This study investigates how weight-loss medications, specifically GLP-1 receptor agonists, affect body composition, with a special focus on preserving muscle mass in adults with obesity. While these medications are highly effective for weight loss, they can sometimes lead to an unwanted loss of valuable muscle mass (a condition that can lead to sarcopenia).
To explore how to prevent this, researchers are conducting a 3- to 6-month randomized controlled trial involving adults aged 30 to 65 years with a BMI greater than 30 kg/m². Participants who are receiving GLP-1 medications will be randomly assigned to one of two groups: one group will receive the standard medication treatment alone, while the other group will receive the medication along with specific dietary guidance focused on increasing daily protein intake.
Adults 30-65 years old
BMI: ≥30 kg/m²
Signed Informed Consent
Uncontrolled type 2 diabetes (HbA1c > 9.0%)
Known cardiovascular disease (e.g., coronary artery disease, heart failure NYHA 3-4)
Chronic kidney disease stage 4-5 (GFR <60 ml/min)
Liver disease (known hepatitis, ALT ≥ 3 or total bilirubin ≥ 2 times ULN)
Parallel
High Protein Dietary Intervention
BehavioralIndividualized dietary guidelines focusing on increased protein consumption to preserve muscle mass during weight loss.
Control (Standard Mediterranean Diet Counseling)
BehavioralStandard nutritional counseling based on the Mediterranean diet pattern as part of usual clinical practice.
Change from Baseline in Muscle Mass
Evaluation of the change in Muscle Mass using a multi-compartment body composition model (4C/5C). This gold-standard approach integrates data from Underwater Weighing (Body Density), Dual-Energy X-ray Absorptiometry (DEXA, for Bone Mineral Content), and Bioelectrical Impedance Spectroscopy (BIS, for Total Body Water) to provide a precise estimation of muscle mass. Results will be reported in kilograms (kg)
Change from Baseline in Body Composition Parameters
Assessment of changes in Fat Mass (FM), Fat-Free Mass (FFM), Total Body Protein (TBPro), Total Body Water (TBW), Intracellular Water (ICW), Extracellular Water (ECW), and hydration of FFM, utilizing the 4- and 5- Compartment models. Assessment of changes in body composition utilizing the 4- and 5-Compartment models. The parameters evaluated include Fat-Free Mass (FFM) and Total Body Protein (TBPro), which will be reported in kilograms (kg). Fat Mass (FM) will be reported both in kilograms (kg) and as a Body Fat Percentage (%). Total Body Water (TBW), Intracellular Water (ICW), and Extracellular Water (ECW) will be reported in liters (L) and as a percentage (%). The hydration of FFM will be reported as a percentage (%).
Change from Baseline in Biochemical and Urinary Markers
Assessment of changes in systemic biomarkers. Blood markers include glycemic control (Fasting Glucose, Insulin \[reported in mg/dL or μU/mL\], HbA1c \[%\]), lipid profile (Total, HDL, LDL Cholesterol, Triglycerides \[mg/dL\]), renal/hepatic function (Creatinine, Urea, Bilirubin \[mg/dL\], ALT \[U/L\]), thyroid function (TSH \[mIU/L\]), inflammatory markers (CRP \[mg/L\]), and micronutrient status (B12, Vit D3, Folic Acid, Calcium, Magnesium \[reported in standard clinical units, e.g., pg/mL, ng/mL, mg/dL\]). Urinary biomarkers (Urinary Urea Nitrogen, Albumin, Creatinine) will also be assessed and reported in standard units (e.g., mg/dL, g/24h).
Long-term Weight Maintenance Efficiency
Evaluation of the sustainability of the intervention results after treatment cessation. This measure primarily tracks the change in Body Weight to assess potential weight regain during the follow-up phase. The preservation of Muscle Mass (MM) and Fat Mass (FM) will also be monitored. Changes in Body Weight, MM, and FM will be reported in kilograms (kg) and as a percentage (%) of the weight/mass lost during the active intervention phase.
Change from Baseline in Sarcopenia Risk
Participants will be classified as "at risk" for early sarcopenia if they meet at least one of the following criteria: 1. SARC-F score ≥4 (on a scale of 0-10) 2. Handgrip strength below the EWGSOP2 thresholds (men \<27 kg, women \<16 kg) Evaluation of sarcopenia risk using a combination of the Greek validated SARC-F questionnaire and handgrip strength measured via a calibrated dynamometer. The SARC-F score ranges from 0 to 10, where higher scores indicate a greater risk of sarcopenia (worse outcome). Handgrip strength will be reported in kilograms (kg). Participants will be classified as "at risk" for early sarcopenia based on the EWGSOP2 criteria if they meet at least one of the following: 1. SARC-F score ≥ 4, or 2. Handgrip strength below the gender-specific thresholds (men \< 27 kg, women \< 16 kg). The overall outcome will be reported as the change in the continuous parameters (SARC-F score and grip strength in kg) and the proportion (%) of participants classified as "at risk".
Click on the lead sponsor to view all of their trials.
Hellenic Mediterranean University
Lead sponsor
University General Hospital of Heraklion
Collaborator
