Dieting and weight cycling as risk factors for cardiometabolic diseases: who is really at risk?

Weight stigma is uniquely tied to maladaptive eating across different racial, ethnic, and gender groups

Weight stigma, racism, and sexism (social devaluation due to body weight, race or ethnicity, and sex or gender), have been linked to increased maladaptive eating behaviors; however, no research has investigated the unique associations between different forms of stigma and eating concurrently. We analyzed within-group (by race/ethnicity and sex) effects of different forms of stigma on maladaptive eating behaviors to test whether there is some unique relationship between weight stigma and maladaptive eating across identities. Additionally, we explored differences by racial/ethnic group and sex, as well as BMI category, in levels of reported weight stigma, racism, sexism, and maladaptive eating. Participants (N = 1051) were recruited so that there were approximately even numbers of participants identifying as Black (33.3%), Hispanic or Latino (32.8%), and White (33.9%). Overall, participants reported similar amounts of weight stigma by race/ethnicity and sex, but different levels of racism and sexism. Weight stigma, but not racism or sexism consistently predicted binge eating and eating to cope across groups, controlling for education, income, BMI, and age. Restricted dieting, however, was only predicted by weight stigma for Hispanic/Latino and Black men. These findings suggest that weight stigma is a unique predictor of maladaptive eating, even when considering the effects of racism and sexism. This study provides evidence of a more focused model of weight stigma and eating outcomes, rather than a more general model of the effect of stigma on eating outcomes due to overall stress. Future research should investigate when and why weight stigma drives restricted dieting, since this relationship seems strongest in men, going against many common inclinations about weight stigma.

Are anti-gravity treadmills reliable to explore exercise energy metabolism at low degrees of alleviation in normal-weight male individuals?

BACKGROUND

Exploring the independent effect of mechanical discharge in response to weight loss (WL) seems necessary but remains highly challenging from a methodological point. Anti-gravity treadmills could be relevant to simulate a mechanical WL by body weight support (BWS), but their reliability remains unclear to properly explore exercise energy metabolism, especially at low degrees of alleviations.

OBJECTIVE

The study aimed to evaluate the accuracy and reproducibility of an anti-gravity treadmill to generate BWS, and the reproducibility of cardiometabolic responses to an exercise performed at low degrees of BWS on this device.

METHODS

Observed BWS of 18 normal-weight males was obtained twice at seven degrees of target BWS (i.e., 0, 3, 6, 9, 12, 15, 18%) using a digital scale inside the anti-gravity treadmill, and was compared to the expected BWS. Then, 15 of them performed 5-min bout of low-intensity walking exercise at these degrees of BWS in a randomized order, separated by 4-min rest. The exercise was identically repeated on three occasions separated by a minimum of 3 days. Energy metabolism and heart rate (HR) were measured throughout the exercise by indirect calorimetry and a HR monitor, respectively.

RESULTS

The observed BWS were significantly different from the expected BWS (p< 0.001), and there was a high inter- and intra-individual variability in BWS generated by the anti-gravity treadmill. Results showed an overall good reliability of VO2 (intraclass correlation coefficients (ICC) values ranging from 0.67 to 0.85) and HR (ICC > 0.8) in response to exercise. An effect of the degree of BWS was observed for VO2 (p< 0.001), illustrating reduced values at 15% and 18% of BWS compared to 0, 3, and 6%.

CONCLUSIONS

Such device might not be adapted to simulate low degrees of WL in normal-weight males, particularly when it comes to the exploration of energy metabolism.

US Navy Sailors Modify Their Eating Behaviors to Pass Cyclic Physical Readiness Tests

OBJECTIVE

Investigate the influence of physical readiness tests (PRTs) on eating behaviors among US Navy Sailors.

DESIGN

Focused ethnography using interviews and military policies.

SETTING

Three US Naval installations.

PARTICIPANTS

Active-duty enlisted Sailors (n = 32).

PHENOMENON OF INTEREST

Eating behaviors.

ANALYSIS

Authors analyzed data iteratively with data collection using domain, taxonomy, and thematic analysis to identify culturally relevant codes, domains, and themes.

RESULTS

Five themes corresponded with PRT timing and Sailors' perceived ability to meet standards: (1) maintain usual eating habits, (2) get ready and switch it up, (3) make weight-damage control, (4) return to baseline-PRT is over, and (5) eat whatever-PRT is canceled. In contrast to the PRT policy's goal for Sailors to maintain standards and a healthy lifestyle, many Sailors modified their usual eating behaviors to pass the test.

CONCLUSION AND IMPLICATIONS

Changes in eating behaviors during PRT cycles highlight a culture of getting ready vs staying ready, suggesting many Sailors do not eat a nutrient-dense diet to maintain the minimum physical fitness and body composition standards. There is a need for nutrition education for healthy weight maintenance, weight gain prevention, and healthy weight loss among military personnel.

Body Mass Index Trends for the Top Five Finishers in Men's Grand Tour and Monument Cycling Events from 1994-2023: Implications for Athletes and Sporting Stakeholders

Weight-related issues can be prevalent in elite-level sports, especially in men's road cycling, where riders may exhibit harmful behaviours, with potentially adverse outcomes for mental and physical health. This study investigated Body Mass Index (BMI) values amongst the top five finishers in the three Grand Tours and the five Monuments races between 1994 and 2023 to assess longitudinal patterns. Publicly available height and weight figures were sourced from ProCyclingStats and BMI scores were calculated for n = 154 and n = 255 individual athletes for the Grand Tours and Monuments, respectively. Two analyses were conducted with correlations and ANOVAs: the first included the BMIs of all top-five finishes and the second focussed on the BMIs of new top-five entrants. The results from both analyses revealed consistent mean BMI decreases over the years and larger effect sizes were apparent in the Grand Tours compared to the Monuments. Although lower BMIs are associated with certain performance advantages, these declining trajectories suggest a need for enhanced awareness in the cycling community and possible regulatory measures and educational programmes to promote the sustainable wellbeing of riders. This may be particularly pertinent given the wider evidence of unhealthy weight-related attitudes and behaviours throughout the sport.

The Impact of Weight Cycling on Health and Obesity

Obesity is a systemic and chronic inflammation, which seriously endangers people's health. People tend to diet to control weight, and the short-term effect of dieting in losing weight is significant, but the prognosis is limited. With weight loss and recovery occurring frequently, people focus on weight cycling. The effect of weight cycling on a certain tissue of the body also has different conclusions. Therefore, this article systematically reviews the effects of body weight cycling on the body and finds that multiple weight cycling (1) increased fat deposition in central areas, lean mass decreased in weight loss period, and fat mass increased in weight recovery period, which harms body composition and skeletal muscle mass; (2) enhanced the inflammatory response of adipose tissue, macrophages infiltrated into adipose tissue, and increased the production of pro-inflammatory mediators in adipocytes; (3) blood glucose concentration mutation and hyperinsulinemia caused the increase or decrease in pancreatic β-cell population, which makes β-cell fatigue and leads to β-cell failure; (4) resulted in additional burden on the cardiovascular system because of cardiovascular rick escalation. Physical activity combined with calorie restriction can effectively reduce metabolic disease and chronic inflammation, alleviating the adverse effects of weight cycling on the body.

Association of body mass index and blood pressure variability with 10-year mortality and renal disease progression in type 2 diabetes

BACKGROUND

Variability in biological parameters may be associated with adverse outcomes. The aim of the study was to determine whether variability in body mass index (BMI) and blood pressure is associated with all-cause, cardiovascular mortality and cancer mortality or with renal disease progression in subjects with type 2 diabetes.

METHODS

The diabetes database was accessed, and all the information on patient visits (consultations) carried out in the study period (1 January 2008-31 December 2019) was extracted and linked to the laboratory database and the mortality register.

RESULTS

The total number of patients included in the study population was 26,261, of whom 54.4% were male. Median (interquartile range, IQR) age was 60.2 (51.8-68.3) years. The coefficient of variability of BMI was independently associated with increased all-cause and cardiovascular, but not cancer, mortality. Glycated haemoglobin (HbA1c) was associated with increased all-cause, cardiovascular, and cancer mortality as well as with renal progression. Variability in systolic blood pressure, diastolic blood pressure, and pulse pressure was associated with increased all-cause and cardiovascular mortality in bivariate, but not in multivariate, analyses.

CONCLUSIONS

Variability in BMI was associated with increased all-cause and cardiovascular, but not cancer, mortality in a large real-world contemporary population. Our results also confirm the association of HbA1c with increased all-cause, cardiovascular, and cancer mortality as well as with renal progression.

Challenges in identifying malnutrition in obesity; An overview of the state of the art and directions for future research

(Protein-energy) malnutrition in individuals living with obesity presents complex diagnostic challenges due to the distinctive physiological characteristics of obesity. This narrative review critically examines the identification of malnutrition within the population with obesity, distinguishing malnutrition in obesity from related conditions such as sarcopenic obesity. While noting some shared features, the review highlights key differences between these conditions. The review also highlights the limitations of current malnutrition screening tools, which are not designed for individuals living with obesity. These tools primarily rely on anthropometric measurements, neglecting (among others) nutrient intake assessment, which hinders accurate malnutrition detection. Additionally, this review discusses limitations in existing diagnostic criteria, including the Global Leadership Initiative on Malnutrition (GLIM) criteria, when applied to individuals living with obesity. Challenges include the identification of appropriate cut-off values for phenotypic criteria (unintentional weight loss, low body mass index and muscle mass) and aetiological criteria such as reduced food intake and inflammation for the population with obesity. Overall, this review emphasises the need for modified screening tools and diagnostic criteria to recognise and assess malnutrition in obesity, leading to improved clinical outcomes and overall wellbeing.

The association between patterns of weight change, diabetes status and glycaemia among adults with overweight and obesity

AIMS

To investigate the associations between weight change patterns and 5-year incident non-diabetic hyperglycaemia (NDH), and glycated haemoglobin (HbA1c) levels among individuals who had overweight or obesity.

METHODS

This longitudinal cohort study (N = 435) pooled data from a weight management trial. Participants were adults with a body mass index of ≥28 kg/m2. They were categorised as "no weight loss", "maintainers", and "regainers" based on their weight at 3 months and 12 months after baseline. Multivariable logistic regression models and linear regressions were conducted to examine the associations.

RESULTS

Between 1-year and 5-year follow-ups, 77 participants developed NDH. We found no statistically significant association between weight change patterns and incident NDH at 5 years. Among weight loss maintainers, mean HbA1c was -0.15% (95% confidence intervals (CI): -0.22, -0.10) lower after 1 year and -0.15% (95% CI: -0.23, -0.06) lower after 5 years compared to the no weight loss group. There was no difference between weight loss regainers and no weight loss group in HbA1c levels.

CONCLUSIONS

Compared to those who did not lose weight, participants who maintained their weight loss had lower HbA1c levels after 1 year and 5 years, which highlights the importance of providing long-term support to prevent weight regain.

The association of long-term trajectories of BMI, its variability, and metabolic syndrome: a 30-year prospective cohort study

Background

Limited data exists on how early-life weight changes relate to metabolic syndrome (MetS) risk in midlife. This study examines the association between long-term trajectories of body mass index (BMI), its variability, and MetS risk in Chinese individuals.

Methods

In the Hanzhong Adolescent Hypertension study (March 10, 1987-June 3, 2017), 1824 participants with at least five BMI measurements from 1987 to 2017 were included. Using group-based trajectory modeling, different BMI trajectories were identified. BMI variability was assessed through standard deviation (SD), variability independent of the mean (VIM), and average real variability (ARV). Logistic regression analyzed the relationship between BMI trajectory, BMI variability, and MetS occurrence in midlife (URL: https://www.clinicaltrials.gov; Unique identifier: NCT02734472).

Findings

BMI trajectories were categorized as low-increasing (34.4%), moderate-increasing (51.8%), and high-increasing (13.8%). Compared to the low-increasing group, the odds ratios (ORs) [95% CIs] for MetS were significantly higher in moderate (4.27 [2.63-6.91]) and high-increasing groups (13.11 [6.30-27.31]) in fully adjusted models. Additionally, higher BMI variabilities were associated with increased MetS odds (ORs for SDBMI, VIMBMI, and ARVBMI: 2.30 [2.02-2.62], 1.22 [1.19-1.26], and 4.29 [3.38-5.45]). Furthermore, BMI trajectories from childhood to adolescence were predictive of midlife MetS, with ORs in moderate (1.49 [1.00-2.23]) and high-increasing groups (2.45 [1.22-4.91]). Lastly, elevated BMI variability in this period was also linked to higher MetS odds (ORs for SDBMI, VIMBMI, and ARVBMI: 1.24 [1.08-1.42], 1.00 [1.00-1.01], and 1.21 [1.05-1.38]).

Interpretation

Our study suggests that both early-life BMI trajectories and BMI variability could be predictive of incident MetS in midlife.

Funding

This work was supported by the National Natural Science Foundation of China No. 82070437 (J.-J.M.), the Clinical Research Award of the First Affiliated Hospital of Xi'an Jiaotong University of China (No. XJTU1AF-CRF-2022-002, XJTU1AF2021CRF-021, and XJTU1AF-CRF-2023-004), the Key R&D Projects in Shaanxi Province (Grant No. 2023-ZDLSF-50), the Chinese Academy of Medical Sciences & Peking Union Medical College (2017-CXGC03-2), and the International Joint Research Centre for Cardiovascular Precision Medicine of Shaanxi Province (2020GHJD-14).

Mobile health (m-health) smartphone interventions for adolescents and adults with overweight or obesity

BACKGROUND

Obesity is considered to be a risk factor for various diseases, and its incidence has tripled worldwide since 1975. In addition to potentially being at risk for adverse health outcomes, people with overweight or obesity are often stigmatised. Behaviour change interventions are increasingly delivered as mobile health (m-health) interventions, using smartphone apps and wearables. They are believed to support healthy behaviours at the individual level in a low-threshold manner.

OBJECTIVES

To assess the effects of integrated smartphone applications for adolescents and adults with overweight or obesity.

SEARCH METHODS

We searched CENTRAL, MEDLINE, PsycINFO, CINAHL, and LILACS, as well as the trials registers ClinicalTrials.gov and World Health Organization International Clinical Trials Registry Platform on 2 October 2023 (date of last search for all databases). We placed no restrictions on the language of publication.

SELECTION CRITERIA

Participants were adolescents and adults with overweight or obesity. Eligible interventions were integrated smartphone apps using at least two behaviour change techniques. The intervention could target physical activity, cardiorespiratory fitness, weight loss, healthy diet, or self-efficacy. Comparators included no or minimal intervention (NMI), a different smartphone app, personal coaching, or usual care. Eligible studies were randomised controlled trials of any duration with a follow-up of at least three months.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology and the RoB 2 tool. Important outcomes were physical activity, body mass index (BMI) and weight, health-related quality of life, self-efficacy, well-being, change in dietary behaviour, and adverse events. We focused on presenting studies with medium- (6 to < 12 months) and long-term (≥ 12 months) outcomes in our summary of findings table, following recommendations in the core outcome set for behavioural weight management interventions.

MAIN RESULTS

We included 18 studies with 2703 participants. Interventions lasted from 2 to 24 months. The mean BMI in adults ranged from 27 to 50, and the median BMI z-score in adolescents ranged from 2.2 to 2.5. Smartphone app versus no or minimal intervention Thirteen studies compared a smartphone app versus NMI in adults; no studies were available for adolescents. The comparator comprised minimal health advice, handouts, food diaries, smartphone apps unrelated to weight loss, and waiting list. Measures of physical activity: at 12 months' follow-up, a smartphone app compared to NMI probably reduces moderate to vigorous physical activity (MVPA) slightly (mean difference (MD) -28.9 min/week (95% confidence interval (CI) -85.9 to 28; 1 study, 650 participants; moderate-certainty evidence)). We are very uncertain about the results of estimated energy expenditure and cardiorespiratory fitness at eight months' follow-up. A smartphone app compared with NMI probably results in little to no difference in changes in total activity time at 12 months' follow-up and leisure time physical activity at 24 months' follow-up. Anthropometric measures: a smartphone app compared with NMI may reduce BMI (MD of BMI change -2.6 kg/m2, 95% CI -6 to 0.8; 2 studies, 146 participants; very low-certainty evidence) at six to eight months' follow-up, but the evidence is very uncertain. At 12 months' follow-up, a smartphone app probably resulted in little to no difference in BMI change (MD -0.1 kg/m2, 95% CI -0.4 to 0.3; 1 study; 650 participants; moderate-certainty evidence). A smartphone app compared with NMI may result in little to no difference in body weight change (MD -2.5 kg, 95% CI -6.8 to 1.7; 3 studies, 1044 participants; low-certainty evidence) at 12 months' follow-up. At 24 months' follow-up, a smartphone app probably resulted in little to no difference in body weight change (MD 0.7 kg, 95% CI -1.2 to 2.6; 1 study, 245 participants; moderate-certainty evidence). A smartphone app compared with NMI may result in little to no difference in self-efficacy for a physical activity score at eight months' follow-up, but the results are very uncertain. A smartphone app probably results in little to no difference in quality of life and well-being at 12 months (moderate-certainty evidence) and in little to no difference in various measures used to inform dietary behaviour at 12 and 24 months' follow-up. We are very uncertain about adverse events, which were only reported narratively in two studies (very low-certainty evidence). Smartphone app versus another smartphone app Two studies compared different versions of the same app in adults, showing no or minimal differences in outcomes. One study in adults compared two different apps (calorie counting versus ketogenic diet) and suggested a slight reduction in body weight at six months in favour of the ketogenic diet app. No studies were available for adolescents. Smartphone app versus personal coaching Only one study compared a smartphone app with personal coaching in adults, presenting data at three months. Two studies compared these interventions in adolescents. A smartphone app resulted in little to no difference in BMI z-score compared to personal coaching at six months' follow-up (MD 0, 95% CI -0.2 to 0.2; 1 study; 107 participants). Smartphone app versus usual care Only one study compared an app with usual care in adults but only reported data at three months on participant satisfaction. No studies were available for adolescents. We identified 34 ongoing studies.

AUTHORS' CONCLUSIONS

The available evidence is limited and does not demonstrate a clear benefit of smartphone applications as interventions for adolescents or adults with overweight or obesity. While the number of studies is growing, the evidence remains incomplete due to the high variability of the apps' features, content and components, which complicates direct comparisons and assessment of their effectiveness. Comparisons with either no or minimal intervention or personal coaching show minor effects, which are mostly not clinically significant. Minimal data for adolescents also warrants further research. Evidence is also scarce for low- and middle-income countries as well as for people with different socio-economic and cultural backgrounds. The 34 ongoing studies suggest sustained interest in the topic, with new evidence expected to emerge within the next two years. In practice, clinicians and healthcare practitioners should carefully consider the potential benefits, limitations, and evolving research when recommending smartphone apps to adolescents and adults with overweight or obesity.

Associations between adverse childhood experiences and history of weight cycling

Background

Adverse childhood experiences (ACEs) predict obesity onset; however, the relationship between ACEs and history of weight cycling has not been adequately explored. This gap is problematic given the difficulty in weight loss maintenance and the impact of ACEs on obesity development, chronicity, and associated weight stigma. The objective of this study was to examine associations between self-reported history of ACEs and weight cycling in a sample of weight loss treatment-seeking adults with overweight/obesity.

Methods

The number of participants in the analyzed sample was 78, mostly white educated adult women (80% female, 81% Caucasian, 75% ≥ bachelor's degree) with excess adiposity enrolled in the Cognitive and Self-regulatory Mechanisms of Obesity Study. ACEs were measured at baseline using the ACEs Scale. History of weight cycling was measured using the Weight and Lifestyle Inventory that documented weight loss(es) of 10 or more pounds.

Results

Higher ACE scores were associated with a greater likelihood of reporting a history of weight cycling. Participants with four or more ACEs had 8 times higher odds (OR = 8.301, 95% CI = 2.271-54.209, p = 0.027) of reporting weight cycling compared with participants with no ACEs. The association of weight cycling for those who endorsed one to three ACEs was not significant (OR = 2.3, 95% CI = 0.771-6.857, p = 0.135) in this sample.

Conclusions

The role of ACEs in health may be related to associations with weight cycling. Results indicated that those who reported four or more ACEs had significantly higher odds of reporting weight cycling compared with those with no ACEs. Further research is needed to further explore how ACEs predict the likelihood of weight cycling, which may be prognostic for sustained weight loss treatment response and weight stigma impacts.

Weight Loss Attempts Increased in Korean Adults from 2005 to 2021, Excluding Those with Obesity

Background: Studies on trends in the proportions of past-year weight loss attempts among Asian adults are limited. Our hypotheses were that trends in the proportions would increase and sociodemographic, weight, and health-related factors would be associated with these attempts. Methods: Using data from the Korea National Health and Nutrition Examination Survey 2005-2021, this study evaluated the trends and their related factors among Korean adults. Complex sample design analyses were applied to the data of 80,160 adults. Results: The weighted proportion of past-year weight loss attempts increased from 35.2% in 2005 to 41.3% in 2021. The proportion of past-year weight loss attempts increased for individuals with nonobese body mass index (BMIs) (<25 kg/m2), decreased for males with obese BMIs (≥25 kg/m2), and did not change for females with obese BMIs. A multivariate-adjusted model showed that the proportion of weight loss attempts decreased for males and increased for females over the 16-year period [odds ratio (OR) (95% confidence interval): males, 0.993 (0.988-0.998); females, 1.013 (1.009-1.017)]. The OR of weight loss attempts was higher for females, younger individuals, and those with higher economic status, higher BMIs, self-perceived larger body shapes, self-rated better health, and chronic diseases. These characteristics decreased the odds of individuals with obese BMIs making no weight loss attempts. Conclusions: The proportion of past-year weight loss attempts increased over the 16-year period among all participants, but a declining trend was observed for those with obesity. In addition to BMI, socioeconomic factors, subjective perceptions of body shape, and health-related factors were related to weight loss attempts.

Weight regain, body composition, and metabolic responses to weight loss in weight cycling athletes: A systematic review and meta-analyses

Depending on the nature of their sports, athletes may be engaged in successive weight loss (WL) and regain, conducing to "weight cycling." The aims of this paper were to systematically (and meta-analytically when possible) analyze the post-WL recovery of (i) body weight and (ii) fat mass; fat-free mass; and performance and metabolic responses in weight cycling athletes (18-55 years old, body mass index < 30 kg.m-2 ). MEDLINE, Embase, and SPORTDiscus databases were explored. The quality and risk of bias of the 74 included studies were assessed using the quality assessment tool for quantitative studies. Thirty-two studies were eligible for meta-analyses. Whatever the type of sports or methods used to lose weight, post-WL body weight does not seem affected compared with pre-WL. While similar results are observed for fat-free mass, strength sports athletes (also having longer WL and regain periods) do not seem to fully recover their initial fat mass (ES: -0.39, 95% CI: [-0.77; -0.00], p = 0.048, I2  = 0.0%). Although the methods used by athletes to achieve WL might prevent them from a potential post-WL fat overshooting, further studies are needed to better understand WL episodes consequences on athletes' performance as well as short- and long-term physical, metabolic, and mental health.

Finding kindness: A randomized controlled trial of an online self-compassion intervention for weight management (SC4WM)

INTRODUCTION

Weight loss is hard to achieve and even harder to maintain. Engaging in effortful behavioural change to manage body weight can sometimes result in feelings of guilt and shame. Self-compassion, the tendency to find kindness for oneself in times of struggle, may facilitate coping with the unique challenges of weight management. This study assessed whether a remotely delivered self-compassion intervention improved weight management outcomes when delivered as a supplement to an existing digital behavioural weight management programme, Weight Watchers (WW).

METHOD

Using a mixed-method study design, 249 adults seeking to manage weight were randomized to either the WW programme or WW supplemented with the self-compassion for weight management intervention (SC4WM). Participants completed measures of self-compassion, eating behaviour, physical activity, body weight and emotional well-being along with potential moderators, including weight self-stigma, eating restraint, psychological coping and perceived stress at baseline, post-intervention (4 weeks) and follow-up (12 weeks).

RESULTS

There was no evidence that the SC4WM intervention had a significantly different effect than WW alone. Other than body weight, all outcomes improved over time in both groups. Self-compassion was slightly higher overall in the SC4WM group (p = .05), with this group reporting higher self-kindness at 4 weeks (p = .014) and lower self-judgement at 12 weeks (p = .023) compared to the control group.

CONCLUSIONS

Although the SC4WM intervention group did show a small increase in self-kindness and reduction in self-judgement, weight management outcomes were not improved over and above the existing WW programme. Recommendations for adapting the SC4WM intervention to improve efficacy to augment weight management outcomes are provided.

Physiological Perturbations in Combat Sports: Weight Cycling and Metabolic Function-A Narrative Review

Combat sports athletes seeking a competitive edge often engage in weight management practices to become larger than their opponents, which ultimately includes periods of gradual weight loss, rapid weight loss, and weight regain. This pattern of weight loss and regain is known as weight cycling and often includes periods of low energy availability, making combat sports athletes susceptible to metabolic dysfunction. This narrative review represents an effort to explore the metabolic perturbations associated with weight cycling and outline the short-, medium-, and long-term effects on metabolic flexibility, function, and health. The short-term effects of rapid weight loss, such as a reduced metabolic rate and alterations to insulin and leptin levels, may prelude the more pronounced metabolic disturbances that occur during weight regain, such as insulin resistance. Although definitive support is not currently available, this cycle of weight loss and regain and associated metabolic changes may contribute to metabolic syndrome or other metabolic dysfunctions over time.

Single cell RNA-sequencing suggests a novel lipid associated mast cell population following weight cycling

Our recent study showed weight cycled mice have increased adipose mast cells compared to obese mice by single cell RNA-sequencing. Here, we aimed to confirm and elucidate these changes. Further analysis of our dataset showed that our initial mast cell cluster could subcluster into two unique populations: one with very high expression of classical mast cell markers and another with elevated lipid handling and antigen presentation genes. This new mast cell cluster accounted for most of the mast cells in the weight cycled group although it was not possible to detect the different populations by new studies with flow cytometry or Toluidine blue staining in mice, possibly due to a downregulation in classical mast cell genes. Interestingly, a pilot study in humans did suggest the existence of two mast cell populations in subcutaneous adipose tissue from obese women that appear similar to the murine populations detected by sequencing; one of which was significantly correlated with weight variance. Together, these data suggest that weight cycling may induce a unique population of mast cells similar to lipid associated macrophages. Future studies will focus on isolation of these cells to better determine their lineage, differentiation, and functional roles.

Effects of body weight variability on risks of macro- and microvascular outcomes in individuals with type 2 diabetes: The Rio de Janeiro type 2 diabetes cohort

AIMS

To investigate the effects of body weight variability (BWV) on macro- and microvascular outcomes in a type 2 diabetes cohort.

METHODS

BWV parameters were assessed in 684 individuals. Multivariable Cox regressions examined associations between BWV parameters and cardiovascular outcomes (total cardiovascular events [CVEs], major CVEs [MACEs], cardiovascular deaths),all-cause mortality and microvascular outcomes. Interaction/subgroup analyses were performed according to being physically-active/sedentary and having/not lost ≥ 5 % of weight.

RESULTS

Median follow-up was 11 years over which 194 total CVEs (174 MACEs), and 223 all-cause deaths (110 cardiovascular), occurred. There were 215 renal, 152 retinopathy and 167 peripheral neuropathy development/worsening outcomes. In general, increased BWV was associated with higher risks of CVEs, MACEs, all-cause mortality, advanced renal failure and peripheral neuropathy outcomes, but not of microalbuminuria and retinopathy outcomes. On interaction/subgroup analyses, increased BWV was associated with higher risks of outcomes in sedentary individuals and in those who did not lose ≥ 5 % of body weight. In physically-active participants or in those who lost ≥ 5 % weight, the adjusted risks were null or protective.

CONCLUSIONS

Increased BWV was associated with most adverse outcomes; however, in those who were physically-active or consistently losing weight, it was not hazardous and might be even beneficial.

Is dieting a risk for higher weight gain in normal-weight individual? A systematic review and meta-analysis

While there is an increasing prevalence of dieting in the overall population, weight loss (WL) practices could be a risk factor for weight gain (WG) in normal-weight (NW) individuals. The aim of the present work was to systematically review all the studies implicating diet restriction and body weight (BW) evolution in NW people. The literature search was registered in PROSPERO (CRD42021281442) and was performed in three databases from April 2021 to June 2022 for articles involving healthy NW adults. From a total of 1487 records initially identified, eighteen were selected in the systematic review. Of the eight dieting interventional studies, only one found a higher BW after weight recovery, but 75 % of them highlighted metabolic adaptations in response to WL favouring weight regain and persisting during/after BW recovery. Eight of the ten observational studies showed a relationship between dieting and major later WG, while the meta-analysis of observational studies results indicated that 'dieters' have a higher BW than 'non-dieters'. However, considering the high methodological heterogeneity and the publication bias of the studies, this result should be taken with caution. Moreover, the term 'diet' was poorly described, and we observed a large heterogeneity of the methods used to assess dieting status. Present results suggest that dieting could be a major risk factor for WG in the long term in NW individuals. There is, however, a real need for prospective randomised controlled studies, specifically assessing the relationship between WL induced by diet and subsequent weight in this population.

Modeling BMI z score lability during childhood as a function of child temperament and genetic risk for obesity

OBJECTIVE

This study aimed to examine whether child genetic risk for obesity and temperament (i.e., negative affectivity, effortful control) accounted for stability versus lability in children's weight status (BMI z score) over time.

METHODS

A total of 561 adopted children (42% female; 56% Caucasian, 13% African American, 11% Latino, and 20% other) and their birth and adoptive parents were followed from birth to age 9 years. The multilevel location-scale model was used to examine whether child genetic risk for obesity and temperament were related to differences in level and lability in child BMI z scores over time.

RESULTS

For the full sample, higher levels of child negative affectivity were associated with greater BMI z score lability, whereas higher levels of effortful control and children's mean-level BMI z scores were related to less lability across childhood. Additional analyses examined associations within groups of children with healthy versus overweight/obesity weight statuses. Within the healthy weight status group only, better effortful control was associated with more stable BMI z scores, whereas genetic risk for higher BMI was associated with more labile BMI z scores.

CONCLUSIONS

These findings provide insights into factors that can be harnessed to redirect unhealthy trajectories as well as factors that may challenge redirection or maintain a healthy trajectory.

Identifying Ferroptosis-Related Genes Associated with Weight Loss Outcomes and Regulation of Adipocyte Microenvironment

SCOPE

The study is about the influence of ferroptosis-related genes combined with the immune microenvironment exerted on weight control outcomes and systematic analysis.

METHODS AND RESULTS

Subcutaneous adipose tissue (sWAT) samples from 11 subjects with good outcome and 10 subjects with poor outcome in weight management are obtained from the Gene Expression Omnibus database. The results are validated in vivo in animal models with different weight loss outcomes. The CIBERSORT algorithm is used to evaluate the differences in immune cell infiltration in each sample. Patients with poor outcome have higher levels of ferroptosis in the adipose tissue. Remarkable differences in cytokine production, nuclear factor kappa-B(NF-κB) transcription factor activity, leukocyte migration involved in the inflammatory response, and other biological processes are also observed compared to that in the well-controlled group. Aldo-keto reductase family 1-member C1(AKR1C1), nuclear receptor coactivator 4(NCOA4), and glutamate-cysteine ligase catalytic subunit(GCLC) are identified as core predictive markers and their expression patterns are confirmed in animal models.

CONCLUSIONS

Ferroptosis and its mediated inflammation play an important role in long-term weight control, and analyses of the role of ferroptosis-related genes(FRGs) in weight control may provide new potential therapeutic targets for long-term weight control. Anti-inflammatory diets that mitigate inflammatory responses and affect ferroptosis may be considered in the future to improve weight control.

Intuitive and mindful eating to improve physiological health parameters: a short narrative review of intervention studies

OBJECTIVES

This brief narrative review aims to give an up-to-date overview of intuitive and mindful eating (I/ME) interventions with specific focus on cardiometabolic risk factors, including glucose, lipid profile, blood pressure and inflammatory markers.

CONTENT

I/ME intervention studies in adults which measured at least one physiological parameter other than weight were identified from PubMed. The clinical trial/randomized controlled trial filters and publication dates 2001 through April 2021 with variations of the following keywords were applied: intuitive eating, mindful eating, weight neutral. Ten articles were identified.

SUMMARY AND OUTLOOK

Of the 10 studies, seven showed I/ME interventions were more effective than control in at least one cardiometabolic outcome, two showed significant I/ME within-group improvements but no between-group differences, and one showed neither within-group nor between-group differences. Specifically, I/ME improved glucose levels among pregnant women with or without gestational diabetes, lipid profile among adults with overweight or obesity, blood pressure among participants with overweight and inflammatory markers among post-menopausal women with obesity. However, the positive impact of I/ME on each of these cardiometabolic parameters was not consistent across studies: of the six studies that examined glucose regulation, two demonstrated positive outcomes for I/ME group, whereas four found no effect compared to control. Three out of five studies had positive lipid effects, one out of five demonstrated systolic blood pressure (SBP) improvements and one of two showed improvements in inflammatory markers. Given these mixed results, more research is needed to understand the possible effectiveness of I/ME to improve cardiometabolic health.

Weekly, Seasonal, and Festive Period Weight Gain Among Australian Adults

Importance

Obesity is a major global health concern. A better understanding of temporal patterns of weight gain will enable the design and implementation of interventions with potential to alter obesity trajectories.

Objective

To describe changes in daily weight across 12 months among Australian adults.

Design, Setting, and Participants

This cohort study conducted between December 1, 2019, and December 31, 2021 in Adelaide, South Australia, involved 375 community-dwelling adults aged 18 to 65 years. Participants wore a fitness tracker and were encouraged to weigh themselves, preferably daily but at least weekly, using a body weight scale. Data were remotely gathered using custom-developed software.

Exposure

Time assessed weekly, seasonally, and at Christmas/New Year and Easter.

Main Outcomes and Measures

Data were visually inspected to assess the overall yearly pattern in weight change. Data were detrended (to remove systematic bias from intraindividual gradual increases or decreases in weight) by calculating a line of best fit for each individual's annual weight change relative to baseline and subtracting this from each participant's weight data. Multilevel mixed-effects linear regression analysis was used to compare weight across days of the week and seasons and at Christmas/New Year and Easter.

Results

Of 375 participants recruited, 368 (mean [SD] age, 40.2 [5.9] years; 209 [56.8%] female; mean [SD] baseline weight, 84.0 [20.5] kg) provided at least 7 days of weight data for inclusion in analyses. Across the 12-month period, participants gained a median of 0.26% body weight (218 g) (range, -29.4% to 24.0%). Weight fluctuated by approximately 0.3% (252 g) each week, with Mondays and Tuesdays being the heaviest days of the week. Relative to Monday, participants' weight gradually decreased from Tuesday, although not significantly so (mean [SE] weight change, 0.01% [0.03%]; P = .83), to Friday (mean [SE] weight change, -0.18% [0.03%]; P < .001) and increased across the weekend to Monday (mean [SE] weight change for Saturday, -0.16% [0.03%]; P < .001; mean [SE] weight change for Sunday, -0.10% [0.03%]; P < .001). Participants' weight increased sharply at Christmas/New Year (mean [SE] increase, 0.65% [0.03%]; z score, 25.30; P < .001) and Easter (mean [SE] weight change, 0.29% [0.02%], z score, 11.51; P < .001). Overall, participants were heaviest in summer (significantly heavier than in all other seasons), were lightest in autumn (mean [SE] weight change relative to summer, -0.47% [0.07%]; P < .001), regained some weight in winter (mean [SE] weight change relative to summer, -0.23% [0.07%]; P = .001), and became lighter in spring (mean [SE] weight change relative to summer, -0.27% [0.07%]; P < .001).

Conclusions and Relevance

In this cohort study of Australian adults with weekly and yearly patterns in weight gain observed across 12 months, high-risk times for weight gain were Christmas/New Year, weekends, and winter, suggesting that temporally targeted weight gain prevention interventions may be warranted.

Weight cycling and risk of clinical adverse events in patients with heart failure with preserved ejection fraction: a post-hoc analysis of TOPCAT

Background

Previous studies hardly evaluated the association of variability of body mass index (BMI) or waist circumference with clinical adverse events and investigated whether weight cycling had an effect on the prognosis of patients with heart failure with preserved ejection fraction (HFpEF).

Methods

This study was a post-hoc analysis of TOPCAT. Three outcomes were evaluated: the primary endpoint, cardiovascular disease (CVD) death, and heart failure hospitalization. Among them, CVD death and hospitalization were outcomes of heart failure. Kaplan-Meier curves were used to describe the cumulative risk of outcome and were tested using the log-rank test. Cox proportional hazards regression models were used to calculate hazard ratios (HRs) and 95%CIs for outcomes. We also performed a subgroup analysis, and several subgroups were compared.

Results

A total of 3,146 patients were included. In the Kaplan-Meier curves, the coefficients of variation of both BMI and waist circumference were grouped according to quartiles, with the Q4 group having the highest cumulative risk (log-rank P < 0.001). In the coefficient of BMI variation and the outcomes, the HRs for group Q4 of coefficient of variation of BMI were 2.35 (95%CI: 1.82, 3.03) for the primary endpoint, 2.40 (95%CI: 1.69, 3.40) for death, and 2.33 (95%CI: 1.68, 3.22) for HF hospitalization in model 3 (fully adjusted model) compared with group Q1. In the coefficient of waist circumference variation and the outcomes, group Q4 had increased hazard of the primary endpoint [HR: 2.39 (95%CI: 1.84, 3.12)], CVD death [HR: 3.29 (95%CI: 2.28, 4.77)], and HF hospitalization [HR: 1.98 (95%CI 1.43, 2.75)] in model 3 (fully adjusted model) compared with group Q1. In the subgroup analysis, there was a significant interaction in the diabetes mellitus subgroup (P for interaction = 0.0234).

Conclusion

Weight cycling had a negative effect on the prognosis of patients with HFpEF. The presence of comorbid diabetes weakened the relationship between waist circumference variability and clinical adverse events.

Obesity and Cardiovascular Risk: Systematic Intervention Is the Key for Prevention

Obesity is a serious public health issue and associated with an increased risk of cardiovascular disease events and mortality. The risk of cardiovascular complications is directly related to excess body fat mass and ectopic fat deposition, but also other obesity-related complications such as pre-type 2 diabetes, obstructive sleep apnoea, and non-alcoholic fatty liver diseases. Body mass index and waist circumference are used to classify a patient as overweight or obese and to stratify cardiovascular risk. Physical activity and diet, despite being key points in preventing adverse events and reducing cardiovascular risk, are not always successful strategies. Pharmacological treatments for weight reduction are promising strategies, but are restricted by possible safety issues and cost. Nonetheless, these treatments are associated with improvements in cardiovascular risk factors, and studies are ongoing to better evaluate cardiovascular outcomes. Bariatric surgery is effective in reducing the incidence of death and cardiovascular events such as myocardial infarction and stroke. Cardiac rehabilitation programs in obese patients improve cardiovascular disease risk factors, quality of life, and exercise capacity. The aim of this review was to critically analyze the current role and future aspects of lifestyle changes, medical and surgical treatments, and cardiac rehabilitation in obese patients, to reduce cardiovascular disease risk and mortality, and to highlight the need for a multidisciplinary approach to improving cardiovascular outcomes.

Weight cycling based on altered immune microenvironment as a result of metaflammation

As a result of the obesity epidemic, more people are concerned about losing weight; however, weight regain is common, leading to repeated weight loss and weight cycling. The health benefits of early weight loss are nullified by weight regain after weight cycling, which has much more severe metabolic consequences. Weight cycling alters body composition, resulting in faster fat recovery and slower muscle reconstruction. This evident fat accumulation, muscle loss, and ectopic fat deposition destroy the intestinal barrier, increase the permeability of the small intestinal epithelium, and cause the lipotoxicity of lipid metabolites and toxins to leak into extraintestinal tissues and circulation. It causes oxidative stress and hypoxia in local tissues and immune cell infiltration in various tissues, all contributing to the adaptation to this metabolic change. Immune cells transmit inflammatory responses in adipose and skeletal muscle tissue by secreting cytokines and adipokines, which mediate immune cell pathways and cause metaflammation and inefficient metabolic degradation. In this review, we focus on the regulatory function of the immunological microenvironment in the final metabolic outcome, with a particular emphasis on the cellular and molecular processes of local and systemic metaflammation induced by weight cycling-induced changes in body composition. Metaflammation in adipose and muscle tissues that is difficult to relieve may cause weight cycling. As this chronic low-grade inflammation spreads throughout the body, metabolic complications associated with weight cycling are triggered. Inhibiting the onset and progression of metabolic inflammation and enhancing the immune microenvironment of adipose and muscle tissues may be the first step in addressing weight cycling.

Are Current Guidelines Perpetuating Weight Stigma? A Weight-Skeptical Approach to the Care of Patients with Obesity

Significant controversy exists regarding the evidence to support the clinical benefits and risks of weight loss interventions for individuals with obesity. United States Preventative Task Force (USPSTF) guidelines recommend weight loss for all individuals with obesity while weight-neutral models such as Health at Every Size promote weight inclusivity, focusing on body acceptance rather than weight loss. We discuss how lifestyle-based weight-centric paradigms, such as the USPSTF Guidelines, may increase weight stigma and weight cycling, and many of their purported clinical benefits are not supported by existing evidence. However, we also acknowledge the clear benefits of metabolic surgery in high-risk individuals, and the potential benefits for pharmacotherapy for obesity in selected patients. Herein we describe a weight-skeptical approach to the care of patients with obesity that aims to use available evidence to support patient-centered care.

Effect of intensive lifestyle intervention on the association between weight variability and major adverse cardiovascular events in overweight or obese adults with type 2 diabetes mellitus

AIMS/INTRODUCTION

Weight variability is associated with cardiovascular outcomes in diabetic patients. However, whether the guideline-recommended intensive lifestyle intervention (ILI) will affect this association in overweight or obese adults with diabetes is not well established.

MATERIALS AND METHODS

In 3,859 participants from the Action for Health in Diabetes (Look AHEAD) trial, the associations of 4 year weight variability measured by variability independent of the mean (VIM) with major adverse cardiovascular event (MACE) and secondary outcomes in ILI and diabetes support & education (DSE) arm were evaluated.

RESULTS

During a median follow-up of 9.6 years, 255 (12.9%) participants in the ILI arm and 247 (13.2%) participants in the DSE arm developed MACE. Participants with the highest quartile of weight variability (VIM Q4) experienced a 2.23-fold higher risk of MACE compared with the lowest quartile (VIM Q1) in the DSE arm (hazard ratio [HR] 2.23; 95% CI 1.51-3.30). Compared with the lowest weight variability (VIM Q1), participants with the highest weight variability (VIM Q4) were associated with higher risks of secondary cardiovascular composite outcome (HR 1.88; 95% CI 1.20-2.95), all-cause mortality (HR 3.19; 95% CI 1.75-5.82), and myocardial infarction (HR 1.95; 95% CI 1.12-3.37) in the DSE arm.

CONCLUSIONS

Among the overweight or obese individuals with type 2 diabetes mellitus, rising weight variability was independently associated with increased MACE risks in the DSE arm. Therefore, a guideline-recommended ILI strategy for weight loss should be adopted to improve cardiovascular outcomes without worrying about the effect of weight fluctuations.

Motives and Barriers Affecting the Participation of Polish People in the Physical Activity of Nordic Walking

The aim of the study was to identify motives and barriers which have the greatest influence on participation in Nordic Walking (NW) of people with normal body weight and persons who are either overweight or obese (according to their BMI). In the study, the modified Physical Activity and Leisure Motivation Scale (PALMS) was used, which was designed to measure adult physical activity (PA) motivation. PALMS measures eight motives for participation in PA, on a 5-point Likert scale. The study was conducted during a NW competition and during training sessions of its participants. Two groups of respondents were taken into account: the first group with those with normal body weight and the second group with those who were overweight or obese. Respondents with normal body weight were more frequent participants of NW sessions. Enhanced body capacity, concern for one's health, improved body shape and lifespan extension were major motives of practicing NW. Polish people perceive PA as a means of improving the quality of life due to enhanced health and wellbeing. Subjects with normal body weight tended to mention lack of areas suitable for NW and lack of time due to professional work. Overweight or obese persons pointed to other types of PA, shyness and lack of time.

"Bulking and cutting" among a national sample of Canadian adolescents and young adults

PURPOSE

First, to characterize the prevalence and incidence of "bulk" and "cut" cycles among Canadian adolescents and young adults. Second, to determine the associations between bulk and cut cycle engagement and drive for muscularity and eating disorder and muscle dysmorphia psychopathology.

METHODS

Data were from the Canadian Study of Adolescent Health Behaviors (2021; N = 2762), a national study of Canadian adolescents and young adults aged 16-30 years (M = 22.9, SD = 3.9). Prevalence and mean incidence of bulk and cut cycles in both the past 12 months and 30 days were estimated. Modified Poisson regressions were estimated to determine the associations between bulk and cut cycle engagement and levels of drive for muscularity and eating disorder and muscle dysmorphia psychopathology.

RESULTS

The sample comprised of 53.5% women, 38.4% men, and 8.1% transgender/gender non-conforming (TGNC) individuals. Nearly half (48.9%) of men and one in five women (21.2%) and TGNC (21.9%) participants reported bulk and cut cycles in the past 12 months. TGNC participants and women reported a greater mean number of bulk and cut cycles completed compared to men. Engagement in bulk and cut cycles was associated with stronger drive for muscularity across the sample, and more severe eating disorder and muscle dysmorphia psychopathology among men and women.

CONCLUSION

Findings underscore the common incidence and accompanying psychopathology of bulk and cut cycles among a community sample of adolescents and young adults in Canada, indicating the need for future research, as well as clinical and public health efforts.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

High-protein diet prevents fat mass increase after dieting by counteracting Lactobacillus-enhanced lipid absorption

Dietary restriction is widely used to reduce fat mass and lose weight in individuals with or without obesity; however, weight regain after dieting is still a big challenge, and the underlying mechanisms remain largely elusive. Here we show that refeeding after various types of dieting induces quick fat accumulation in mice and enhanced intestinal lipid absorption contributes to post-dieting fat mass increase. Moreover, refeeding after short-term dietary restriction is accompanied by an increase in intestinal Lactobacillus and its metabolites, which contributes to enhanced intestinal lipid absorption and post-dieting fat mass increase; however, refeeding a high-protein diet after short-term dietary restriction attenuates intestinal lipid absorption and represses fat accumulation by preventing Lactobacillus growth. Our results provide insight into the mechanisms underlying fat mass increase after dieting. We also propose that targeting intestinal Lactobacillus to inhibit intestinal lipid absorption via high-protein diet or antibiotics is likely an effective strategy to prevent obesity after dieting.

Weight Cycling in Women: Adaptation or Risk?

Obesity, dieting, and weight cycling are common among reproductive-age women. Weight cycling refers to intentional weight loss followed by unintentional weight regain. Weight loss is accompanied by changes in gut peptides, adipose hormones, and energy expenditure that promote weight regain to a tightly regulated set point. While weight loss can improve body composition and surrogate markers of cardiometabolic health, it is hypothesized that the weight regain can result in an overshoot effect, resulting in excess weight gain, altered body composition, and negative effects on surrogate markers of cardiometabolic health. Numerous observational studies have examined the association of weight cycling and health outcomes. There appears to be modest association between weight cycling with type 2 diabetes mellitus and dyslipidemia in women, but no association with hypertension, cardiovascular events, and overall cancer risk. Interestingly, mild weight cycling may be associated with a decreased risk of overall and cardiovascular mortality. Little is known about the effects of weight cycling in the preconception period. Although obesity and weight gain are associated with pregnancy complications, preconception weight loss does not appear to mitigate the risk of most pregnancy complications related to obesity. Research on preconception weight cycling may provide insight into this paradox.

The perceived role of food and eating among turkish women with obesity: A qualitative analysis

The studies show the link between Body Mass Index (BMI) and higher food responsiveness despite negative physical, social, and psychological outcomes. The descriptive studies examining what makes individuals with higher BMI values more likely to respond to food are limited, while there is none in the Turkish sample. This study aims to understand the subjective relationship of women with obesity/overweight related to food in Turkish culture. Turkish adult women (aged 22-54) who have BMI higher than 25 (overweight/obesity) participated in semi-structured interviews focusing on how they relate to food and obesity. Participants were reached through Ankara Etlik Zübeyde Hanım Obstetrics and Gynecology Hospital Obesity outpatient service. Audio-recorded interviews were analyzed predominantly inductively by thematic analysis principles. Analysis of these interviews reflected three main themes: (1) the act of eating: "I don't know why I eat when I'm full", (2) being overweight: "I am the kind of person who constantly tries to lose weight", and (3) sources of distress. The results indicated the dynamic relationship between the desire to eat, chronic stress, perceived unavailability of close ones, and low sense of self-worth among adult women with obesity/overweight. The other indication is the effect of culture in shaping the relationship dynamics, the sources of distress, and the eating patterns in developing and maintaining obesity.

Effective strategies in ending weight stigma in healthcare

Weight stigma impacts negatively healthcare quality and hinders public health goals. The aim of this review was to identify strategies for minimizing weight bias among healthcare professionals and explore future research directions. An electronic search was performed in PubMed, PsycINFO and Scopus (until June 2020). Studies on weight stigma reduction in healthcare students, trainees and professionals were assessed based on specific inclusion and exclusion criteria. A narrative synthesis was undertaken to analyze emerging themes. We identified five stigma reduction strategies in healthcare: (i) increased education, (ii) causal information and controllability, (iii) empathy evoking, (iv) weight-inclusive approach, and (v) mixed methodology. Weight stigma needs to be addressed early on and continuously throughout healthcare education and practice, by teaching the genetic and socioenvironmental determinants of weight, and explicitly discussing the sources, impact and implications of stigma. There is a need to move away from a solely weight-centric approach to healthcare to a health-focused weight-inclusive one. Assessing the effects of weight stigma in epidemiological research is equally important. The ethical argument and evidence base for the need to reduce weight stigma in healthcare and beyond is strong. Although evidence on long-term stigma reduction is emerging, precautionary action is needed.

Accept Yourself! A Pilot Randomized Controlled Trial of a Self-Acceptance-Based Treatment for Large-Bodied Women With Depression

A pilot parallel randomized controlled trial compared a self-acceptance, non-weight-loss intervention, Accept Yourself! (AY), to a weight loss program, Weight Watchers (WW), in order to provide preliminary safety, feasibility, and efficacy data in preparation for a definitive RCT of AY as an intervention to enhance the mental and physical health of larger-bodied women with Major Depressive Disorder (MDD). Adult women with MDD and a Body Mass Index ≥30 were eligible. Nineteen women were randomized by random number table into AY (n = 9) or WW (n = 10). Intake, pretreatment, posttreatment, 3-, 6-, 9-, and 12-month follow-up assessments occurred at a rural academic medical center. Primary outcomes included depression severity and cardiovascular fitness. Chi-square and t-tests assessed attrition and participant preferences for treatment; other analyses used intention-to-treat, linear mixed-effects models for repeated measures, including all participants' available data. Both groups improved in self-reported, F(5, 43.81) = 7.45, p < .001, partial η² = .38, and blinded-clinician-rated depression, F(6, 62.03) = 10.41, p < .001, partial η² = .5. AY was superior to WW in self-reported depression, F(5, 43.81) = 2.72, p = .03, partial η² = .11. Neither group improved in fitness. Eating disorder symptoms and weight gain worsened in WW. AY appeared safe, feasible, and offered initial evidence of efficacy for depression; it should be investigated in a definitive RCT, with modifications to increase potency. WW may not be suitable as a comparator intervention for AY because of risk to participants.

Weight management behaviours mediate the relationship between weight cycling, BMI and diet quality among US Army Soldiers

Weight cycling is prevalent in sports/professions with body composition standards, and has been associated with weight management behaviours that may contribute to suboptimal diet quality and weight gain. US Army Soldiers may be at increased risk of weight cycling relative to civilians due to mandated body composition standards. However, the relationship between weight cycling, weight management behaviours, BMI and diet quality among Soldiers is unknown. In this cross-sectional study, 575 Soldiers (89 % enlisted, 90 % male, 23 ± 4 years) at Army installations at Joint Base Elmendorf-Richardson, AK, Joint-Base Lewis McChord, WA, and Fort Campbell, KY completed questionnaires on food frequency, health-related behaviours and history of weight cycling (≥ 3 weight fluctuations ≥ 5 % body weight). Weight cycling was reported by 33 % of Soldiers. Those who reported weight cycling reported higher BMI (27 ± 4 v. 25 ± 3 kg/m², P < 0·001) and higher prevalence of engaging in weight management behaviours prior to body weight screening but did not report lower dietary quality (Healthy Eating Index-2015 (HEI) scores 59 ± 10 v 59 ± 11, P = 0·46) relative to those who did not report weight cycling. Results of mediation analyses suggested that weight cycling may affect BMI both directly (c' = 1·19, 95 % CI: 0·62, 1·75) and indirectly (ab = 0·45, 95 % CI: 0·19, 0·75), and HEI scores indirectly (ab = 0·69, 95 % CI: 0·20, 1·35) through the adoption of weight management behaviours. Weight cycling is common in Soldiers and is associated with higher BMI and higher prevalence of engaging in weight management behaviours that mediate associations between weight cycling, BMI and diet quality.

Body mass index trajectories and their predictors in undergraduate students from Canada: Results from the GENEiUS study

Objective: To explore the patterns and predictors of body mass index (BMI) change among undergraduate students from Ontario (Canada). Participants: 68 undergraduate students were followed longitudinally for 3 years with anthropometric data collected bi-annually. Methods: BMI measurements were plotted to generate individual BMI trajectory curves, which were categorized, based on the observed trajectory pattern. Within and between group comparisons of BMI were conducted via nonparametric paired tests. The association of baseline BMI, sex, and ethnicity with BMI trajectory type was assessed using multinomial logistic regression. Results: Four BMI trajectory types were observed: "stable weight" (n = 15, 22.1%), "weight gain" (n = 30, 44.1%), "weight loss" (n = 12, 17.6%), and "weight cycling" (n = 11, 16.2%) trajectories. Higher baseline BMI was significantly associated with the "weight gain," "weight loss," and the "weight cycling" trajectories as compared to the "stable weight" trajectory type. Conclusions: Our findings demonstrate an association between high baseline BMI and "nonstable" subsequent BMI change patterns among Canadian students.

The consequences of a weight-centric approach to healthcare: A case for a paradigm shift in how clinicians address body weight

Current healthcare is weight-centric, equating weight and health. This approach to healthcare has negative consequences on patient well-being. The aim of this article is to make a case for a paradigm shift in how clinicians view and address body weight. In this review, we (1) address common flawed assumptions in the weight-centric approach to healthcare, (2) review the weight science literature and provide evidence for the negative consequences of promoting dieting and weight loss, and (3) provide practice recommendations for weight-inclusive care.

Lifestyle behaviors, metabolic disturbances, and weight gain in psychiatric inpatients treated with weight gain-associated medication

Many psychiatric patients suffer from overweight/obesity and subsequent metabolic disturbances, where psychotropic medication is one of the main contributors. However, the magnitude of weight gain ranges individually, which leads to questioning the role of other contributors like lifestyle factors. The present study investigated several lifestyle factors among psychiatric inpatients, their relation to biological factors, and their predictive capability for weight gain during treatment. Using a naturalistic observational study design, psychiatric inpatients of all diagnoses were followed for 4 weeks from the start of treatment with weight gain-associated medication. N = 163 participants entered the study. Lifestyle factors were assessed by patient self-report questionnaires. Body weight change over time was calculated relative to baseline body weight. Our study provides three main findings: (1) Obesity and/or metabolic syndrome (metSy) were associated with emotional eating (disinhibition), craving for fast food and sweets, and weight cycling. (2) Patients without metSy and normal BMI experienced increased sweets craving (also for women), a more positive attitude towards drugs, and an improvement of affect (also for men). (3) Sex, presence of metSy and/or drug dosage interacted with disinhibition change, sweets craving change (trend), and fast food craving change to predict weight change over time. Furthermore, drug attitude change interacted with BMI, drug dosage, and presence of metSy to predict weight change. Lifestyle factors, especially eating behaviors, are related to metabolic disturbances and predict weight gain in interaction with clinical parameters.

The impact of weight cycling on health outcomes in animal models: A systematic review and meta-analysis

The pattern of weight loss and regain, termed "weight cycling," is common in overweight individuals. It is unclear whether the well-established benefits of weight loss persist following weight regain or whether weight cycling is harmful. Human studies of weight cycling have conflicting results reflecting limitations of the observational designs of these studies. By controlling the macronutrient content of diets in animal studies, weight cycling can be studied in a highly controlled manner, thereby overcoming the limitations of human studies. We conducted a systematic review and meta-analysis of animal studies which assessed the health consequences of weight cycling. Studies were classified into those which compared weight cycling to lifelong obesity and those which compared weight cycling to later onset obesity. There were no differences in health outcomes between weight cycled animals and those with lifelong obesity, highlighting that weight regain reverses health benefits achieved by weight loss. In comparison with animals with later onset obesity, weight cycled animals had higher fasting glucose levels and more impaired glucose tolerance following weight regain. Our review of animal studies suggests that health benefits of diet-induced weight loss do not persist after weight regain and weight cycling results in adverse metabolic outcomes.

Decreased excitability of leptin-sensitive anterior insula pyramidal neurons in a rat model of compulsive food demand

Compulsive eating is an overlapping construct with binge eating that shares many characteristics with substance use disorders. Compulsive eating may impact millions of Americans; presenting in some cases of binge eating disorders, overweight/obesity, and among individuals who have not yet been diagnosed with a recognized eating disorder. To study the behavioral and neurobiological underpinnings of compulsive eating, we employ a published rodent model using cyclic intermittent access to a palatable diet to develop a self-imposed binge-withdrawal cycle. Here, we further validated this model of compulsive eating in female Wistar rats, through the lens of behavioral economic analyses and observed heightened demand intensity, inelasticity and essential value as well as increased food-seeking during extinction. Using electrophysiological recordings in the anterior insular cortex, a region previously implicated in modulating compulsive-like eating in intermittent access models, we observed functional adaptations of pyramidal neurons. Within the same neurons, application of leptin led to further functional adaptations, suggesting a previously understudied, extrahypothalamic role of leptin in modulating feeding-related cortical circuits. Collectively, the findings suggest that leptin may modulate food-related motivation or decision-making via a plastic cortical circuit that is influenced by intermittent access to a preferred diet. These findings warrant further study of whether behavioral economics analysis of compulsive eating can impact disordered eating outcomes in humans and of the translational relevance of a leptin-sensitive anterior insular circuit implicated in these behaviors.

The association between recommended and non-recommended food scores on cardiovascular risk factors in obese and overweight adult women: a cross-sectional study

Objective

Obesity is a highly prevalent, non-communicable, disease associated with numerous comorbid complications, such as cardiovascular disease. Following a healthy diet is known to help reduce the risk of both obesity and cardiovascular disease. This study was conducted to evaluate the association of recommended food score (RFS) and none recommended food score (NRFS) with cardiovascular risk factors in overweight and obese women.

Methods

This cross-sectional study was performed on 379 overweight and obese (BMI ≥25 kg/m²) women aged 18-48 years. Anthropometric measurements and body composition analysis were assessed in all participants. Dietary intake was assessed by a valid and reliable food frequency questionnaire (FFQ) containing 147 items, and RFS and NRFS was calculated. Biochemical assessments including TC, HDL, LDL, TG, FBS, insulin, HOMA-IR, and hs-CRP were quantified by ELISA.

Results

The mean age and BMI of participants were 36.73 ± 9.21 (y) and 31.17 ± 4.22 (kg/m²), respectively. Binary logistic regression showed that participants in the highest tertile of the RFS compared to the lowest tertile had 57% lower odds for hypertriglyceridemia [OR = 0.43, 95%CI = 0.20-0.92, P = 0.03]. Subjects with high adherence to the NRFS had lower HDL [OR = 2.11, 95%CI = 1.08-4.12, P = 0.02] and higher odds for hypertriglyceridemia [OR = 2.95, 95%CI = 1.47-5.94, P = 0.002] compared to low adherence.

Conclusions

There was an inverse significant association between adherence to RFS and odds of hypertriglyceridemia. There was a significant association between NRFS and hypertriglyceridemia, in addition to an inverse association between NRFS and HDL. We recommend that people increase their consumption of fruits, vegetables, whole grains, lean meats or meat alternates, and low-fat dairy and avoid red meat, processed meat, chips, high-fat dairy, solid oil, refined grains, and variety of sweetened foods to prevent cardiovascular disease.

The Benefits of Physical Activity for People with Obesity, Independent of Weight Loss: A Systematic Review

Purposeful weight loss continues to be the primary focus for treating obesity. However, this strategy appears to be inadequate as obesity rates continue to rise and a myriad of benefits of physical activity that affect multiple health outcomes related to obesity and associated comorbidities are not integrated into treatment strategies. There are emerging correlational data in individuals with obesity that demonstrate physical activity can be beneficial to many critical health markers, independent of weight loss or changes in BMI. This systematic review investigates interventional studies that examine health markers, independent of weight loss, in individuals with obesity. Fourteen studies were identified that utilized a variety of physical activity interventions with primary endpoints that included cellular, metabolic, systemic and brain health outcomes. The review of the literature demonstrates that for individuals with obesity, there are both small-scale and large-scale physiologic benefits that occur with increased physical activity of various modalities. Focusing on these benefits, rather than a narrow focus of weight loss alone, may increase physical activity behavior and health for individuals with obesity.

The association between diabetes and hypertension with the number and extent of weight cycles determined from 6 million participants

The purpose of this study was to elucidate the association between weight cycling and clinical outcomes such as type 2 diabetes and hypertension with differential effects of baseline age and obesity. Nationwide data from 6,132,569 healthy adults who underwent five or more health screenings between 2002 and 2011 were analyzed and followed until December 2019 for type 2 diabetes and hypertension. Weight cycling was defined as a change in body weight followed by another change in the opposite direction. Through the Cox proportional hazards model, the number and degree of weight cycles were positively associated with increased risk of type 2 diabetes and hypertension. The hazard ratios (HRs) of weight cycling for type 2 diabetes and hypertension were as high as 1.263 (1.213-1.315) and 1.175 (1.144-1.207) at two or more weight cycles of 10% of body weight (BW), respectively. The association was stronger for females, individuals with normal body weight/BMI, and older individuals. Weight cycling was significantly associated with an increased risk of adverse health outcomes and was stronger in individuals with normal BMI and females, indicating that these people should be informed about the potential risk of weight cycling.

Working with clients of higher weight in Australia: Findings from a national survey exploring occupational therapy practice

INTRODUCTION

Occupational therapists are key members of the multidisciplinary team and regularly work with people of higher weight across age groups and practice settings. There is limited existing research regarding the occupational therapy role with this client group. The aim of this study was to explore occupational therapy practice and barriers to service provision for Australian occupational therapists working with clients of higher weight.

METHODS

A cross-sectional study design using a self-administered online survey was distributed to members of the national occupational therapy professional association. The survey was designed to identify common assessments and interventions used with clients of higher weight and explore occupational therapists' perspectives on their knowledge and confidence and the barriers to service delivery. Descriptive statistics were used to summarise rating scales, and open-ended responses were analysed using thematic analysis.

RESULTS

Eighty Australian occupational therapists working in a range of settings and with varied experience levels participated in the study. Participants described the most common areas of occupational therapy assessment and intervention when working with clients of higher weight to be self-care, equipment prescription, home modifications and pressure care. Respondents were least confident in interventions related to psychosocial, leisure and employment interventions. Barriers to service delivery included accessibility and cost of equipment, lack of training and weight stigma.

CONCLUSION

Occupational therapy practice promotes and enables participation in everyday occupations with people of higher weight. This study highlights not only the occupational therapy skills and unique approach to the person, their environment and occupations but also the challenges faced by occupational therapists when working with people of higher weight. Occupational therapists could consider utilising the weight-inclusive paradigm to broaden their contribution from self-care to other important aspects of participation and well-being.

Rapid Weight Loss Practices in Grapplers Competing in Combat Sports

Background

Grappling is a wrestling style that combines different techniques such as freestyle wrestling, jiu-jitsu, judo, sambo, and others. As with other combat sports, it requires categorizing the athletes in weight classes, which leads to the use of certain methods to lose body weight in a short amount of time which poses a serious threat to athletes’ health and wellbeing. Therefore, the objective of this study was to investigate the most widespread rapid weight loss (RWL) methods and sources of influence used by grappling athletes.

Methods

A total of 145 athletes took part in the study by voluntarily filling out a questionnaire regarding their weight loss techniques and methods. They were divided into two groups, male (27.7 ± 5.2 years, 1.76 ± 0.13 m, and 82.1 ± 20 kg) and female (27.33 ± 6.3 years, 1.65 ± 0.08 m, and 64.3 ± 10.4 kg), for further statistical analysis. After calculating descriptive statistics for all the variables, a t-test was conducted for gender differences in weight loss and weight regain, and a chi-square test measured the diversity in techniques and source of influence.

Results

Out of 145 participants, 120 athletes (85.2%) reported engaging in rapid weight loss prior to weigh-in. Coaches (52.4 and 59%) and teammates (42.6 and 22.1%) seemed to be the most influential on their rapid weight-loss strategies, whereas physicians (17.1 and 17.9%) and parents (23.2 and 23.1%) were the least influential. A statistical difference between men and women (p = 0.05) was found when teammates were a source of influence (42.6 and 21.1%, respectively). Regarding the methods used, both groups practiced gradual dieting (85.4 and 79.5%) as the most prevalent, followed by increased exercise (79 and 66.6%) and sauna (78.7 and 66.6%). Moreover, men trained in plastic suits significantly more often than women (67.1 vs. 41%, p = 0.01).

Conclusion

Rapid weight loss is detrimental to athletes’ health and wellbeing. Hence, it is crucial to find and implement methods that will control and ultimately limit its use in combat sports. Physicians and nutritionists need to be closely linked with the staff, collaborate and supervise the weight cutting.

Intuitive eating buffers the link between internalized weight stigma and body mass index in stressed adults

Internalized weight stigma (IWS) is independently associated with less intuitive eating (i.e., eating based on endogenous hunger/satiety cues) and higher Body Mass Index (BMI), and intuitive eating training is commonly conceptualized as protective against the effects of IWS on poor behavioral health. The 3-way relationship between IWS, intuitive eating, and BMI has yet to be examined, and it is unclear whether the link between IWS and BMI is buffered by high intuitive eating. This secondary preliminary analysis examined baseline data of stressed adults with poor diet (N = 75, 70% female, 64.1% White, 42.7% with overweight/obesity) in a parent clinical trial that tested the effects of yoga on diet and stress. Validated self-report surveys of IWS and intuitive eating were analyzed with objectively-assessed BMI. Moderated regression analyses using the SPSS PROCESS macro tested whether intuitive eating moderated the IWS-BMI link. The analysis revealed IWS was positively associated with BMI except among people with high intuitive eating. Results extend observational findings linking intuitive eating to lower BMI, and offer preliminary support for the hypothesis that this link may hold even among those with greater IWS. It's possible that individuals with lower BMI and greater IWS may gravitate more towards intuitive eating than those with greater BMI, and/or intuitive eating may be an important target for ameliorating the adverse association of IWS with behavioral and physical health indicators linked to BMI. Continued work is warranted in larger, more generalizable samples using causal and prospective designs.

Variability of adiposity indices and incident heart failure among adults with type 2 diabetes

Background

It remains unclear how the variability of adiposity indices relates to incident HF. This study evaluated the associations of the variability in several adiposity indices with incident heart failure (HF) in individuals with type 2 diabetes (T2DM).

Methods

We included 4073 participants from the Look AHEAD (Action for Health in Diabetes) study. We assessed variability of body mass index (BMI), waist circumference (WC), and body weight across four annual visits using three variability metrics, the variability independent of the mean (VIM), coefficient of variation (CV), and intraindividual standard deviation (SD). Multivariable Cox regression models were used to generate adjusted hazard ratios (aHR) and 95% confidence intervals (CI) for incident HF.

Results

Over a median of 6.7 years, 120 participants developed incident HF. After adjusting for relevant confounders including baseline adiposity levels, the aHR for the highest (Q4) versus lowest quartile (Q1) of VIM of BMI was 3.61 (95% CI 1.91–6.80). The corresponding aHRs for CV and SD of BMI were 2.48 (95% CI 1.36–4.53) and 2.88 (1.52–5.46), respectively. Regarding WC variability, the equivalent aHRs were 1.90 (95% CI 1.11–3.26), 1.79 (95% CI 1.07–3.01), and 1.73 (1.01–2.95) for Q4 versus Q1 of VIM, CV and SD of WC, respectively.

Conclusions

In a large sample of adults with T2DM, a greater variability of adiposity indices was associated with higher risks of incident HF, independently of traditional risk factors and baseline adiposity levels.

Registration-URL:https://clinicaltrials.gov/ct2/show/NCT00000620.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01440-1.

Body Weight Variability and Risk of Cardiovascular Outcomes and Death in the Context of Weight Loss Intervention Among Patients With Type 2 Diabetes

IMPORTANCE

Body weight fluctuation is associated with greater risks of adverse health outcomes. Whether intensive weight loss interventions affect the association of variability in adiposity measures with adverse health outcomes in individuals with type 2 diabetes has not been studied previously.

OBJECTIVE

To evaluate the associations of long-term variability in adiposity indices with cardiovascular disease (CVD) outcomes and whether these associations are affected by an intensive lifestyle intervention among adults with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included participants in the Action for Health in Diabetes (Look AHEAD) trial without CVD at baseline (August 2001 to April 2004). The Look AHEAD study included 16 centers in the United States. Data analysis was performed from December 2020 to June 2021.

EXPOSURES

Variability of body mass index (BMI) and waist circumference (WC) across 4 annual visits, assessed using the coefficient of variation (CV), variability independent of the mean (VIM), and standard deviation (SD).

MAIN OUTCOMES AND MEASURES

Main outcomes were (1) all-cause mortality, (2) cardiovascular deaths (deaths from myocardial infarction [MI] or stroke), and (3) CVD events (MI, stroke, and/or death from cardiovascular causes).

RESULTS

Among 3604 study participants (mean [SD] age, 58.4 [6.6] years; 2240 [62.3%] women; 1364 [37.7%] Black participants; 2404 [66%] White participants), there were 216 CVD events, 33 CVD deaths, and 166 deaths over a median of 6.7 years. In the control group, the hazard ratios (HRs) for the highest quartile (quartile 4) compared with the lowest quartile (quartile 1) of CV of BMI were 4.06 (95% CI, 2.17-7.57), 15.28 (95% CI, 2.89-80.90), and 2.16 (95% CI, 1.21-3.87) for all-cause mortality, CVD mortality, and cardiovascular events, respectively. In the intervention group, the corresponding HRs were 0.99 (95% CI, 0.45-2.16), 1.14 (95% CI, 0.12-10.53), and 0.77 (95% CI, 0.40-1.49) for quartile 4 vs quartile 1. Regarding WC, in the control group, HRs for quartile 4 vs quartile 1 were 1.84 (95% CI, 1.01-3.35), 6.46 (95% CI, 1.16-36.01), and 1.28 (95% CI, 0.72-2.29). In the intervention group, HRs were 1.23 (95% CI, 0.61-2.46), 0.55 (95% CI, 0.15-2.11), and 0.70 (95% CI, 0.39-1.25) for quartile 4 vs quartile 1.

CONCLUSIONS AND RELEVANCE

In this cohort study of individuals with type 2 diabetes, higher variability of adiposity indices was associated with significantly increased risk of CVD outcomes and death in the control group but not in the intensive lifestyle intervention group.

Associations between weight loss history and factors related to type 2 diabetes risk in the Stop Diabetes study

Background

Frequent weight loss attempts are related to maladaptive eating behaviours and higher body mass index (BMI). We studied associations of several type 2 diabetes (T2D) risk factors with weight loss history, defined as the frequency of prior weight loss attempts, among Finnish adults at increased risk for T2D.

Methods

This study (n = 2684, 80% women) is a secondary analysis of the 1-year StopDia lifestyle intervention with digital intervention group, digital intervention + face-to-face counselling group, or control group. The frequency of prior weight loss attempts was categorized into five groups: no attempts/no attempts to lose weight, but trying to keep weight stable/1–2 attempts/3 or more attempts/ continuous attempts. Data on emotional eating and social/emotional nutrition self-efficacy were collected with a digital questionnaire. We assessed baseline differences between categories of weight loss history as well as the intervention effects.

Results

Altogether 84% of participants had attempted weight loss. Those with one or more weight loss attempts had higher BMI, larger waist circumference, and more emotional eating compared to ‘no attempts’ and ‘no attempts to lose weight, but trying to keep weight stable’ categories. The ‘no attempts’ category had the highest baseline fasting insulin, whereas it showed the largest decrease in this measure with the intervention. This change in fasting insulin in the ‘no attempts’ category was significantly different from all the other categories. Emotional nutrition self-efficacy slightly improved in the ‘no attempts’ category, which was significantly different from its concomitant decrease in the categories ‘1-2 attempts’ and ‘3 or more attempts’. The intervention group assignment did not affect the results.

Conclusions

Multiple attempts to lose weight may unfavourably affect T2D risk factors as well as lifestyle intervention outcomes. More research is needed on how weight loss frequency could affect T2D risk factors and how to design lifestyle interventions for individuals with frequent previous weight loss attempts.

Weight cycling induces innate immune memory in adipose tissue macrophages

Introduction

Weight loss improves obesity-associated diabetes risk. However, most individuals regain weight, which worsens the risk of developing diabetes and cardiovascular disease. We previously reported that male mice retain obesity-associated immunological changes even after weight loss, suggesting that immune cells may remember the state of obesity. Therefore, we hypothesized that cycles of weight gain and loss, otherwise known as weight cycling, can induce innate memory in adipose macrophages.

Methods

Bone marrow derived macrophages were primed with palmitic acid or adipose tissue conditioned media in a culture model of innate immune memory. Mice also put on low fat or high fat diets over 14-27 weeks to induce weight gain, weight loss, and weight cycling.

Results

Priming cells with palmitic acid or adipose tissue conditioned media from obese mice increased maximal glycolysis and oxidative phosphorylation and increased LPS-induced TNFα and IL-6 production. Palmitic acid effects were dependent on TLR4 and impaired by methyltransferase inhibition and AMPK activation. While weight loss improved glucose tolerance in mice, adipose macrophages were primed for greater activation to subsequent stimulation by LPS ex vivo as measured by cytokine production. In the model of weight cycling, adipose macrophages had elevated metabolism and secreted higher levels of basal TNFα, suggesting that weight loss can also prime macrophages for heighted activation to weight regain.

Discussion

Together, these data suggest that weight loss following obesity can prime adipose macrophages for enhanced inflammation upon weight regain. This innate immune memory response may contribute to worsened glucose tolerance following weight cycling.