Methodological issues in weight cycling

Obesity, obesities and gastrointestinal cancers

Obesity has been recognized to be increasing globally and is designated a disease with adverse consequences requiring early detection and appropriate care. In addition to being related to metabolic syndrome disorders such as type 2 diabetes, hypertension, stroke, and premature coronary artery disease. Obesity is also etiologically linked to several cancers. The non-gastrointestinal cancers are breast, uterus, kidneys, ovaries, thyroid, meningioma, and thyroid. Gastrointestinal (GI) cancers are adenocarcinoma of the esophagus, liver, pancreas, gallbladder, and colorectal. The brighter side of the problem is that being overweight and obese and cigarette smoking are mostly preventable causes of cancers. Epidemiology and clinical studies have revealed that obesity is heterogeneous in clinical manifestations. In clinical practice, BMI is calculated by dividing a person's weight in kilograms by the square of the person's height in square meters (kg/m2). A BMI above 30 kg/m2 (defining obesity in many guidelines) is considered obesity. However, obesity is heterogeneous. There are subdivisions for obesity, and not all obesities are equally pathogenic. Adipose tissue, in particular, visceral adipose tissue (VAT), is endocrine and abdominal obesity (a surrogate for VAT) is evaluated by waist-hip measurements or just waist measures. Visceral Obesity, through several hormonal mechanisms, induces a low-grade chronic inflammatory state, insulin resistance, components of metabolic syndrome, and cancers. Metabolically obese, normal-weight (MONW) individuals in several Asian countries may have BMI below normal levels to diagnose obesity but suffer from many obesity-related complications. Conversely, some people have high BMI but are generally healthy with no features of metabolic syndrome. Many clinicians advise weight loss by dieting and exercise to metabolically healthy obese with large body habitus than to individuals with metabolic obesity but normal BMI. The GI cancers (esophagus, pancreas, gallbladder, liver, and colorectal) are individually discussed, emphasizing the incidence, possible pathogenesis, and preventive measures. From 2005 to 2014, most cancers associated with overweight and Obesity increased in the United States, while cancers related to other factors decreased. The standard recommendation is to offer or refer adults with a body mass index (BMI) of 30 or more to intensive, multicomponent behavioral interventions. However, the clinicians have to go beyond. They should critically evaluate BMI with due consideration for ethnicity, body habitus, and other factors that influence the type of obesity and obesity-related risks. In 2001, the Surgeon General's ``Call to Action to Prevent and Decrease Overweight and Obesity'' identified obesity as a critical public health priority for the United States. At government levels reducing obesity requires policy changes that improve the food and physical activity for all. However, implementing some policies with the most significant potential benefit to public health is politically tricky. The primary care physician, as well as subspecialists, should identify overweight and Obesity based on all the variable factors in the diagnosis. The medical community should address the prevention of overweight and Obesity as an essential part of medical care as much as vaccination in preventing infectious diseases at all levels- from childhood, to adolescence, and adults.

The effect of weight regain on cardiometabolic health in children with obesity: A systematic review of clinical studies

AIMS

Children with obesity are treated by a lifestyle intervention to obtain weight loss. Nevertheless, weight regain often occurs. This systematic review examines the effect of weight regain on cardiometabolic health and summarizes these results in the metabolic syndrome prevalence as integrated endpoint.

DATA SYNTHESIS

A literature search was performed in PubMed and Web of Science. Studies were selected if they included participants aged <18 years with obesity and presented data before and after weight loss and after weight regain hereby reporting minimally 1 cardiovascular risk factor at every assessment. After screening, nine articles remained. Generally, the diastolic BP re-increased after weight regain, whereas for systolic BP a sustained result for 6 months was reported with an increase during longer follow-up. No significant changes in fasting glucose were reported after weight regain compared to baseline. Regarding triglycerides, a complete weight regain re-increased the lowered values to baseline, whereas a partial regain resulted in a sustained decrease in triglycerides in 2 studies and an increase to intermediate levels in 1 paper. HDL-cholesterol only rose several months after initiating treatment. Hs-CRP remained lowered for a longer period than the moment where the weight loss nadir was achieved.

CONCLUSION

Research on weight regain and cardiometabolic health in children with obesity is scarce. No convincing evidence was found for a worsening of the cardiometabolic profile after weight regain. Some benefits even persisted despite weight recovery. Subsequently, the metabolic syndrome prevalence seems temporarily lowered after weight loss, despite weight regain.

The effect of overtraining on serum leptin levels in women national wrestlers

Purpose: Weight control and weight loss during the periods of wrestling competitions are attached great importance -in order to be successful in wrestling. Leptin hormone level is known to play an important role in the control of body weight. For this reason, the purpose of this study was to investigate the effect of substantial weight loss on serum leptin levels of women wrestlers during competition periods. Material and Methods: Twenty-five women wrestlers who trained for 2015 European Championship from Turkish National Wrestling Team and 26 sedentary women were recruited voluntarily for this study. Serum leptin levels of wrestlers in the experimental group and sedentary women in the control group were measured after overnight fasting before and after 21 days training camp of 2015 European Championship. Results. Statistically significant difference was found in the direction of decrease in body weight, body mass index (BMI), glucose, insulin, cholesterol, triglyceride, LD, VLDL and leptin parameters and increase in HDL parameters before and after training camp in the experimental group ( p < .05 ). There was a statistically significant difference in leptin levels between the control group and women wrestlers ( p < .05 ). There was also a statistically significant difference in leptin levels of wrestlers before and after training camp ( p < .05 ). Conclusion. As a result, the data obtained in the study indicate that intense wrestling trainings in camping period brought about weight loss and decreased leptin levels.

Psychological status and weight variability over eight years: Results from Look AHEAD

OBJECTIVE

Cross-sectional studies suggest an association between weight cycling and psychological status. Although this is often interpreted as suggesting that weight cycles "cause" psychological distress, the relationship could be bidirectional. This study provides a prospective analysis of the bidirectional association between weight variability and psychological status over an 8-year period in overweight/obese adults with Type 2 diabetes.

METHOD

Data were from the first 8 years of Look AHEAD, a randomized controlled trial comparing health outcomes in individuals with Type 2 diabetes assigned to an intensive lifestyle intervention designed to produce weight loss or a diabetes education and support control group. Psychological status (mental health, depressive symptoms, binge eating) was assessed via surveys and were examined in relation to weight variability at both baseline and year 8. Weight variability was derived from 8 possible annual measurements from participants who had a minimum of 3 consecutive body weight measurements (N = 4,774) and operationalized as the number of year-to-year cycles and the coefficient of variation across all available weight measurements.

RESULTS

Controlling for study group, higher baseline scores on mental health (Short Form-36 Mental Component Summary) and lower levels of depressive symptomatology (Beck Depression Inventory) and binge eating (Questionnaire on Eating and Weight Patterns) were associated with significantly less subsequent weight variability. The prospective association between weight variability and psychological status at year 8 was less robust.

CONCLUSIONS

These results suggest that the cross-sectional relationship between weight variability and psychological status is due primarily to poorer psychological function preceding greater weight instability. (PsycINFO Database Record

Impact of weight cycling on risk of morbidity and mortality

Unintentional weight gain is commonly observed in adult humans, often provoking intentional weight loss attempts followed by unintentional weight regain. This episodic variation in body weight over a period of time has been referred to as 'weight cycling'. Over the last two decades, weight cycling has been associated with a number of morbid health conditions and increased mortality. This article provides a comprehensive evaluation of recent weight-cycling evidence, looks to understand design differences between studies and study outcomes, assesses the need for further research on particular health outcomes, and proposes alternative methodologies that will bridge the needs and capabilities of research. Searches were conducted per PRISMA guidelines. Articles on weight cycling in the literature were initially identified using search strings in PubMed. Eligibility assessment of the remaining articles was performed independently by three reviewers to identify publications that presented direct evidence. Twenty human studies (in addition to seven animal studies) were selected and retained; 12 accounted for the intentionality of weight loss. Although weight regain following successful weight loss remains one of the most challenging aspects of body-weight regulation, evidence for an adverse effect of weight cycling appears sparse, if it exists at all.

Predictors of weight loss maintenance following an insurance-sponsored weight management program

Intentional weight loss among overweight and obese adults (body mass index ≥ 25 kg/m(2)) is associated with numerous health benefits, but weight loss maintenance (WLM) following participation in weight management programming has proven to be elusive. Many individuals attempting to lose weight join formal programs, especially women, but these programs vary widely in focus, as do postprogram weight regain results. We surveyed 2,106 former participants in a community-based, insurance-sponsored weight management program in the United States to identify the pre, during, and post-intervention behavioral and psychosocial factors that lead to successful WLM. Of 835 survey respondents (39.6% response rate), 450 met criteria for inclusion in this study. Logistic regression analyses suggest that interventionists should assess and discuss weight loss and behavior change perceptions early in a program. However, in developing maintenance plans later in a program, attention should shift to behaviors, such as weekly weighing, limiting snacking in the evening, limiting portion sizes, and being physically active every day.

No effect of weight cycling on the post-career BMI of weight class elite athletes

Background

Repetitions of pre-competition weight-loss diets done by athletes participating in weight class sports can be regarded as periods of weight cycling. The aim of the present study is to identify the long term post-career (22 years) evolutionary profile of athletes’ BMI after such weight cycling.

Methods

One hundred and thirty-six retired French athletes who participated in major international competitions in weight class sports (rowers, wrestlers, boxers, and judokas) were included. Former and current body mass, height, dietary characteristics during the career (annual frequency, amount of weight lost), current physical activity, and answers on the eating-attitude test were collected by phone interview (consistency was tested by comparison with measured weight). We performed ANOVA tests for comparison between groups (sport, dieting), post-hoc tests (Bonferroni test) to identify differences within groups. BMI’s changes were treated using a mixed model.

Results

The recorded weight changes did not depend upon time since retirement. Between 18 y and 50 y, athletes’ BMI increased by 3.2 kg/m² compared to the 4.2 kg/m² increase in the general population. This increase was independent of the number of diets during the career. Retired athletes declared a mean weekly physical activity of 4.8 h ± 4.3. The eating-attitude test showed low scores for all sports without any correlation to diet characteristics.

Conclusion

Weight cycling during an athletic career does not induce a massive weight gain after retirement, probably due to the high level of physical activity still practiced after retirement by these athletes.

Weight cycling and cancer: weighing the evidence of intermittent caloric restriction and cancer risk

Overweight and obese individuals frequently restrict caloric intake to lose weight. The resultant weight loss, however, typically is followed by an equal or greater weight gain, a phenomenon called weight cycling. Most attention to weight cycling has focused on identifying its detrimental effects, but preclinical experiments indicating that intermittent caloric restriction or fasting can reduce cancer risk have raised interest in potential benefits of weight cycling. Although hypothesized adverse effects of weight cycling on energy metabolism remain largely unsubstantiated, there is also a lack of epidemiologic evidence that intentional weight loss followed by regain of weight affects chronic-disease risk. In the limited studies of weight cycling and cancer, no independent effect on postmenopausal breast cancer but a modest enhancement of risk for renal cell carcinoma, endometrial cancer, and non-Hodgkin's lymphoma have been reported. An effect of either intermittent caloric restriction or fasting in protecting against cancer is not supported by the majority of rodent carcinogenesis experiments. Collectively, the data argue against weight cycling and indicate that the objective of energy balance-based approaches to reduce cancer risk should be to strive to prevent adult weight gain and maintain body weight within the normal range defined by body mass index.

Essverhalten und psychosoziale Belastung von Personen mit hoher und niedriger wahrgenommener Diäthäufigkeit

Zusammenfassung. In der vorliegenden Studie wurden Personen, die angaben, bereits häufig Diäten durchgeführt zu haben, und Personen, die angaben, selten oder noch nie diätiert zu haben, bezüglich ihrer aktuellen Essgewohnheiten und ihrer psychosozialen Belastung verglichen. Die Stichprobe umfasste 48 Männer und 46 Frauen mit einem durchschnittlichen Alter von 28.6 Jahren, die eingeteilt wurden in Personen, die angaben, bereits häufig (mindestens 4-mal; n = 24) vs. selten oder nie (0-3-mal; n = 70) Schlankheitsdiäten durchgeführt zu haben. Die aktuellen Essgewohnheiten beider Gruppen wurden verglichen anhand des “Fragebogens zum Essverhalten“ (FEV) und des “Inventars zum Essverhalten und Gewichtsproblemen“ (IEG). Die psychosoziale Belastung wurde erfasst mit dem “Kurzfragebogen zur aktuellen Beanspruchung“ (KAB) und dem “Trierer Inventar zur Erfassung von chronischem Stress“ (TICS). Personen mit häufigen Diäten in der Vorgeschichte hatten signifikant höhere Werte auf den FEV-Skalen “gezügeltes Essen“, “Störbarkeit des Essverhaltens“ und “erlebte Hungergefühle“. Dieselben Unterschiede fanden sich für die IEG-Skalen “Stärke und Auslösbarkeit des Essverhaltens“, “sozial situative Auslöser für Mehressen“, und “Essen als Mittel gegen emotionale Belastung“. Auf psychosozialer Ebene wiesen Personen, die häufige Diäten berichten, eine höhere aktuelle Beanspruchung auf und zeigten ein höheres Ausmaß an sozialer Überlastung, Überforderung sowie Besorgnisneigung. Die Ergebnisse werden kritisch diskutiert; darüber hinaus werden gesundheitspsychologische Schlussfolgerungen angerissen.

Eating self-efficacy and weight cycling: a prospective clinical study

Previous retrospective studies have not identified global psychosocial consequences of weight cycling. These lack of findings may be due to limitations associated with retrospective research or with using general psychological measures rather than weight-specific measures. This prospective study examined changes in a weight-specific measure, eating self-efficacy, using an obese clinical population who returned to a multidisciplinary weight management program subsequent to weight regain. Subjects did not demonstrate any change in eating self-efficacy despite experiencing weight loss and then weight regain. Individuals returning for treatment may be a select population, thus suggesting that there may not be negative psychological effects of weight cycling for all individuals. Implications for further research are discussed.

Psychological effects of weight cycling in obese persons: a review and research agenda

This review summarizes studies on the psychological effects of weight cycling (i.e., weight loss and regain) in obese persons and proposes an agenda for future research on this topic. Among general psychological constructs, the current literature suggests that weight cycling is not associated with depression, other psychopathology, or depressogenic cognitive styles. Weight cycling is associated with decreased perceptions of health and well-being, although the clinical significance of this relationship is uncertain. Among weight- and eating-related constructs, weight cycling does not appear to be related to restraint, hunger, or personality traits associated with eating disorders. Weight cycling, however, does appear to be associated with clinically significant reductions in eating self-efficacy and weak but consistent increases in binge eating severity. Definitive conclusions about the presence or absence of the psychological consequences of weight cycling are premature, given the small number of studies, as well as a variety of methodological and interpretive concerns. A new generation of research is necessary to determine the extent and nature of the psychological sequelae of weight cycling.