactorial condition with complex interactions among sex/gender, sociocultural, environmental, and physiological factors. More sex/gender research is needed to investigate mechanisms underlying sex/gender differences in prevalence, comorbidities, and treatment, identify ways to increase men's interest and participation in obesity treatment, and examine differences in obesity prevalence and treatments for transgender and gender non-conforming individuals.

Microvessel Density: Integrating Sex-Based Differences and Elevated Cardiovascular Risks in Metabolic Syndrome

Metabolic syndrome (MetS) is a complex pathological state consisting of metabolic risk factors such as hypertension, insulin resistance, and obesity. The interconnectivity of cellular pathways within various biological systems suggests that each individual component of MetS may share common pathological sources. Additionally, MetS is closely associated with vasculopathy, including a reduction in microvessel density (MVD) (rarefaction) and elevated risk for various cardiovascular diseases. Microvascular impairments may contribute to perfusion-demand mismatch, where local metabolic needs are insufficiently met due to the lack of nutrient and oxygen supply, thus creating pathological positive-feedback loops and furthering the progression of disease. Sexual dimorphism is evident in these underlying cellular mechanisms, which places males and females at different levels of risk for cardiovascular disease and acute ischemic events. Estrogen exhibits protective effects on the endothelium of pre-menopausal women, while androgens may be antagonistic to cardiovascular health. This review examines MetS and its influences on MVD, as well as sex differences relating to the components of MetS and cardiovascular risk profiles. Finally, translational relevance and interventions are discussed in the context of these sex-based differences.

Weight Loss Interventions for Hispanic Women in the United States: A Systematic Review

Background

Obesity rates in Hispanic women residing in the United States (U.S.) are disproportionately high, increasing the risk of obesity-related disease and mortality. The effectiveness of interventions targeting weight loss in this population remains largely unknown.

Purpose

The purpose of this review was to systematically evaluate the evidence related to the effectiveness of weight loss interventions conducted among U.S. Hispanic women and provide guidance for future research.

Methods

Bibliographic databases (n = 10, from each database's inception to July 2, 2019) were searched using the PRISMA guidelines for systematic reviews. Randomized controlled trials (RCTs) and quasi-experimental studies with weight change outcomes were included. Results were described in a narrative synthesis.

Results

5,423 articles were assessed for eligibility based on inclusion criteria; 15 studies were included in the final review. Nine trials were RCTs and six were quasi-experimental studies; all but six were pilot studies. Most studies recruited overweight or obese women with no existing medical conditions and did not follow participants beyond the intervention. All trials were delivered in-person. Intervention strategies and content and weight change outcomes were highly variable.

Conclusions

RCTs with statistically powered sample sizes are needed to robustly test the effects of weight loss interventions in this population.

Very-low-calorie ketogenic diet: An alternative to a pharmacological approach to improve glycometabolic and gonadal profile in men with obesity

Obesity and metabolic diseases have become a worrying reality, especially in more developed societies. They are associated with the development of many comorbidities, such as type 2 diabetes mellitus, hypogonadism, hypertension, cerebrovascular and cardiovascular diseases, neoplasia, obstructive sleep apnea, and non-alcoholic fatty liver disease. Therefore, weight loss is of paramount importance. A promising therapeutic option to achieve this goal is the very-low-calorie ketogenic diet. This review aims to summarize the main effects of very-low-calorie-ketogenic diet on the glycometabolic and gonadal profiles of men with overweight/obesity.