TBWL (Total Body Weight Loss)
How GLP-1 receptor agonists work — receptors, gastric emptying, and the satiety pathway.
Definition
The percentage of total body weight lost from baseline, reported as the primary endpoint in modern obesity trials. STEP-1 reported −14.9% TBWL on semaglutide 2.4 mg at 68 weeks; SURMOUNT-1 reported −20.9% TBWL on tirzepatide 15 mg at 72 weeks. TBWL is preferred over absolute kg change because it adjusts for starting body weight — a 15% loss in someone starting at 100 kg (15 kg) and 200 kg (30 kg) is clinically equivalent in metabolic terms.
Definition curated by Weight Loss Rankings — sourced from FDA labels and peer-reviewed PubMed literature, never AI-generated summaries.
Related terms in Mechanism
- GLP-1 receptor
- GIP receptor
- Dual agonist
- Gastric emptying
- Food noise
- Triple agonist
- Amylin
- GLP-1 tachyphylaxis
- Non-peptide GLP-1 agonist
- A1C (glycated hemoglobin)
- MASH / MASLD
- C-peptide
- eGFR (estimated glomerular filtration rate)
- Visceral adipose tissue (VAT)
- AHI (apnea-hypopnea index)
- SNAC (oral semaglutide absorption enhancer)
Looking for more depth?
- STEP-1 trial deep-dive
- Browse the full GLP-1 glossary (124 terms across 8 categories)
- Research articles — primary-source deep dives
- Tools and calculators
- Compare GLP-1 telehealth providers