Yo-Yo Dieting Delays Male Drosophila melanogaster Aging Through Enhanced Mitochondrial Function, Relative to Sustained High-Calorie Diet Feeding

Weight regain subsequent to weight reduction resulting from dietary interventions represents a prevalent phenomenon recognized as "Yo-yo dieting." However, the impact of prolonged Yo-yo dieting on health, especially in relation to the aging process, remains poorly understood. This study aimed to investigate the influence of Yo-yo dieting on the aging process in male Drosophila melanogaster that have been exposed to a high-calorie (HC) diet. Fruit flies were fed with either a consistent HC diet or an alternating regimen of HC and low-calorie diets every 3 days (referred to as "Yo-yo dieting") for a total of 24 days. Biochemical assays were utilized to quantify levels of oxidative stress and activities of the mitochondrial respiratory chain complexes. The frozen section staining method was employed to assess the presence of lipid droplets, reactive oxygen species, cellular viability, and mitochondrial abundance in tissues. Additionally, we examined the expression of key regulators involved in mitochondrial dynamics and biogenic signaling pathways. Yo-yo dieting resulted in an extension of the fruit flies' lifespan, concomitant with reduced body weight, decreased body protein content, and lower triglyceride levels compared to continuous a HC diet feeding. Furthermore, Yo-yo dieting ameliorated impairments in motility and intestinal barrier function. Importantly, it improved mitochondrial function and upregulated the expression of essential mitochondrial fusion proteins, namely mitofusin 1 and mitofusin 2, optic atrophy 1, and peroxisome proliferator-activated receptor-γ coactivator-1α. Therefore, the practice of Yo-yo dieting extends the lifespan of fruit flies by modulating mitochondrial dynamics and the associated biogenic signaling pathways.

Weight regain, but not weight loss exacerbates hepatic fibrosis during multiple weight cycling events in male mice

PURPOSE

Weight cycling is a phenomenon characterized by fluctuating body weight that is commonly observed in individuals employing intentional weight loss methods. Despite its prevalence, the impact of weight cycling on health remains equivocal. The current investigation aimed to examine the effects of weight cycling on liver health.

METHODS

The weight cycling model was established by switching the feeding method of mice between ad libitum (AL) and restricted intake (DR or 60% of AL) of the breeding diet to cause weight gain and weight loss, respectively. The weight cycling model comprised two and a half cycles, with one group terminating the experience during the weight-gain period (S-AL) and the other during the weight-loss period (S-DR). Liver tissue was collected to investigate morphology alterations, apoptosis, lipid metabolism, and mitochondrial homeostasis.

RESULTS

The results demonstrated that the termination point of weight cycling affected body weight and hepatic steatosis. All parameters examined in the S-DR mice exhibited a comparable trend to those observed in the DR mice. Notably, S-AL mice showed a significant increase in lipid metabolism-related proteins in the liver compared to AL-fed mice, along with reduced lipid droplets. Moreover, hepatic apoptosis and fibrosis were exacerbated in the S-AL mice compared to AL mice, whereas mitochondrial fusion, biogenesis, and mitophagy were decreased in the S-AL mice.

CONCLUSION

Weight cycling ending in weight gain exacerbated hepatic fibrosis, potentially by inducing apoptosis or disrupting mitochondrial homeostasis. Conversely, weight cycling ending in weight loss demonstrated beneficial effects on hepatic health.

The relationship between psychological distress and weight maintenance in weight cycling: mediating role of eating behavior

BACKGROUND

Obesity is a global public health concern. The goal of this study was to see if eating habits could mediate the relationship between psychological distress and weight maintenance in a population with a history of weight cycling.

METHODS

A 3-month outpatient intervention consisting of a diet and exercise program was provided to 153 participants. Psychological distress, appetite, and behavior were assessed at the beginning and end of the study. Anthropometric measurements were taken at baseline and six months.

RESULTS

After the structural equation model was developed, it was discovered that the psychological status of people with obesity and weight cycling histories correlated with the weight loss outcome effect (three and six months). This effect was mediated by factors related to eating behavior. Associative psychological factors had a direct effect on eating behavior (three months: β = 0.181, 95% CI: 0.055-0.310; six months: β = 0.182, 95% CI: 0.039-0.332) and appetite had a direct effect on eating behavior (three months: β = 0.600, 95% CI: 0.514-0.717; six months: β = 0.581, 95% CI: 0.457-0.713), both of which were significant (p < 0.01). At three months, psychological distress has a more substantial positive impact on weight change, with eating behavior acting as a partial mediator. At six months, there was no support for appetite's moderating role in eating behavior.

CONCLUSIONS

The findings suggest that psychological interventions should be strengthened to improve weight loss effectiveness, particularly in participants with a history of weight cycling, making weight loss more complicated and prone to rebound.

CLINICAL TRIAL REGISTRATION

The study has been registered in Clinical Trials (NCT05311462).

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.

Energy Balance and Bone Health: a Nutrient Availability Perspective

PURPOSE OF REVIEW

Obesity is highly prevalent and is associated with bone fragility and fracture. The changing nutrient availability to bone in obesity is an important facet of bone health. The goal of this article is to summarize current knowledge on the effects of carbohydrate and dietary fat availability on bone, particularly in the context of other tissues.

RECENT FINDINGS

The skeleton is a primary site for fatty acid and glucose uptake. The trafficking of carbohydrates and fats into tissues changes with weight loss and periods of weight gain. Exercise acutely influences nutrient uptake into bone and may affect nutrient partitioning to bone. Bone cells secrete hormones that signal to the brain and other tissues information about its energetic state, which may alter whole-body nutrient trafficking. There is a critical need for studies to address the changes that metabolic perturbations have on nutrient availability in bone.

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.

soldiers

Negative body image is more often identified in individuals with overweight or obesity. More than 65% of U.S. soldiers have a body mass index (BMI) that classifies them with overweight or obesity. Additionally, all soldiers must meet body composition and physical fitness standards which may increase the risk of negative body image. This cross-sectional study aimed to identify associations between compliance with body composition standards, body image, and weight cycling through surveying 969 active-duty soldiers (86% male, 24.0 ± 5.5 years of age, BMI 26.0 ± 3.6 kg/m²). Compliance with body composition standards was measured by whether a soldier had ever taken and failed the circumference-based body fat assessment. Weight cycling was self-reported as ≥3 weight fluctuations of ≥5% of body weight during their military career. Multivariate linear and logistic regression models were used to examine the relationship between compliance with body composition standards, body image, weight cycling, and sociodemographic characteristics while controlling for BMI. Failing the circumference-based body fat assessment was associated with increased concern with conforming to military image. Negative body image was associated with higher odds of weight cycling. Further examination is warranted to understand the effects of body composition standards on soldiers' body image and weight cycling.

Association between weight cycling and risk of kidney cancer: a prospective cohort study and meta-analysis of observational studies

PURPOSE

Weight cycling is common in populations. However, it is unclear whether frequency and magnitude of weight cycling is associated with kidney cancer risk, independent of body mass index (BMI).

METHODS

A prospective cohort study followed 85,562 participants from Health Professionals Follow-up Study and Nurses' Health Study (1992-2014). At baseline, participants reported frequency and magnitude of intentional weight loss in the past 4 years. Cox proportional hazard model was used to estimate hazard ratios (HR) and 95% confidence intervals (CI). We also conducted a meta-analysis of all available observational studies including our two cohorts.

RESULTS

During 22 years of follow-up, we identified 441 kidney cancer cases. Compared with non-weight cyclers (no attempt of intentional weight loss), severe cyclers (≥ 3 times of intentional weight loss of ≥ 4.5 kg) were at increased kidney cancer risk after adjusting for BMI before weight cycling (pooled multivariable-adjusted HR, 1.78; 95% CI, 1.19, 2.66). Additional adjustment for attained BMI after weight cycling had minimal influence. There was a positive trend between weight cycling by frequency and magnitude and kidney cancer risk (P-trend = 0.01). Moreover, the observed positive association did not differ by subtypes of cyclers (e.g., adiposity status, weight-loss methods). In the meta-analysis, we found a strong positive association between weight cycling and kidney cancer risk (summary relative risk for weight cyclers vs. non-cyclers, 1.51; 95% CI, 1.16, 1.96; I²: 52.2%; 6 studies).

CONCLUSION

Frequent substantial weight cycling was associated with increased risk of kidney cancer, independent of BMI. Our study suggests that weight cycling may be an important risk factor for kidney cancer.

The hamster wheel: a case study on embodied narrative identity and overcoming severe obesity

Based in narrative phenomenology, this article describes an example of how lived time, self and bodily engagement with the social world intertwine, and how our sense of self develops. We explore this through the life story of a woman who lost weight through surgery in the 1970 s and has fought against her own body, food and eating ever since. Our narrative analysis of interviews, reflective notes and email correspondence disentangled two storylines illuminating paradoxes within this long-term weight loss process. Thea's Medical Weight Narrative: From Severely Obese Child to Healthy Adult is her story in context of medicine and obesity treatment and expresses success and control. Thea's Story: The Narrative of Fighting Weight is the experiential story, including concrete examples and quotes, highlighting bodily struggles and the inescapable ambiguity of being and having one's body. The two storylines coexist and illuminate paradoxes within the weight loss surgery narrative, connected to meaningful life events and experiences, eating practices and relationships with important others. Surgery was experienced as lifesaving, yet the surgical transformation did not suffice, because it did not influence appetite or, desire for food in the long run. In the medical narrative of transforming the body by repair, a problematic relationship with food did not fit into the plot.

Body weight variability is not associated with changes in risk factors for cardiometabolic disease

CONTEXT

Weight loss is known to improve health, however the influence of variability in body weight around the overall trajectory on these outcomes is unknown. Few studies have measured body weight frequently enough to accurately estimate the variability component.

OBJECTIVE

To investigate the association of 12-month weight variability and concurrent weight change with changes in health markers and body composition.

METHODS

This study was a secondary analysis of the NoHoW trial, a 2 × 2 factorial randomised controlled trial promoting evidence-based behaviour change for weight loss maintenance. Outcome measurements related to cardiometabolic health and body composition were taken at 0, 6 and 12 months. Participants were provided with Wi-Fi connected smart scales (Fitbit Aria 2) and asked to self-weigh regularly over this period. Associations of weight variability and weight change with change in outcomes were investigated using multiple linear regression with multiple levels of adjustment in 955 participants.

RESULTS

Twelve models were generated for each health marker. Associations between weight variability and changes in health markers were inconsistent between models and showed no evidence of a consistent relationship, with all effects explaining <1% of the outcome, and most 0%. Weight loss was consistently associated with improvements in health and body composition, with the greatest effects seen in percent body fat (R2 = 10.4-11.1%) followed by changes in diastolic (4.2-4.7%) and systolic (3-4%) blood pressure.

CONCLUSION

Over 12-months, weight variability was not consistently associated with any measure of cardiometabolic health or body composition, however weight loss consistently improved all outcomes.

TRIAL REGISTRATION NUMBER

ISRCTN88405328.

Association between weight cycling and risk of developing diabetes in adults: A systematic review and meta-analysis

AIMS/INTRODUCTION

In this meta-analysis, we aimed to explore the association between bodyweight cycling (weight fluctuation) and the risk of developing diabetes.

MATERIALS AND METHODS

We analyzed data from eligible cohort studies that assessed the association between weight cycling in adults and the risk of developing diabetes from online databases PubMed, Cochrane Library and EMBASE databases (1966 to April 2020). We pooled data using relative risks (RRs) with a random effects model.

RESULTS

A total of 14 studies involving 253,766 participants, including 8,904 diabetes events, were included. One study included eight independent reports, resulting in 21 reports in 14 studies. Summary analysis showed that individuals who suffered weight cycling had a higher risk of diabetes (RR 1.23. 95% confidence interval 1.07-1.41; P = 0.003). However, the association between weight cycling and the risk of developing diabetes was not observed in obese participants (body mass index ≥30 kg/m² ; P = 0.08).

CONCLUSIONS

The present meta-analysis showed that weight cycling was a strong independent predictor of new-onset diabetes. Future studies are required to detect the causal links between weight cycling and the risk of developing diabetes.

Associations of weight cycling with cardiovascular health using American Heart Association's Life's Simple 7 in a diverse sample of women

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Most women reported history of weight cycling (range: 0–20 episodes).

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Any history of weight cycling was associated with poorer cardiovascular health.

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Associations were stronger in pre-menopausal and women with no pregnancy history.

Prior research shows that weight cycling is associated with poorer cardiovascular health (CVH). Women experience unique life events (e.g. pregnancy, menopause) which may make them more prone to weight cycling. Examining the influence of weight cycling history (HWC) on CVH, quantified using the American Heart Association’s Life’s Simple 7 (LS7), may provide novel targets to improve CVH. A cross-sectional sample of 485 women at Columbia University Irving Medical Center (2016–2018) were scored on each LS7 metric (BMI, blood pressure, fasting cholesterol and glucose, physical activity, diet, and smoking): 0 (low), 1 (moderate) or 2 (high). Metric points were summed into a composite LS7 score as a measure of CVH: 0–8 (low), 9–10 (moderate), 11–14 (high). Multivariable-adjusted logistic and linear regression models were used for the associations between HWC and CVH. Most women (73%) reported HWC (range: 0–20); 26% had low CVH and 74% moderate/high CVH. Logistic models showed HWC was associated with higher odds of having poor CVH [OR (95%CI): 2.39 (1.36–4.20)]. Linear models showed each additional weight cycling episode was associated with lower LS7 scores [ß(SE): −0.37 (0.07); p < 0.01]. Associations between HWC and odds of having poor CVH were stronger among pre-menopausal women and those with no pregnancy history (p-interaction = 0.009, 0.004, respectively). In conclusion, HWC was associated with higher odds of poorer CVH with stronger associations seen in pre-menopausal and women with no pregnancy history. These findings suggest that in addition to having a healthy weight, maintaining a consistent weight may be important for achieving optimal CVH, but warrant prospective confirmation.

Trajectories of body mass index among active-duty U.S. Army soldiers, 2011-2014

Establishing the shape and determinants of trajectories of body mass index (BMI) among Soldiers is critical given the importance of weight management to military service requirements. To establish the shape and determinants of BMI trajectories among Soldiers, we aimed to (1) model the overall BMI trajectory of Soldiers, (2) find the most common trajectory groups among Soldiers, (3) investigate the relationship between BMI trajectories and sociodemographic and military-specific characteristics, and (4) determine if there were Soldiers with large fluctuations in BMI. The study population included all US Army Soldiers on active-duty between 2011 and 2014 who were age 17–62 (n = 827,126). With longitudinal data from the Stanford Military Data Repository, we used group-based trajectory modeling to identify the BMI trajectories of Soldiers and multinomial logistic regression to estimate associations between Soldier characteristics and trajectory membership. Four distinct BMI trajectory groups were found: increasing, decreasing, constant, and inconstant. The constant, increasing, and decreasing trajectories were similar in shape and percentage between men and women. The constant trajectory had the fewest Soldiers who exceeded weight standards or had duty limitations. The increasing trajectory was associated with marriage and fewer service years. The decreasing trajectory was associated with more service years and higher educational attainment. The inconstant trajectory differed in shape between men and women. Over 6% of men and 12% of women had fluctuations in BMI indicative of weight cycling. Understanding the characteristics associated with BMI trends may assist the Army in targeting resources aimed to improve Soldier health and combat readiness.

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Four BMI trajectory groups were found: increasing, decreasing, constant, inconstant.

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The constant trajectory had the fewest Soldiers who exceeded weight standards.

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The increasing trajectory was associated with marriage and fewer service years.

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The decreasing trajectory was associated with more service years and education.

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6% of men and 12% of women had fluctuations in BMI indicative of weight cycling.

Comparison of low calorie high protein and low calorie standard protein diet on waist circumference of adults with visceral obesity and weight cycling

Objectives

Many individuals with visceral obesity who previously had succeeded in reducing body weight regain and this loss–gain cycle repeats several times which is called as weight cycling. We aimed to evaluate the effect of a low calorie high protein diet (HP) compared to a low calorie standard protein diet (SP) on waist circumference of visceral obese adults with history of weight cycling.

Results

In this open-randomized clinical trial, participants were asked to follow dietary plan with reduction in daily caloric intake ranging from 500 to 1000 kcal from usual daily amount with minimum daily amount of 1000 kcal for 8 weeks and were divided in two groups: HP group with protein as 22–30% total calorie intake; and SP group with protein as 12–20% total calorie intake. There was a statistically significant difference (P < 0.001) between waist circumference before and after the dietary intervention among both groups. Meanwhile, there was no statistically significant difference in the mean reduction of waist circumference between HP and SP groups (P = 0.073). Taken together, the protein proportion does not significantly affected waist circumference.

Trial registration ClinicalTrials.gov NCT03374150, 11 December 2017

Electronic supplementary material

The online version of this article (10.1186/s13104-018-3781-z) contains supplementary material, which is available to authorized users.

Increased risk of diabetes development in individuals with weight cycling over 4 years: The Kangbuk Samsung Health study

AIMS

Weight cycling is defined as cyclical loss and gain of weight and recent studies suggest deleterious effects of weight cycling on cardiometabolic health. We aimed to analyze the risk for diabetes development in association with weight cycling over 4 years of follow-up.

METHODS

A retrospective study performed in 4,818 non-diabetic participants (mean age 43 years, 78.3% men) in a health screening program in whom serial health examinations were performed in 5 consecutive years from 2010 to 2014. Average successive variability of weight (ASVW) was defined by the amount of body weight change in absolute value between the successive years over 5 years summed and divided by four. The subjects were divided into two groups according to body mass index (BMI), normal weight (<23 kg/m²) and overweight (≥23 kg/m²).

RESULTS

Over 4 years, 3.2% developed diabetes. When the subjects were divided into 3 groups according to tertile groups of ASVW, those in the highest tertile showed significantly increased risk for diabetes development compared to those with the lowest tertile {odds ratio (OR) 1.860; 95% CI 1.130-3.063}. When similar analyses were performed according to the 4 groups divided by baseline body weight and ASVW over four years, those who were more than overweight at baseline with high ASVW showed significantly increased risk of diabetes development compared to those had normal weight and low ASVW (OR 2.266; 95% 1.123-4.572). When the subjects were divided into six group according to weight change and ASVW, those with increased weight over 4 years and high ASVW showed the highest risk for diabetes development among the groups compared to those with stable weight and low ASVW over four years (OR 3.660; 95% CI 1.402-9.553).

CONCLUSIONS

Those with high ASVW showed significantly increased risk for diabetes development over four years compared with those who had low ASVW. Weight cycling was significantly associated with increased risk for diabetes.

Is weight cycling associated with adverse health outcomes? A cohort study

Evidence about the health effects of weight cycling is not consistent, with some studies suggesting it is harmful for health. Here we investigated whether weight cycling was associated with weight change and mental health outcomes in 10,428 participants in the mid-age cohort of The Australian Longitudinal Study of Women's Health (ALSWH) over 12years. In 1998 the women were asked how many times they had ever intentionally lost at least 5kg and how many times had they regained this amount. Women were categorised into four weight pattern groups: frequent weight cyclers (FWC, three or more weight cycles), low frequency weight cyclers (LFWC, one or two weight cycles), non-weight cyclers (NWC), and weight loss only (WL). We used generalised linear modelling to investigate relationships between weight pattern group, weight change and mental health outcomes. In 1998, 15% of the women were FWC, 24% LFWC, 46% NWC and 15% were WL. Weight change was similar across weight pattern groups in women with obesity, however healthy weight and overweight FWC gained more weight than women who did not weight cycle. We found no difference in overall mental health scores between groups, but both LFWC and FWC had higher odds of depressive symptoms (adjusted OR 1.5, 95%CI: 1.1 to 1.9 and 1.7, 95%CI: 1.1 to 2.4, respectively) than NWC. Our results suggest that, although weight cycling is not associated with greater weight gain in women with obesity, it may increase depressive symptoms.

Hypothalamic miR-219 regulates individual metabolic differences in response to diet-induced weight cycling

Consumption of a low calorie diet is the most common approach to lose weight. While generally effective at first, it is frequently followed by a relapse where the pre-diet weight is regained, and often exceeded. This pattern of repeated weight loss/regain is referred to as weight cycling and the resulting metabolic response varies greatly between individuals.

Objective

We attempted to address the issue of individual differences in the response to weight cycling in male mice.

Methods

We first exposed adult wild type mice to repeated cycles of high/low fat food. Next, using a lentiviral approach, we knocked-down or over-expressed miR-219 in the ventromedial hypothalamus (VMH) of an additional mouse cohort and performed a full metabolic assessment.

Results

Exposure of wild type males to weight cycling resulted in the division of the cohort into subsets of resistant versus metabolic-syndrome-prone (MS) animals, which differed in their metabolic profile and hypothalamic miR-219 levels. Lentiviral knock-down of miR-219 in the VMH led to exacerbation of metabolic syndrome. In contrast, over-expression of miR-219 resulted in moderation of the metabolic syndrome phenotype.

Conclusions

Our results suggest a role for miR-219 in the mediation of the metabolic phenotype resulting from repeated weight cycling.

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Repeated cycles of high fat diet induce different responses in adult males.

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Low miR-219 in ventromedial hypothalamus are linked to metabolic-syndrome proneness.

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Lentiviral knockdown of miR-219 induces metabolic-syndrome-prone phenotype.

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Lentiviral overexpression of miR-219 provides moderate protection from metabolic-syndrome.

Weight Cycling and Its Cardiometabolic Impact

Dieting has multiple meanings including "intentional weight loss" or "a specific eating pattern." Although obesity is considered a deleterious health problem worldwide, there are many problems caused by "too strict" weight control and the need for excessive leanness. Many people with normal weight want to lose weight, and they repeat losing and gaining weight multiple times through their lives. This is called "weight cycling." Recent studies report not just the negative impact of being obese, but also the danger of weight cycling for cardiometabolic health. Many experimental studies support that weight cycling might cause fluctuations in cardiovascular risk factors, such as blood pressure, heart rate, sympathetic activity, and circulating levels of glucose, lipids and insulin. These repeated overshoots above normal values during periods of weight regain put an additional stress on the cardiovascular system. This paper reviews current evidence for the effects of weight cycling on cardiometabolic health.

Unstable bodyweight and incident type 2 diabetes mellitus: A meta-analysis

AIMS/INTRODUCTION

The present meta-analysis aimed to clarify the association of unstable bodyweight with the risk of type 2 diabetes mellitus, an association that has been controversial among longitudinal studies.

MATERIALS AND METHODS

An electronic literature search using EMBASE and MEDLINE was followed up to 31 August 2016. The relative risks (RRs) of type 2 diabetes mellitus in individuals with unstable bodyweight were pooled using the inverse variance method.

RESULTS

Eight studies were eligible for the meta-analysis. The median duration of measurements of weight change and follow-up years for ascertaining type 2 diabetes mellitus were 13.5 and 9.4 years, respectively. The pooled RR for the least vs most stable category was 1.33 (95% confidence interval 1.12-1.57). Between-study heterogeneity was statistically significant (P = 0.048). Whether type 2 diabetes mellitus was ascertained by blood testing explained 66.0% of the variance in the logarithm of RR (P = 0.02). In three studies in which blood testing was carried out, type 2 diabetes mellitus risk was not significant (RR 1.06, 95% confidence interval 0.91-1.25). Furthermore, publication bias that inflated type 2 diabetes mellitus risk was statistically detected by Egger's test (P = 0.09).

CONCLUSIONS

Unstable bodyweight might be modestly associated with the elevated risk of type 2 diabetes mellitus; although serious biases, such as diagnostic suspicion bias and publication bias, made it difficult to assess this association.

Associations between Obesity, Body Fat Distribution, Weight Loss and Weight Cycling on Serum Pesticide Concentrations

OBJECTIVE

Preliminary studies suggest pesticides may be linked to increased cancer risk. Since most pesticides are lipophilic and stored within adipose tissue, serum levels of organochlorines are affected not only by environmental exposures, but also by factors related to lipid turnover and storage. Our objective was to investigate whether serum organochlorines are influenced by weight loss, body fat distribution, and weight cycling.

METHODS

Ten overweight women were recruited upon entry into a weight loss program and surveyed regarding weight history, childbearing/lactation, and exposure to environmental contaminants. Anthropometric measures and phlebotomy were conducted at baseline and at four weeks (mean weight loss=5.1 kg). Serum was analyzed for 19 common polychlorinated pesticides and metabolites and 10 PCB congeners.

RESULTS

Organochlorine levels were not significantly affected by weight loss nor associated with body mass index (BMI). Strong positive correlations were noted between levels of DDE/DDT and age (DDE β=0.6986/p=0.0246/DDT β=0.6536/p=0.0404) and between DDE/DDT and waist-to-hip ratio (WHR) (DDE β=0.4356/p=0.0447/DDT β=0.8108/p=0.0044). Trends were noted for decreased levels of DDT in women who reported more episodes of weight cycling.

CONCLUSION

Serum organochlorine levels may be affected not only by age, but also factors related to lipid turnover (i.e., episodes of weight cycling and WHR), and warrants further study.

Weight cycling and the risk of type 2 diabetes in the EPIC-Germany cohort

AIMS/HYPOTHESIS

Studies on weight cycling and the risk of type 2 diabetes have revealed inconsistent results, possibly due to differences in the definition of weight fluctuations. Here, we investigated whether weight cycling during adulthood is related to diabetes risk in a large cohort study, using a complementary approach to define patterns of weight development.

METHODS

Weight cycling, weight loss and weight gain were defined (1) a priori, using distinct categories, and (2) by functional principal component analysis (FPCA) to capture weight patterns in greater detail. Associations of weight cycling, weight loss and weight gain with the risk of type 2 diabetes were evaluated by Cox regression models.

RESULTS

A priori defined weight cycling was associated with increased diabetes risk, compared with stable weight (HR 1.36 [95% CI 1.09, 1.68]). No significant association between FPCA-derived weight cycling and risk of diabetes was observed after adjustment for concurrent weight patterns (HR 1.19 [95% CI 0.89, 1.60]). Subgroup analyses showed that FPCA-derived weight cycling during net weight gain was associated with a higher risk of diabetes (HR 1.68 [95% CI 1.14, 2.48]). A priori defined weight gain (HR 2.08 [95% CI 1.60, 2.70]) was more clearly related to the risk of diabetes than FPCA-derived weight gain (HR 1.20 [95% CI 0.95, 1.51]), while no significant associations were observed for weight loss.

CONCLUSIONS/INTERPRETATION

Overall, weight cycling may not be an independent risk factor for type 2 diabetes when accounting for concurrent patterns of weight development. However, weight cycling may pose a stronger risk of diabetes than non-cycling during net weight gain.

Body Weight Dynamics Following Intentional Weight Loss and Physical Performance: The Look AHEAD Movement and Memory Study

Objective

The aim of this study was to explore the impact of body weight change following intentional weight loss on measures of physical performance in adults with diabetes.

Design and methods

Four hundred fifty individuals with type 2 diabetes (age, 59.0 ± 6.9 years; body mass index, 35.5 ± 5.9 kg/m²) who participated in the Look AHEAD Movement and Memory Study and lost weight 1 year after being randomized to an intensive lifestyle intervention were assessed. Body weight was measured annually, and participants were categorized as continued losers/maintainers, regainers, or cyclers based on a ±5% annual change in weight. Objective measures of physical performance were measured at the year 8/9 visit.

Results

Forty‐four percent, 38% and 18% of participants were classified as regainers, cyclers, and continued losers/maintainers, respectively. In women, weight cycling and regain were associated with worse follow‐up expanded physical performance battery score (1.46 ± 0.07 and 1.48 ± 0.07 vs. 1.63 ± 0.07, both p ≤ 0.02) and slower 20‐m walking speed (1.10 ± 0.04 and 1.08 ± 0.04 vs. 1.17 ± 0.04 m/s, both p < 0.05) compared with continued or maintained weight loss. Male cyclers presented with weaker grip strength compared with regainers or continued losers/maintainers (30.12 ± 2.21 vs. 34.46 ± 2.04 and 37.39 ± 2.26 kg; both p < 0.01).

Conclusions

Weight cycling and regain following intentional weight loss in older adults with diabetes were associated with worse physical function in women and grip strength in men.

Adaptive Thermogenesis in Resistance to Obesity Therapies: Issues in Quantifying Thrifty Energy Expenditure Phenotypes in Humans

Dieting and exercise are likely to remain the core approaches in the management of obesity in the foreseeable future despite their well-documented failures for achieving long-term weight loss. Explanations for such poor prognosis are centered on patient's self-regulatory failure and lack of compliance to the prescribed diet or exercise regimen. While a role for physiological adaptations leading to diminished rates of heat production has also been advocated, there are considerable uncertainties about the quantitative importance of such regulated heat production (i.e., adaptive thermogenesis) to the less-than-expected weight loss and ease for weight regain. This paper first reviews the most compelling evidence of what is often considered as weight loss-induced adaptive thermogenesis in various compartments of daily energy expenditure. It then discusses the major limitations and issues in quantifying such thrifty energy expenditure phenotypes and underscores the plausibility of diminished core temperature as a thrifty metabolic trait in resistance to weight loss. Although an accurate quantification of adaptive thermogenesis will have to await the applications of deep body composition phenotyping and better discrimination of physical activity energy expenditures, the magnitude of diminished energy expenditure in response to weight loss in certain individuals is large enough to support the concept that adaptive thermogenesis contribute importantly to their resistance to obesity therapies.

A cross-sectional study

OBJECTIVE

Weight cycling is a prevalent phenomenon in obese individuals. There is evidence that temperamental factors are associated with obesity and subgroups among the obese have been identified based on reactive and regulative aspects of temperament.

METHODS

We aimed at investigating the association between reactive and regulative aspects of temperament and severe weight cycling in overweight and obese individuals of a representative German population sample (n = 923). Participants completed questionnaires assessing weight parameters including BMI and weight cycling, sensitivity to punishment and to reward (BIS/BAS scales), self-regulatory abilities (effortful control scale), depressive symptoms, and binge eating.

RESULTS

Severe weight cycling was more common in women, and was associated with higher reward sensitivity, higher current and maximum-ever BMI, higher weight suppression, more depressive symptoms, and a higher prevalence of binge eating. In contrast, sensitivity to punishment and effortful control were not associated with severe weight cycling. Also, the interaction between sensitivity to reward and effortful control did not predict weight cycling.

DISCUSSION

Higher reward sensitivity might not only render individuals vulnerable for weight regain but might also be associated with a higher frequency of weight loss attempts due to the putative rewarding properties of the initial success in weight loss at the early stages of a diet. Temperamental factors should be considered in the treatment of obesity.

Weight cycling in bipolar disorder

BACKGROUND

An association between excess weight and/or weight fluctuations and cardiovascular morbidity and mortality is amply documented. Individuals with bipolar disorder (BD) are differentially affected by overweight/obesity, chaotic eating patterns (e.g., binge eating), as well as cardiovascular morbidity and mortality. Weight cycling (WCYC) is defined as a pattern of repetitive weight loss and gain.

METHODS

We sought to determine the relationship between course of illness and BD and WCYC retrospectively as well whether these co-occurring phenotypes identify a biologically distinct subpopulation on the basis of having a unique inflammatory biomarker/biosignature profile. Sociodemographic, clinical, and inflammatory markers were gathered from a well-characterized cohort of actual euthymic adults with BD (n=101) and a healthy control group (n=48).

RESULTS

Individuals with BD with a history of WCYC were provided evidence of a greater frequency of prior episodes (i.e., both manic and depressed), as well as of significantly higher levels of circulating IL-6 concentrations when compared to non-WCYC individuals with BD. The association persisted after adjusting for relevant covariates (e.g., BMI, age, number of prior episodes).

LIMITATIONS

Include the small control group, differing medication status and that all data relies on personal information. Nevertheless we tried to verify all data as far as clinical disclosure was available.

CONCLUSION

The results of this study indicate that adults with BD excessive in weight are not only more susceptible to a relapse-prone course of illness, but also are more likely to present with WCYC. The finding of elevated pro-inflammatory cytokines in this subpopulation may identify a separate subpopulation with greater susceptibility to cardiovascular disease. The overarching aim of personalized treatment and preventive strategies in BD begins with appropriate, empirically supported patient stratification. Our results provide preliminary support for stratifying BD cardiovascular risk on the basis of anthropometrics and WCYC.

Long-term multiple intragastric balloon treatment--a new strategy to treat morbid obese patients refusing surgery: prospective 6-year follow-up study. Surg Obes Relat Dis. 2014;10:307-311. [PMID: 24462306 DOI: 10.1016/j.soard.2013.10.013]

BACKGROUND

Morbid obesity is an increasing health problem. Dietary intervention often fails in the medium to long term, and surgery is the gold standard. Intragastric balloon is a valuable treatment in the short-term, and multiple balloon treatment has been shown to be effective in the medium term. The aim of this study was to investigate the efficacy of multiple balloon treatment in the long-term (6 years) in terms of weight loss, influence on co-morbidities, and quality of life in patients refusing surgery.

METHODS

Eighty-three patients with body mass index (BMI)>40, good candidates for surgery but refusing it, were enrolled in a clinical treatment protocol involving multiple intragastric balloon placement. After removing the first balloon, a second balloon was placed when the patients had regained ≥ 50% of the weight loss achieved with previous balloon. Weight, co-morbidities parameters, and quality of life test were recorded during a follow-up of 72 months.

RESULTS

All patients experienced a second balloon placement; 22.2% had a third device placed and 1 patient had a fourth device placed. At 76 months follow-up, mean BMI was 37.6 kg/m(2) (P < .001); weight cycling periods were observed. Significant difference was recorded in the presence of co-morbidities at baseline (80% of the patients) and follow-up (30%) (P = .02). Quality of life test in the follow-up indicated better scores than those at baseline (P < . .001).

CONCLUSION

Despite the weight cycling, in patients refusing surgery, multiple intragastric balloon is the recommended treatment, allowing the patients to achieve a good weight loss, better control of co-morbidities, and better quality of life than at baseline.

Consequences of Weight Cycling: An Increase in Disease Risk?

Research indicates that weight cycling, or "yo-yo dieting" is a common occurrence in overweight and obese populations. The long term negative health consequences of weight cycling are debated and it is unclear whether or not this weight change pattern poses a greater disease risk compared to obesity maintenance. This review discusses the prevalence of weight cycling and physiological alterations occurring during weight loss that promotes weight regain. We also discuss the effect weight regain has upon adipose tissue in terms of rate and type of accumulation. Also within this review are discussions surrounding the previously published literature based upon human and rodent research. We focus on previous limitations and difference in experimental design that have perhaps resulted in mixed findings concerning independent effects of weight cycling on health parameters. The final purpose of this review is to discuss future directions in evaluating the pro-inflammatory response to weight cycling in order to compare the disease risk compared to obesity maintenance.