Disordered Eating and Recurrent Weight Gain After MBS

February 20, 2026 updated by: Seher Şen, Medipol University

Disordered Eating, Emotional Eating, and Nutritional Status in Patients With Recurrent Weight Gain After Metabolic and Bariatric Surgery

Obesity represents an increasingly serious public health problem worldwide. According to the World Health Organization, one in eight individuals globally is affected by obesity. Bariatric surgery (BS) is recognized as the most effective treatment for severe obesity and has been shown to significantly improve obesity-related comorbidities. However, despite initially successful surgical outcomes, a substantial proportion of patients experience insufficient weight loss (IWL) or weight regain (WR) after surgery.

Previous studies have identified multiple factors associated with post-bariatric IWL and WR, including older age, low socioeconomic status, higher baseline body mass index (particularly preoperative BMI >50 kg/m²), type of surgical procedure, hormonal mechanisms, poor adherence to postoperative dietary recommendations, maladaptive eating behaviors, insufficient physical activity, and the presence of psychiatric comorbidities. Among these, behavioral factors appear to play a particularly critical role. Irregular eating patterns such as loss of control eating, maladaptive behaviors such as grazing, non-adherence to dietary guidelines, and a return to preoperative eating habits are frequently associated with weight regain. Additionally, physiological mechanisms, including increased appetite, food cravings, and altered hormonal regulation of energy intake, may further contribute to this process.

Grazing behavior-defined as repetitive consumption of small amounts of food accompanied by a sense of loss of control-has been consistently associated with poorer weight outcomes after bariatric surgery. A large meta-analysis reported grazing prevalence rates between 16.6% and 46.6%, with weight regain observed in nearly half of post-bariatric patients. Moreover, lack of structured nutritional follow-up has been shown to significantly increase the risk of weight regain. Neurobehavioral changes also occur after surgery: while appetite and responsiveness to palatable foods typically decrease during the first postoperative year, these effects often diminish over time, with hunger, cravings, and portion sizes gradually increasing in some individuals.

Long-term weight regain has been closely linked to disordered eating behaviors, including emotional eating, binge eating, compulsive eating, food addiction, and loss of control eating. Recent studies have demonstrated significant associations between weight regain and binge eating disorder, eating disinhibition, and impulsivity. Qualitative research further highlights that many patients struggle to manage emotional eating and require ongoing psychological and dietary support following surgery.

Despite growing evidence emphasizing the behavioral and psychological components of post-bariatric outcomes, comprehensive studies that simultaneously evaluate nutritional status, eating disorders, and emotional factors in individuals experiencing IWL or WR remain limited. Therefore, the present study aims to assess nutritional status, eating disorder symptoms, and emotional factors in individuals who experience insufficient weight loss or weight regain after bariatric surgery. By integrating anthropometric, nutritional, behavioral, and emotional assessments within the same sample, this study seeks to provide a multidimensional perspective and contribute to the development of more effective multidisciplinary follow-up and psychodietetic interventions.

Study Overview

Status

Active, not recruiting

Conditions

Intervention / Treatment

Study Type

Observational

Enrollment (Actual)

49

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Sampling Method

Non-Probability Sample

Study Population

Adults aged 18-65 years who had undergone metabolic bariatric surgery at least 5 years previously and demonstrated suboptimal clinical response (SCR) or recurrent weight gain (RWG) were included. Participants were evaluated during a single follow-up visit.

Description

Inclusion Criteria:

  • Adults aged 18-65 years
  • History of metabolic bariatric surgery
  • At least 5 years post-surgery
  • Individuals presenting either:

recurrent weight gain after initial successful weight loss, or insufficient weight loss defined as nadir percent total weight loss (%TWL nadir) <20%.

Recurrent weight gain (RWG) was defined according to IFSO consensus recommendations. RWG (%) was calculated as:

RWG (%) = (weight regained / maximum weight loss) × 100

Participants were categorized using a cut-off value of 30% (RWG ≥30% vs. <30%).

Exclusion Criteria:

  • Pregnant or breastfeeding individuals
  • Acute illness or active infection
  • Medical conditions limiting study safety (e.g., cancer, type 1 diabetes, renal or hepatic failure, recent stroke or myocardial infarction, nephrolithiasis, substance abuse, eating disorders, severe depression or other major psychiatric disorders, inflammatory bowel disease, neoplasia, cardiac arrhythmia, heart failure, respiratory failure, or systemic corticosteroid therapy)
  • Professional athletes

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in body weight
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Change in body weight measured using a calibrated, stationary scale with participants in light clothing and no shoes. Measurements were performed according to standard anthropometric practice to ensure accuracy, with participants instructed to remove heavy garments and accessories before weighing.
Postoperative 5-8 years (60-96 months), single assessment
Change in body mass index (BMI)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Change in body mass index calculated from measured body weight and height at each assessment
Postoperative 5-8 years (60-96 months), single assessment
Change in body fat percentage
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Body fat percentage was assessed using bioelectrical impedance analysis (BIA) with a Tanita MC-780 MA analyzer (Tanita Corp., Japan) in accordance with European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines. Measurements were performed under standardized conditions with participants wearing light clothing and barefoot.
Postoperative 5-8 years (60-96 months), single assessment
Change in waist circumference
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Change in waist circumference measured using standardized anthropometric procedures.
Postoperative 5-8 years (60-96 months), single assessment
Outcome: Percent total weight loss at nadir (%TWL nadir)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment

Percent total weight loss at nadir was calculated as:

%TWL = (preoperative weight - postoperative nadir weight) / preoperative weight × 100.

Postoperative nadir weight was defined as the lowest body weight achieved after surgery.
Postoperative 5-8 years (60-96 months), single assessment
Percent total weight loss at current follow-up (%TWL current)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment

Current percent total weight loss was calculated as:

%TWL = (preoperative weight - current body weight) / preoperative weight × 100.
Postoperative 5-8 years (60-96 months), single assessment
Relative weight regain (%RWG)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment

Relative weight regain was calculated according to consensus recommendations as:

RWG (%) = (weight regained / maximum weight loss) × 100. Participants were categorized based on a cut-off value of 30% (RWG ≥30% vs. <30%).
Postoperative 5-8 years (60-96 months), single assessment
Eating disorder symptoms assessed by Eating Disorder Examination Questionnaire (EDE-Q)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Eating disorder symptoms were assessed using the Eating Disorder Examination Questionnaire (EDE-Q), a 28-item self-report instrument developed by Fairburn et al. The validated Turkish version was used. The questionnaire includes subscales assessing restraint, binge eating, shape concern, eating concern, and weight concern. Items (except binge eating frequency items) are rated on a 0-6 Likert scale, with higher scores indicating greater severity of eating disorder psychopathology. Permission for scale use was obtained.
Postoperative 5-8 years (60-96 months), single assessment
Emotional eating behavior assessed by Emotional Eater Questionnaire (EEQ)
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Emotional eating behavior was assessed using the Emotional Eater Questionnaire (EEQ), a 10-item self-report instrument developed by Garaulet et al. The validated Turkish version was used. The scale evaluates loss of eating control, food preference tendency, and guilt related to eating. Items are scored on a 0-3 Likert scale, with higher scores indicating greater emotional eating behavior. Permission for scale use was obtained.
Postoperative 5-8 years (60-96 months), single assessment

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Dietary intake from 3-day food record
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Dietary intake was assessed using a 3-day food record including one weekend day. Portion sizes were estimated using a standardized food photograph catalog, and standard recipes were consulted when needed. Macro- and micronutrient intake was analyzed using Nutrition Information Systems software (BEBIS 9, Version 9.0, Istanbul, Turkey).
Postoperative 5-8 years (60-96 months), single assessment
Glycemic parameters
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Fasting glucose metabolism markers including fasting blood glucose, HbA1c, and HOMA-IR were recorded after a minimum of 8 hours of fasting.
Postoperative 5-8 years (60-96 months), single assessment
Lipid profile
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Serum lipid parameters including HDL cholesterol, LDL cholesterol, total cholesterol, and triglycerides were recorded after a minimum of 8 hours of fasting.
Postoperative 5-8 years (60-96 months), single assessment
Hematological and iron status parameters
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Hemoglobin, hematocrit, ferritin, and serum iron levels were recorded following at least 8 hours of fasting.
Postoperative 5-8 years (60-96 months), single assessment
Vitamin status parameters
Time Frame: Postoperative 5-8 years (60-96 months), single assessment
Serum vitamin B12 and folic acid levels were recorded after a minimum of 8 hours of fasting.
Postoperative 5-8 years (60-96 months), single assessment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medipol University

Collaborators

Mudanya University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

January 2, 2025

Primary Completion (Actual)

September 10, 2025

Study Completion (Estimated)

March 5, 2026

Study Registration Dates

First Submitted

February 16, 2026

First Submitted That Met QC Criteria

February 20, 2026

First Posted (Actual)

February 25, 2026

Study Record Updates

Last Update Posted (Actual)

February 25, 2026

Last Update Submitted That Met QC Criteria

February 20, 2026

Last Verified

February 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • MUDU-SBE-SS-03

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Individual participant data will not be shared due to privacy and confidentiality protections. The dataset contains sensitive clinical information that could potentially allow participant identification. Data will be reported only in aggregated and de-identified form in publications.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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