Lifestyle Intervention for Obesity and Eating Disorder Prevention in Transgender Adolescents

Lifestyle Intervention to Prevent Obesity and Eating Disorders in Transgender and Gender-Diverse Adolescents: A Randomized Controlled Trial

Transgender and gender-diverse adolescents are at increased risk for obesity, disordered eating behaviors, body dissatisfaction, and reduced quality of life due to minority stress and structural inequities. However, no structured lifestyle interventions specifically tailored to this population have been developed.

This randomized controlled trial aims to evaluate the effectiveness of a 6-month interdisciplinary lifestyle intervention designed to prevent obesity and eating disorders in transgender and gender-diverse adolescents aged 10-14 years. Participants will be randomized (1:1) to either an intervention group receiving monthly group sessions (for adolescents and caregivers separately) and weekly supportive messages, or a control group receiving standard outpatient care and general health recommendations.

The primary outcome is quality of life measured by the WHOQOL-BREF. Secondary outcomes include eating disorder symptoms, body image, diet quality, physical activity levels, sedentary behavior, body composition, and anthropometric measures.

Study Overview

• Status: Recruiting
• Conditions: Body Image Disturbance; Eating Disorders; Obesity & Overweight; Gender Diverse Populations
• Intervention / Treatment: Behavioral: TransForm Health Program

Detailed Description

This study is a parallel-group randomized controlled trial conducted at the Lifestyle Medicine Center, Faculty of Medicine, University of São Paulo (FMUSP), Brazil.

Participants will be recruited from the Gender Identity and Sexual Orientation Outpatient Clinic (AMTIGOS) at the Institute of Psychiatry, Hospital das Clínicas, University of São Paulo. Eligible transgender and gender-diverse adolescents aged 10 to 14 years receiving care at AMTIGOS will be invited to participate.

After baseline assessments, participants will be randomly assigned (1:1), in blocks of six, to either:

1. an interdisciplinary lifestyle intervention plus usual outpatient care; or
2. usual outpatient care plus a single session of general health recommendations.

The 6-month intervention is grounded in Social Cognitive Theory and incorporates gender-affirmative principles and an intersectional framework. The intervention includes:

• Monthly group sessions for adolescents
• Monthly educational group sessions for caregivers
• Weekly reinforcement messages

The program focuses on promoting healthy eating behaviors, increasing physical activity, reducing sedentary behavior, preventing unhealthy weight-control practices, and fostering positive body image and body appreciation.

The control group will receive standard outpatient follow-up at AMTIGOS and a single individual session including general recommendations regarding healthy eating, physical activity, body acceptance, and avoidance of unhealthy weight-control behaviors.

Outcomes will be assessed at baseline and after 6 months. The primary outcome is quality of life measured by the WHOQOL-BREF. Secondary outcomes include eating disorder symptoms, body image, dietary quality, physical activity, sedentary behavior, body composition, and anthropometric measures.

• Study Type: Interventional
• Enrollment (Estimated): 24
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Bruno Gualano, PhD; Phone Number: +551130618789; Email: gualano@usp.br
• Study Contact Backup: Name: Bruna Caruso Mazzolani, PhD; Email: bruna.mazzolani@usp.br

Study Locations

• Brazil
  • São Paulo
    • São Paulo, São Paulo, Brazil, 05403010
      • Recruiting
      • Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo
      • Contact: Bruno Gualano, PhD; Phone Number: +551126618022; Email: gualano@usp.br

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Aged 10-14 years
• Self-identified as transgender or gender-diverse

Exclusion Criteria:

• Current diagnosis of eating disorder requiring specialized treatment
• Severe psychiatric instability
• Cognitive impairment limiting participation

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: TransForm Health group; A group intervention focused on promoting health lifestyle behaviors for preventing obesity and eating disorders in transgender and gender-diverse adolescents.	Behavioral: TransForm Health Program; A 6-month structured intervention including monthly adolescent group sessions, monthly caregiver sessions, monthly individual goal-setting meetings, and weekly reinforcement messages focused on healthy eating, physical activity, body appreciation, and prevention of unhealthy weight-control behaviors.
No Intervention: Control group; Usual care and general health lifestyle behaviors recommendations.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Quality of Life (World Health Organization Quality of Life - BREF)	Quality of life will be measured using the World Health Organization Quality of Life - BREF (WHOQOL-BREF) questionnaire. The WHOQOL-BREF consists of 26 items covering four domains (physical health, psychological health, social relationships, and environment). Domain scores are transformed to a scale ranging from 0 to 100, with higher scores indicating better quality of life.	Baseline and 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body fat	Body fat will be measured by dual-energy X-ray absorptiometry (DEXA).	Baseline and 6 months
Muscle mass	Muscle mass will be measured by dual-energy X-ray absorptiometry (DEXA).	Baseline and 6 months
Bone density	Bone density will be measured by dual-energy X-ray absorptiometry (DEXA).	Baseline and 6 months
Body mass index (BMI)	BMI Z-score will be assessed by weight (kg) and height (m) that will be combined to report BMI in kg/m^2 Z-score according to the World Health Organization growth curves.	Baseline and 6 months
Food consumption	Food consumption will be assessed by three 24h food records.	Baseline and 6 months
Food insecurity	Food insecurity will be assessed using the Brazilian Food Insecurity Scale (EBIA), a 14-item questionnaire assessing household access to food in the previous 90 days. The total score ranges from 0 to 14, with higher scores indicating greater food insecurity.	Baseline and 6 months
Diet quality (Diet Quality Scale - ESQUADA)	Diet quality will be assessed using the Diet Quality Scale (ESQUADA - Escala de Qualidade da Dieta), a questionnaire based on the Brazilian Dietary Guidelines. The total score ranges from 0 to 100, with higher scores indicating better diet quality.	Baseline and 6 months
Diet quality (Health Eating Index-2020)	Diet quality will also be assessed using the Healthy Eating Index-2020 (HEI-2020), a measure of adherence to the Dietary Guidelines for Americans. The total score ranges from 0 to 100, with higher scores indicating better diet quality.	Baseline and 6 months
Food choice motives	Determinants of food choice will be assessed using the Eating Motivation Survey - Brief Version (TEMS), a questionnaire assessing motivations underlying food choices across multiple domains. Items are rated on a 5-point Likert scale ranging from 1 to 5, with higher scores indicating stronger endorsement of the respective eating motivation.	Baseline and 6 months
Screening for eating disorders	Screening for eating disorders will be conducted using the SCOFF questionnaire, a 5-item screening tool with yes/no responses. Scores range from 0 to 5, with higher scores indicating greater likelihood of an eating disorder. A score of 2 or more positive responses suggests a possible eating disorder and indicates the need for further assessment.	Baseline and 6 months
Eating disorders symptoms	Eating disorder symptoms will be assessed using the Eating Disorder Examination Questionnaire (EDE-Q), a 28-item self-report instrument assessing eating disorder psychopathology over the previous 28 days. Items are rated on a 7-point scale ranging from 0 to 6, with higher scores indicating greater eating disorder psychopathology. The global score ranges from 0 to 6, representing the mean of four subscale scores	Baseline and 6 months
Body image dissatisfaction	Body dissatisfaction will be assessed using the Body Shape Questionnaire (BSQ), a 34-item questionnaire measuring concerns about body shape. Items are rated on a 6-point Likert scale, with total scores ranging from 34 to 204, where higher scores indicate greater body dissatisfaction.	Baseline and 6 months.
Body image appreciation	Body image apprciation will be assessed using the Body Appreciation Scale-2 (BAS-2), a 10-item questionnaire evaluating body appreciation and respect for one's body. Items are rated on a 5-point Likert scale, with total scores ranging from 10 to 50, where higher scores indicate greater body appreciation.	Baseline and 6 months.
Physical activity level and sedentary behavior	Physical activity and sedentary behavior will be assessed using the Physical Activity Questionnaire from the 2015 follow-up of the 1993 Pelotas Birth Cohort, which includes questions on leisure-time physical activity, active transportation, screen time, and sedentary behavior. Outcomes will be reported as time spent in physical activity and sedentary behaviors (minutes per week or hours per day), with higher physical activity indicating healthier behavior and higher sedentary time indicating less favorable behavior.	Baseline and 6 months
Participant's perception of the intervention	Participants' perceptions of the intervention will be assessed through post-intervention semi-structured focus groups. Audio-recorded discussions will be transcribed and analyzed using thematic qualitative analysis to identify key themes related to participants' experiences, perceived benefits, and challenges of the intervention.	6 months

Collaborators and Investigators

• Sponsor: University of Sao Paulo

Study record dates

Study Major Dates

• Study Start (Estimated): March 1, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): December 1, 2026

Study Registration Dates

• First Submitted: March 2, 2026
• First Submitted That Met QC Criteria: March 6, 2026
• First Posted (Actual): March 12, 2026

Study Record Updates

• Last Update Posted (Actual): March 12, 2026
• Last Update Submitted That Met QC Criteria: March 6, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Adolescent; Obesity; Lifestyle; Eating disorders; Transgender; Gender-diverse
• Additional Relevant MeSH Terms: Mental Disorders; Nutrition Disorders; Overnutrition; Body Weight; Signs and Symptoms, Digestive; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Overweight; Obesity; Feeding and Eating Disorders
• Other Study ID Numbers: TRANSCEND study >10 years RCT

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The results produced will be shared as requested by participants. All those who wish to be included will be included in a specific category in publications where this is possible.
• IPD Sharing Time Frame: After the analysis is completed
• IPD Sharing Access Criteria: Having been a participant in the RCT
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF; CSR

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No